Как правильно написать остеопороз

Osteoporosis
Elderly woman with osteoporosis showing a curved back from compression fractures of her back bones.
Pronunciation	[1][2]
Specialty	Rheumatology, Endocrinology, orthopedics
Symptoms	Increased risk of a broken bone[3]
Complications	Chronic pain[3]
Usual onset	Older age[3]
Risk factors	Alcoholism, anorexia, European or Asian ethnicity, hyperthyroidism, gastrointestinal diseases, surgical removal of the ovaries, kidney disease, smoking, certain medications[3]
Diagnostic method	Dexa Scan( Bone density scan[4])
Treatment	Good diet, exercise, fall prevention, stopping smoking[3]
Medication	Bisphosphonates[5][6]
Frequency	15% (50 year olds), 70% (over 80 year olds)[7]

Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to bone fragility, and consequent increase in fracture risk. It is the most common reason for a broken bone among the elderly.^[3] Bones that commonly break include the vertebrae in the spine, the bones of the forearm, and the hip.^[8] Until a broken bone occurs there are typically no symptoms. Bones may weaken to such a degree that a break may occur with minor stress or spontaneously. After the broken bone heals, the person may have chronic pain and a decreased ability to carry out normal activities.^[3]

Osteoporosis may be due to lower-than-normal maximum bone mass and greater-than-normal bone loss. Bone loss increases after the menopause due to lower levels of estrogen, and after ‘andropause’ due to lower levels of testosterone.^[9][10] Osteoporosis may also occur due to a number of diseases or treatments, including alcoholism, anorexia, hyperthyroidism, kidney disease, and surgical removal of the ovaries. Certain medications increase the rate of bone loss, including some antiseizure medications, chemotherapy, proton pump inhibitors, selective serotonin reuptake inhibitors, and glucocorticosteroids. Smoking, and too little exercise are also risk factors.^[3] Osteoporosis is defined as a bone density of 2.5 standard deviations below that of a young adult. This is typically measured by dual-energy X-ray absorptiometry (DXA or DEXA).^[4]

Prevention of osteoporosis includes a proper diet during childhood, hormone replacement therapy for menopausal women, and efforts to avoid medications that increase the rate of bone loss. Efforts to prevent broken bones in those with osteoporosis include a good diet, exercise, and fall prevention. Lifestyle changes such as stopping smoking and not drinking alcohol may help.^[3] Bisphosphonate medications are useful to decrease future broken bones in those with previous broken bones due to osteoporosis. In those with osteoporosis but no previous broken bones, they are less effective.^{[5][6][needs update][11]} They do not appear to affect the risk of death.^[12]

Osteoporosis becomes more common with age. About 15% of Caucasians in their 50s and 70% of those over 80 are affected.^[7] It is more common in women than men.^[3] In the developed world, depending on the method of diagnosis, 2% to 8% of males and 9% to 38% of females are affected.^[13] Rates of disease in the developing world are unclear.^[14] About 22 million women and 5.5 million men in the European Union had osteoporosis in 2010.^[15] In the United States in 2010, about 8 million women and between 1 and 2 million men had osteoporosis.^[13][16] White and Asian people are at greater risk.^[3] The word «osteoporosis» is from the Greek terms for «porous bones».^[17]

Signs and symptoms[edit]

Osteoporosis itself has no symptoms; its main consequence is the increased risk of bone fractures. Osteoporotic fractures occur in situations where healthy people would not normally break a bone; they are therefore regarded as fragility fractures. Typical fragility fractures occur in the vertebral column, rib, hip and wrist.

Fractures[edit]

Fractures are a common symptom of osteoporosis and can result in disability.^[18] Acute and chronic pain in the elderly is often attributed to fractures from osteoporosis and can lead to further disability and early mortality.^[19] These fractures may also be asymptomatic.^[20] The most common osteoporotic fractures are of the wrist, spine, shoulder and hip. The symptoms of a vertebral collapse («compression fracture») are sudden back pain, often with radicular pain (shooting pain due to nerve root compression) and rarely with spinal cord compression or cauda equina syndrome. Multiple vertebral fractures lead to a stooped posture, loss of height, and chronic pain with resultant reduction in mobility.^[21]

Fractures of the long bones acutely impair mobility and may require surgery. Hip fracture, in particular, usually requires prompt surgery, as serious risks are associated with it, such as deep vein thrombosis and pulmonary embolism. There is also an increased risk of mortality associated with hip surgery, with the mean average mortality rate for Europe being 23.3%, for Asia 17.9%, United States 21% and Australia 24.9%. ^[22]

Fracture risk calculators assess the risk of fracture based upon several criteria, including bone mineral density, age, smoking, alcohol usage, weight, and gender. Recognized calculators include FRAX,^[23] the Garvan FRC calculator and QFracture as well as the open access FREM tool.^[24] The FRAX tool can also be applied in a modification adapted to routinely collected health data.^[25]

The term «established osteoporosis» is used when a broken bone due to osteoporosis has occurred.^[26] Osteoporosis is a part of frailty syndrome.

Risk of falls[edit]

There is an increased risk of falls associated with aging. These falls can lead to skeletal damage at the wrist, spine, hip, knee, foot, and ankle. Part of the fall risk is because of impaired eyesight due to many causes, (e.g. glaucoma, macular degeneration), balance disorder, movement disorders (e.g. Parkinson’s disease), dementia, and sarcopenia (age-related loss of skeletal muscle). Collapse (transient loss of postural tone with or without loss of consciousness). Causes of syncope are manifold, but may include cardiac arrhythmias (irregular heart beat), vasovagal syncope, orthostatic hypotension (abnormal drop in blood pressure on standing up), and seizures. Removal of obstacles and loose carpets in the living environment may substantially reduce falls. Those with previous falls, as well as those with gait or balance disorders, are most at risk.^[27]

Complication[edit]

As well as susceptibility to breaks and fractures, osteoporosis can lead to other complications. Bone fractures which are results from osteoporosis can lead to disability and even an increased chance of death after the injury.^[28]

Depression is considered to a complication of osteoporosis.^[29] People with osteoporosis lose independence and risk being isolated due to less physical activity. This will further hinder the ability to manage health issues.^[29]

Osteoporosis is also linked to respiratory and cardiovascular health issues, such as loss of lung capacity. Multiple fractures lead to a collapsed thoracic spine, which makes less air being able to move into the lungs. Every thoracic vertebral body collapsed results in the loss of nearly 10% of lung volume.^[30]

Risk factors[edit]

Risk factors for osteoporotic fracture can be split between nonmodifiable and (potentially) modifiable. In addition, osteoporosis is a recognized complication of specific diseases and disorders. Medication use is theoretically modifiable, although in many cases, the use of medication that increases osteoporosis risk may be unavoidable.
Caffeine is not a risk factor for osteoporosis.^[31]

Nonmodifiable[edit]

• The most important risk factors for osteoporosis are advanced age (in both men and women) and female sex; estrogen deficiency following menopause or surgical removal of the ovaries is correlated with a rapid reduction in bone mineral density, while in men, a decrease in testosterone levels has a comparable (but less pronounced) effect.^[33][34]
• Ethnicity: While osteoporosis occurs in people from all ethnic groups, European or Asian ancestry predisposes for osteoporosis.^[35]
• Heredity: Those with a family history of fracture or osteoporosis are at an increased risk; the heritability of the fracture, as well as low bone mineral density, is relatively high, ranging from 25 to 80%. At least 30 genes are associated with the development of osteoporosis.^[36]
• Those who have already had a fracture are at least twice as likely to have another fracture compared to someone of the same age and sex.^[37]
• Build: A small stature is also a nonmodifiable risk factor associated with the development of osteoporosis.^[38]

Potentially modifiable[edit]

• Excessive alcohol: Although small amounts of alcohol might be beneficial (bone density increases with increasing alcohol intake, although the link has not been conclusively shown as causal), chronic heavy drinking (alcohol intake greater than three units/day) probably increases fracture risk despite any beneficial effects on bone density.^[39][40]
• Vitamin D deficiency:^[41][42] Low circulating Vitamin D is common among the elderly worldwide.^[4] Mild vitamin D insufficiency is associated with increased parathyroid hormone (PTH) production.^[4] PTH increases bone resorption, leading to bone loss. A positive association exists between serum 1,25-dihydroxycholecalciferol levels and bone mineral density, while PTH is negatively associated with bone mineral density.^[4]
• Tobacco smoking: Many studies have associated smoking with decreased bone health, but the mechanisms are unclear.^[43][44][45] Tobacco smoking has been proposed to inhibit the activity of osteoblasts, and is an independent risk factor for osteoporosis.^[39][46] Smoking also results in increased breakdown of exogenous estrogen, lower body weight and earlier menopause, all of which contribute to lower bone mineral density.^[4]
• Malnutrition: Nutrition has an important and complex role in maintenance of good bone. Identified risk factors include low dietary calcium and/or phosphorus, magnesium, zinc, boron, iron, fluoride, copper, vitamins A, K, E and C (and D where skin exposure to sunlight provides an inadequate supply). Excess sodium is a risk factor. High blood acidity may be diet-related, and is a known antagonist of bone.^[47] Some have identified low protein intake as associated with lower peak bone mass during adolescence and lower bone mineral density in elderly populations.^[4] Conversely, some have identified low protein intake as a positive factor, protein is among the causes of dietary acidity. Imbalance of omega-6 to omega-3 polyunsaturated fats is yet another identified risk factor.^[48]
• A diet high in protein may be optimal for bone health, as higher protein diets tend to increase absorption of calcium from the diet and are associated with higher bone density.^[49][50] No interventional trials have been performed on dietary protein in the prevention and treatment of osteoporosis ^[51] A meta-analysis of published medical studies shows that higher protein diet helps slightly with lower spine density but does not show significant improvement with other bones.^[52]
• Underweight/inactive: Bone remodeling occurs in response to physical stress, so physical inactivity can lead to significant bone loss.^[4] Weight bearing exercise can increase peak bone mass achieved in adolescence,^[4] and a highly significant correlation between bone strength and muscle strength has been determined.^[53] The incidence of osteoporosis is lower in overweight people.^[54]
• Endurance training: In female endurance athletes, large volumes of training can lead to decreased bone density and an increased risk of osteoporosis.^[55] This effect might be caused by intense training suppressing menstruation, producing amenorrhea, and it is part of the female athlete triad.^[56] However, for male athletes, the situation is less clear, and although some studies have reported low bone density in elite male endurance athletes,^[57] others have instead seen increased leg bone density.^[58][59]
• Heavy metals: A strong association between cadmium and lead with bone disease has been established. Low-level exposure to cadmium is associated with an increased loss of bone mineral density readily in both genders, leading to pain and increased risk of fractures, especially in the elderly and in females. Higher cadmium exposure results in osteomalacia (softening of the bone).^[60]
• Soft drinks: Some studies indicate soft drinks (many of which contain phosphoric acid) may increase risk of osteoporosis, at least in women.^[61] Others suggest soft drinks may displace calcium-containing drinks from the diet rather than directly causing osteoporosis.^[62]
• Proton pump inhibitors (such as lansoprazole, esomeprazole, and omeprazole), which decrease the production of stomach acid, are a risk factor for bone fractures if taken for two or more years, due to decreased absorption of calcium in the stomach.^[63]

Medical disorders[edit]

Many diseases and disorders have been associated with osteoporosis.^[64] For some, the underlying mechanism influencing the bone metabolism is straightforward, whereas for others the causes are multiple or unknown.

• In general, immobilization causes bone loss (following the ‘use it or lose it’ rule). For example, localized osteoporosis can occur after prolonged immobilization of a fractured limb in a cast. This is also more common in active people with a high bone turn-over (for example, athletes). Other examples include bone loss during space flight or in people who are bedridden or use wheelchairs for various reasons.^{[citation needed]}
• Hypogonadal states can cause secondary osteoporosis. These include Turner syndrome, Klinefelter syndrome, Kallmann syndrome, anorexia nervosa, andropause,^[65] hypothalamic amenorrhea or hyperprolactinemia.^[65] In females, the effect of hypogonadism is mediated by estrogen deficiency. It can appear as early menopause (<45 years) or from prolonged premenopausal amenorrhea (>1 year). Bilateral oophorectomy (surgical removal of the ovaries) and premature ovarian failure cause deficient estrogen production. In males, testosterone deficiency is the cause (for example, andropause or after surgical removal of the testes).
• Endocrine disorders that can induce bone loss include Cushing’s syndrome,^[4] hyperparathyroidism,^[4] hyperthyroidism,^[4] hypothyroidism, diabetes mellitus type 1 and 2,^[66] acromegaly, and adrenal insufficiency.^[64]
• Malnutrition, parenteral nutrition^[4] and malabsorption can lead to osteoporosis. Nutritional and gastrointestinal disorders that can predispose to osteoporosis include undiagnosed and untreated coeliac disease (both symptomatic and asymptomatic people),^[4][67] Crohn’s disease,^[68] ulcerative colitis,^[68] cystic fibrosis,^[68] surgery^[65] (after gastrectomy, intestinal bypass surgery or bowel resection) and severe liver disease (especially primary biliary cirrhosis).^[65] People with lactose intolerance or milk allergy may develop osteoporosis due to restrictions of calcium-containing foods.^[69] Individuals with bulimia can also develop osteoporosis. Those with an otherwise adequate calcium intake can develop osteoporosis due to the inability to absorb calcium and/or vitamin D. Other micronutrients such as vitamin K or vitamin B₁₂ deficiency may also contribute.
• People with rheumatologic disorders such as rheumatoid arthritis,^[65] ankylosing spondylitis,^[65] systemic lupus erythematosus and polyarticular juvenile idiopathic arthritis are at increased risk of osteoporosis, either as part of their disease or because of other risk factors (notably corticosteroid therapy). Systemic diseases such as amyloidosis and sarcoidosis can also lead to osteoporosis.
• Chronic kidney disease can lead to renal osteodystrophy.^[70]
• Hematologic disorders linked to osteoporosis are multiple myeloma^[65] and other monoclonal gammopathies,^[66] lymphoma, leukemia, mastocytosis,^[65] hemophilia, sickle-cell disease and thalassemia.
• Several inherited or genetic disorders have been linked to osteoporosis. These include osteogenesis imperfecta,^[65] Multicentric carpotarsal osteolysis syndrome,^[71] Multicentric Osteolysis, Nodulosis, and Arthropathy,^[72] Marfan syndrome,^[65] hemochromatosis,^[4] hypophosphatasia^[73] (for which it is often misdiagnosed),^[74] glycogen storage diseases, homocystinuria,^[65] Ehlers–Danlos syndrome,^[65] porphyria, Menkes’ syndrome, epidermolysis bullosa and Gaucher’s disease.
• People with scoliosis of unknown cause also have a higher risk of osteoporosis. Bone loss can be a feature of complex regional pain syndrome. It is also more frequent in people with Parkinson’s disease and chronic obstructive pulmonary disease.
• People with Parkinson’s disease have a higher risk of broken bones. This is related to poor balance and poor bone density.^[75] In Parkinson’s disease there may be a link between the loss of dopaminergic neurons and altered calcium metabolism^[76] (and iron metabolism) causing a stiffening of the skeleton and kyphosis.

Medication[edit]

Certain medications have been associated with an increase in osteoporosis risk; only glucocorticosteroids and anticonvulsants are classically associated, but evidence is emerging with regard to other drugs.

• Steroid-induced osteoporosis (SIOP) arises due to use of glucocorticoids – analogous to Cushing’s syndrome and involving mainly the axial skeleton. The synthetic glucocorticoid prescription drug prednisone is a main candidate after prolonged intake. Some professional guidelines recommend prophylaxis in patients who take the equivalent of more than 30 mg hydrocortisone (7.5 mg of prednisolone), especially when this is in excess of three months.^[77] It is recommended to use calcium or Vitamin D as prevention.^[78] Alternate day use may not prevent this complication.^[79]
• Barbiturates, phenytoin and some other enzyme-inducing antiepileptics – these probably accelerate the metabolism of vitamin D.^[80]
• L-Thyroxine over-replacement may contribute to osteoporosis, in a similar fashion as thyrotoxicosis does.^[64] This can be relevant in subclinical hypothyroidism.
• Several drugs induce hypogonadism, for example aromatase inhibitors used in breast cancer, methotrexate and other antimetabolite drugs, depot progesterone and gonadotropin-releasing hormone agonists.
• Anticoagulants – long-term use of heparin is associated with a decrease in bone density,^[81] and warfarin (and related coumarins) have been linked with an increased risk in osteoporotic fracture in long-term use.^[82]
• Proton pump inhibitors – these drugs inhibit the production of stomach acid; this is thought to interfere with calcium absorption.^[83] Chronic phosphate binding may also occur with aluminium-containing antacids.^[64]
• Thiazolidinediones (used for diabetes) – rosiglitazone and possibly pioglitazone, inhibitors of PPARγ, have been linked with an increased risk of osteoporosis and fracture.^[84]
• Chronic lithium therapy has been associated with osteoporosis.^[64]

Evolutionary[edit]

Age-related bone loss is common among humans due to exhibiting less dense bones than other primate species.^[85] Because of the more porous bones of humans, frequency of severe osteoporosis and osteoporosis related fractures is higher.^[86] The human vulnerability to osteoporosis is an obvious cost but it can be justified by the advantage of bipedalism inferring that this vulnerability is the byproduct of such.^[86] It has been suggested that porous bones help to absorb the increased stress that we have on two surfaces compared to our primate counterparts who have four surfaces to disperse the force.^[85] In addition, the porosity allows for more flexibility and a lighter skeleton that is easier to support.^[86] One other consideration may be that diets today have much lower amounts of calcium than the diets of other primates or the tetrapedal ancestors to humans which may lead to higher likelihood to show signs of osteoporosis.^[87]

Fracture risk assessment[edit]

In the absence of risk factors other than sex and age a BMD measurement using dual-energy X-ray absorptiometry (DXA) is recommended for women at age 65. For women with risk factors a clinical FRAX is advised at age 50.

Pathogenesis[edit]

The underlying mechanism in all cases of osteoporosis is an imbalance between bone resorption and bone formation.^[88][89] In normal bone, matrix remodeling of bone is constant; up to 10% of all bone mass may be undergoing remodeling at any point in time. The process takes place in bone multicellular units (BMUs) as first described by Frost & Thomas in 1963.^[90] Osteoclasts are assisted by transcription factor PU.1 to degrade the bone matrix, while osteoblasts rebuild the bone matrix. Low bone mass density can then occur when osteoclasts are degrading the bone matrix faster than the osteoblasts are rebuilding the bone.^[88][91]

The three main mechanisms by which osteoporosis develops are an inadequate peak bone mass (the skeleton develops insufficient mass and strength during growth), excessive bone resorption, and inadequate formation of new bone during remodeling, likely due to mesenchymal stem cells biasing away from the osteoblast and toward the marrow adipocyte lineage.^[92] An interplay of these three mechanisms underlies the development of fragile bone tissue.^[36] Hormonal factors strongly determine the rate of bone resorption; lack of estrogen (e.g. as a result of menopause) increases bone resorption, as well as decreasing the deposition of new bone that normally takes place in weight-bearing bones. The amount of estrogen needed to suppress this process is lower than that normally needed to stimulate the uterus and breast gland. The α-form of the estrogen receptor appears to be the most important in regulating bone turnover.^[36] In addition to estrogen, calcium metabolism plays a significant role in bone turnover, and deficiency of calcium and vitamin D leads to impaired bone deposition; in addition, the parathyroid glands react to low calcium levels by secreting parathyroid hormone (parathormone, PTH), which increases bone resorption to ensure sufficient calcium in the blood. The role of calcitonin, a hormone generated by the thyroid that increases bone deposition, is less clear and probably not as significant as that of PTH.^[36]

The activation of osteoclasts is regulated by various molecular signals, of which RANKL (receptor activator of nuclear factor kappa-B ligand) is one of the best-studied.^[89] This molecule is produced by osteoblasts and other cells (e.g. lymphocytes), and stimulates RANK (receptor activator of nuclear factor κB). Osteoprotegerin (OPG) binds RANKL before it has an opportunity to bind to RANK, and hence suppresses its ability to increase bone resorption. RANKL, RANK, and OPG are closely related to tumor necrosis factor and its receptors. The role of the Wnt signaling pathway is recognized, but less well understood. Local production of eicosanoids and interleukins is thought to participate in the regulation of bone turnover, and excess or reduced production of these mediators may underlie the development of osteoporosis.^[36] Osteoclast maturation and activity is also regulated by activation of colony stimulating factor 1 receptor (CSF1R).^[93] Menopause-associated increase production of TNF-α stimulates stromal cells to produce colony stimulating factor 1 (CSF-1) which activates CSF1R and stimulates osteoclasts to reabsorb bone.^[94]

Trabecular bone (or cancellous bone) is the sponge-like bone in the ends of long bones and vertebrae. Cortical bone is the hard outer shell of bones and the middle of long bones. Because osteoblasts and osteoclasts inhabit the surface of bones, trabecular bone is more active and is more subject to bone turnover and remodeling. Not only is bone density decreased, but the microarchitecture of bone is also disrupted. The weaker spicules of trabecular bone break («microcracks»), and are replaced by weaker bone. Common osteoporotic fracture sites, the wrist, the hip, and the spine, have a relatively high trabecular bone to cortical bone ratio. These areas rely on the trabecular bone for strength, so the intense remodeling causes these areas to degenerate most when the remodeling is imbalanced.^{[citation needed]} Around the ages of 30–35, cancellous or trabecular bone loss begins. Women may lose as much as 50%, while men lose about 30%.^[38]

• 

  Light micrograph of an osteoclast displaying typical distinguishing characteristics: a large cell with multiple nuclei and a «foamy» cytosol.

• 

  Collapse of vertebra on the right, normal on the left

Diagnosis[edit]

Osteoporosis can be diagnosed using conventional radiography and by measuring the bone mineral density (BMD).^[95] The most popular method of measuring BMD is dual-energy X-ray absorptiometry.^{[citation needed]}

In addition to the detection of abnormal BMD, the diagnosis of osteoporosis requires investigations into potentially modifiable underlying causes; this may be done with blood tests. Depending on the likelihood of an underlying problem, investigations for cancer with metastasis to the bone, multiple myeloma, Cushing’s disease and other above-mentioned causes may be performed.^{[citation needed]}

Conventional radiography[edit]

Conventional radiography is useful, both by itself and in conjunction with CT or MRI, for detecting complications of osteopenia (reduced bone mass; pre-osteoporosis), such as fractures; for differential diagnosis of osteopenia; or for follow-up examinations in specific clinical settings, such as soft tissue calcifications, secondary hyperparathyroidism, or osteomalacia in renal osteodystrophy. However, radiography is relatively insensitive to detection of early disease and requires a substantial amount of bone loss (about 30%) to be apparent on X-ray images.^[96][97]

The main radiographic features of generalized osteoporosis are cortical thinning and increased radiolucency. Frequent complications of osteoporosis are vertebral fractures for which spinal radiography can help considerably in diagnosis and follow-up. Vertebral height measurements can objectively be made using plain-film X-rays by using several methods such as height loss together with area reduction, particularly when looking at vertical deformity in T4-L4, or by determining a spinal fracture index that takes into account the number of vertebrae involved. Involvement of multiple vertebral bodies leads to kyphosis of the thoracic spine, leading to what is known as dowager’s hump.^[98][99]

Dual-energy X-ray[edit]

Dual-energy X-ray absorptiometry (DEXA scan) is considered the gold standard for the diagnosis of osteoporosis. Osteoporosis is diagnosed when the bone mineral density is less than or equal to 2.5 standard deviations below that of a young (30–40-year-old^[4]:58), healthy adult women reference population. This is translated as a T-score. But because bone density decreases with age, more people become osteoporotic with increasing age.^[4]:58 The World Health Organization has established the following diagnostic guidelines:^[4][26]

Category	T-score range	% young women
Normal	T-score ≥ −1.0	85%
Osteopenia	−2.5 < T-score < −1.0	14%
Osteoporosis	T-score ≤ −2.5	0.6%
Severe osteoporosis	T-score ≤ −2.5 with fragility fracture[26]

The International Society for Clinical Densitometry takes the position that a diagnosis of osteoporosis in men under 50 years of age should not be made on the basis of densitometric criteria alone. It also states, for premenopausal women, Z-scores (comparison with age group rather than peak bone mass) rather than T-scores should be used, and the diagnosis of osteoporosis in such women also should not be made on the basis of densitometric criteria alone.^[100]

Biomarkers[edit]

Chemical biomarkers are a useful tool in detecting bone degradation. The enzyme cathepsin K breaks down type-I collagen, an important constituent in bones. Prepared antibodies can recognize the resulting fragment, called a neoepitope, as a way to diagnose osteoporosis.^[101] Increased urinary excretion of C-telopeptides, a type-I collagen breakdown product, also serves as a biomarker for osteoporosis.^[102]

Comparison of bone pathology

view talk edit Condition	Calcium	Phosphate	Alkaline phosphatase	Parathyroid hormone	Comments
Osteopenia	unaffected	unaffected	normal	unaffected	decreased bone mass
Osteopetrosis	unaffected	unaffected	elevated	unaffected[citation needed]	thick dense bones also known as marble bone
Osteomalacia and rickets	decreased	decreased	elevated	elevated	soft bones
Osteitis fibrosa cystica	elevated	decreased	elevated	elevated	brown tumors
Paget’s disease of bone	unaffected	unaffected	variable (depending on stage of disease)	unaffected	abnormal bone architecture

Other measuring tools[edit]

Quantitative computed tomography (QCT) differs from DXA in that it gives separate estimates of BMD for trabecular and cortical bone and reports precise volumetric mineral density in mg/cm³ rather than BMD’s relative Z-score. Among QCT’s advantages: it can be performed at axial and peripheral sites, can be calculated from existing CT scans without a separate radiation dose, is sensitive to change over time, can analyze a region of any size or shape, excludes irrelevant tissue such as fat, muscle, and air, and does not require knowledge of the patient’s subpopulation in order to create a clinical score (e.g. the Z-score of all females of a certain age). Among QCT’s disadvantages: it requires a high radiation dose compared to DXA, CT scanners are large and expensive, and because its practice has been less standardized than BMD, its results are more operator-dependent. Peripheral QCT has been introduced to improve upon the limitations of DXA and QCT.^[95]

Quantitative ultrasound has many advantages in assessing osteoporosis. The modality is small, no ionizing radiation is involved, measurements can be made quickly and easily, and the cost of the device is low compared with DXA and QCT devices. The calcaneus is the most common skeletal site for quantitative ultrasound assessment because it has a high percentage of trabecular bone that is replaced more often than cortical bone, providing early evidence of metabolic change. Also, the calcaneus is fairly flat and parallel, reducing repositioning errors. The method can be applied to children, neonates, and preterm infants, just as well as to adults.^[95] Some ultrasound devices can be used on the tibia.^[103]

Screening[edit]

The U.S. Preventive Services Task Force (USPSTF) recommend that all women 65 years of age or older be screened by bone densitometry.^[104] Additionally they recommend screening younger women with risk factors.^[104] There is insufficient evidence to make recommendations about the intervals for repeated screening and the appropriate age to stop screening.^[105]

In men the harm versus benefit of screening for osteoporosis is unknown.^[104] Prescrire states that the need to test for osteoporosis in those who have not had a previous bone fracture is unclear.^[106] The International Society for Clinical Densitometry suggest BMD testing for men 70 or older, or those who are indicated for risk equal to that of a 70‑year‑old.^[107] A number of tools exist to help determine who is reasonable to test.^[108]

Prevention[edit]

Lifestyle prevention of osteoporosis is in many aspects the inverse of the potentially modifiable risk factors.^[109] As tobacco smoking and high alcohol intake have been linked with osteoporosis, smoking cessation and moderation of alcohol intake are commonly recommended as ways to help prevent it.^[110]

In people with coeliac disease adherence to a gluten-free diet decreases the risk of developing osteoporosis^[111] and increases bone density.^[67] The diet must ensure optimal calcium intake (of at least one gram daily) and measuring vitamin D levels is recommended, and to take specific supplements if necessary.^[111]

Nutrition[edit]

Studies of the benefits of supplementation with calcium and vitamin D are conflicting, possibly because most studies did not have people with low dietary intakes.^[112] A 2018 review by the USPSTF found low-quality evidence that the routine use of calcium and vitamin D supplements (or both supplements together) did not reduce the risk of having an osteoporotic fracture in male and female adults living in the community who had no known history of vitamin D deficiency, osteoporosis, or a fracture.^[113] The USPSTF does not recommend low dose supplementation (less than 1 g of calcium and 400 IU of vitamin D) in postmenopausal women as there does not appear to be a difference in fracture risk.^[114] A 2015 review found little data that supplementation of calcium decreases the risk of fractures.^[115] While some meta-analyses have found a benefit of vitamin D supplements combined with calcium for fractures, they did not find a benefit of vitamin D supplements (800 IU/day or less) alone.^[116][117] While supplementation does not appear to affect the risk of death,^[113][117] an increased risk of myocardial infarctions ^[118][119] kidney stones,^[113] and stomach problems^[117] is associated with calcium supplementation.

Vitamin K deficiency is also a risk factor for osteoporotic fractures.^[120] The gene gamma-glutamyl carboxylase (GGCX) is dependent on vitamin K. Functional polymorphisms in the gene could attribute to variation in bone metabolism and BMD. ^[121] Vitamin K2 is also used as a means of treatment for osteoporosis and the polymorphisms of GGCX could explain the individual variation in the response to treatment of vitamin K.^[122]

Dietary sources of calcium include dairy products, leafy greens, legumes, and beans.^[123] There has been conflicting evidence about whether or not dairy is an adequate source of calcium to prevent fractures. The National Academy of Sciences recommends 1,000 mg of calcium for those aged 19–50, and 1,200 mg for those aged 50 and above.^[124] A review of the evidence shows no adverse effect of higher protein intake on bone health.^[125]

Physical exercise[edit]

There is limited evidence indicating that exercise is helpful in promoting bone health.^[126] There is some evidence that physical exercise may be beneficial for bone density in postmenopausal women and lead to a slightly reduced risk of a bone fracture (absolute difference 4%).^[127] Weight bearing exercise has been found to cause an adaptive response in the skeleton.^[128] Weight bearing exercise promotes osteoblast activity, protecting bone density.^[129] A position statement concluded that increased bone activity and weight-bearing exercises at a young age prevent bone fragility in adults.^[130] Bicycling and swimming are not considered weight-bearing exercise. Neither contribute to slowing bone loss with age, and professional bicycle racing has a negative effect on bone density.^[131]

Low-quality evidence suggests that exercise may reduce pain and improve quality of life of people with vertebral fractures and there is moderate-quality evidence that exercise will likely improve physical performance in individuals with vertebral fractures.^[132]

Physical therapy[edit]

People with osteoporosis are at higher risk of falls due to poor postural control, muscle weakness, and overall deconditioning.^[133] Postural control is important to maintaining functional movements such as walking and standing. Physical therapy may be an effective way to address postural weakness that may result from vertebral fractures, which are common in people with osteoporosis. Physical therapy treatment plans for people with vertebral fractures include balance training, postural correction, trunk and lower extremity muscle strengthening exercises, and moderate-intensity aerobic physical activity.^[132] The goal of these interventions are to regain normal spine curvatures, increase spine stability, and improve functional performance.^[132] Physical therapy interventions were also designed to slow the rate of bone loss through home exercise programs.^[133]

Whole body vibration therapy has also been suggested as a physical therapy intervention. Moderate to low-quality evidence indicates that whole body vibration therapy may reduce the risk of falls.^[134] There are conflicting reviews as to whether vibration therapy improves bone mineral density.^[134][135]

Physical therapy can aid in overall prevention in the development of osteoporosis through therapeutic exercise. Prescribed amounts of mechanical loading or increased forces on the bones promote bone formation and vascularization in various ways, therefore offering a preventative measure that is not reliant on drugs. Specific exercise interacts with the body’s hormones and signaling pathways which encourages the maintenance of a healthy skeleton.^[136]

Hormone therapy[edit]

Reduced oestrogen levels increase the risk of osteoporosis, so hormone replacement therapy when women reach the menopause may reduce the incidence of osteoporosis.

Management[edit]

Lifestyle[edit]

Weight-bearing endurance exercise and/or exercises to strengthen muscles improve bone strength in those with osteoporosis.^[127][137] Aerobics, weight bearing, and resistance exercises all maintain or increase BMD in postmenopausal women.^[127] Fall prevention can help prevent osteoporosis complications. There is some evidence for hip protectors specifically among those who are in care homes.^[138]

Pharmacologic therapy[edit]

The US National Osteoporosis Foundation recommends pharmacologic treatment for patients with hip of spine fracture thought to be related to osteoporosis, those with BMD 2.5 SD or more below the young normal mean (T-score -2.5 or below), and those with BMD between 1 and 2.5 SD below normal mean whose 10-year risk, using FRAX, for hip fracture is equal or more than 3%.^[139]
Bisphosphonates are useful in decreasing the risk of future fractures in those who have already sustained a fracture due to osteoporosis.^{[5][6][110][140]} This benefit is present when taken for three to four years.^[141][142] They do not appear to change the overall risk of death.^[12] Tentative evidence does not support the use of bisphosphonates as a standard treatment for secondary osteoporosis in children.^[142] Different bisphosphonates have not been directly compared, therefore it is unknown if one is better than another.^[110] Fracture risk reduction is between 25 and 70% depending on the bone involved.^[110] There are concerns of atypical femoral fractures and osteonecrosis of the jaw with long-term use, but these risks are low.^[110][143] With evidence of little benefit when used for more than three to five years and in light of the potential adverse events, it may be appropriate to stop treatment after this time.^[141] One medical organization recommends that after five years of medications by mouth or three years of intravenous medication among those at low risk, bisphosphonate treatment can be stopped.^[144][145] In those at higher risk they recommend up to ten years of medication by mouth or six years of intravenous treatment.^[144]

The goal of osteoporosis management is to prevent osteoporotic fractures, but for those who have sustained one already it is more urgent to prevent a secondary fracture.^[146] That is because patients with a fracture are more likely to experience a recurrent fracture, with marker increase in morbidity and mortality compared.^[146] Among the five bisphosphonates, no significant differences were found for a secondary fracture for all fracture endpoints combined.^[146] That being said, alendronate was identified as the most efficacious for secondary prevention of vertebral and hip fractures while zoledronate showed better performance for nonvertebral non-hip fracture prevention.^[146] There is concern that many people do not receive appropriate pharmacological therapy after a low-impact fracture.^[147]

For those with osteoporosis but who have not had a fracture, evidence does not support a reduction in fracture risk with risedronate^[6] or etidronate.^[11] Alendronate decreases fractures of the spine but does not have any effect on other types of fractures.^[5] Half stop their medications within a year.^[148] When on treatment with bisphosphonates rechecking bone mineral density is not needed.^[145] There is tentative evidence of benefit in males with osteoporosis.^[149]

Fluoride supplementation does not appear to be effective in postmenopausal osteoporosis, as even though it increases bone density, it does not decrease the risk of fractures.^[150][151]

Teriparatide (a recombinant parathyroid hormone) has been shown to be effective in treatment of women with postmenopausal osteoporosis.^[152][140] Some evidence also indicates strontium ranelate is effective in decreasing the risk of vertebral and nonvertebral fractures in postmenopausal women with osteoporosis.^[153] Hormone replacement therapy, while effective for osteoporosis, is only recommended in women who also have menopausal symptoms.^[110] It is not recommended for osteoporosis by itself.^[145] Raloxifene, while effective in decreasing vertebral fractures, does not affect the risk of nonvertebral fracture.^[110] And while it reduces the risk of breast cancer, it increases the risk of blood clots and strokes.^[110] While denosumab is effective at preventing fractures in women,^[110] there is not clear evidence of benefit in males.^[149] In hypogonadal men, testosterone has been shown to improve bone quantity and quality, but, as of 2008, no studies evaluated its effect on fracture risk or in men with a normal testosterone levels.^[66] Calcitonin while once recommended is no longer due to the associated risk of cancer and questionable effect on fracture risk.^[154] Alendronic acid/colecalciferol can be taken to treat this condition in post-menopausal women.^[155]

Romosozumab (sold under the brand name Evenity) is a monoclonal antibody against sclerostin. Romosozumab is usually reserved for patients with very high fracture risk and is the only available drug therapy for osteoporosis that leads to simultaneous inhibition of bone resorption together with an anabolic effect.^[156][157]

Certain medications like alendronate, etidronate, risedronate, raloxifene, and strontium ranelate can help to prevent osteoporotic fragility fractures in postmenopausal women with osteoporosis.^[158] Tentative evidence suggests that Chinese herbal medicines may have potential benefits on bone mineral density.^[159]

Prognosis[edit]

Hip fractures per 1000 person-years^[160]

WHO category	Age 50–64	Age > 64	Overall
Normal	5.3	9.4	6.6
Osteopenia	11.4	19.6	15.7
Osteoporosis	22.4	46.6	40.6

Although people with osteoporosis have increased mortality due to the complications of fracture, the fracture itself is rarely lethal.

Hip fractures can lead to decreased mobility and additional risks of numerous complications (such as deep venous thrombosis and/or pulmonary embolism, and pneumonia). The six-month mortality rate for those aged 50 and above following hip fracture was found to be around 13.5%, with a substantial proportion (almost 13%) needing total assistance to mobilize after a hip fracture.^[161]

Vertebral fractures, while having a smaller impact on mortality, can lead to severe chronic pain of neurogenic origin, which can be hard to control, as well as deformity. Though rare, multiple vertebral fractures can lead to such severe hunchback (kyphosis), the resulting pressure on internal organs can impair one’s ability to breathe.

Apart from risk of death and other complications, osteoporotic fractures are associated with a reduced health-related quality of life.^[162]

The condition is responsible for millions of fractures annually, mostly involving the lumbar vertebrae, hip, and wrist. Fragility fractures of ribs are also common in men.

Fractures[edit]

Hip fractures are responsible for the most serious consequences of osteoporosis. In the United States, more than 250,000 hip fractures annually are attributable to osteoporosis.^[163] A 50-year-old white woman is estimated to have a 17.5% lifetime risk of fracture of the proximal femur. The incidence of hip fractures increases each decade from the sixth through the ninth for both women and men for all populations. The highest incidence is found among men and women ages 80 or older.^[164]

Between 35 and 50% of all women over 50 had at least one vertebral fracture. In the United States, 700,000 vertebral fractures occur annually, but only about a third are recognized. In a series of 9704 women aged 68.8 on average studied for 15 years, 324 had already sustained a vertebral fracture at entry into the study and 18.2% developed a vertebral fracture, but that risk rose to 41.4% in women who had a previous vertebral fracture.^[165]

In the United States, 250,000 wrist fractures annually are attributable to osteoporosis.^[163] Wrist fractures are the third most common type of osteoporotic fractures. The lifetime risk of sustaining a Colles’ fracture is about 16% for white women. By the time women reach age 70, about 20% have had at least one wrist fracture.^[164]

Fragility fractures of the ribs are common in men as young as age 35.^{[citation needed]} These are often overlooked as signs of osteoporosis, as these men are often physically active and develop the fracture in the course of physical activity, such as falling while water skiing or jet skiing.

Epidemiology[edit]

This article needs to be updated. Please help update this article to reflect recent events or newly available information. (December 2020)

It is estimated that 200 million people have osteoporosis.^[167] Osteoporosis becomes more common with age.^[3] About 15% of Caucasians in their 50s and 70% of those over 80 are affected.^[7] It is more common in women than men.^[3] In the developed world, depending on the method of diagnosis, 2% to 8% of males and 9% to 38% of females are affected.^[13] Rates of disease in the developing world are unclear.^[14]

Postmenopausal women have a higher rate of osteoporosis and fractures than older men.^[168] Postmenopausal women have decreased estrogen which contributes to their higher rates of osteoporosis.^[168] A 60-year-old woman has a 44% risk of fracture while a 60-year-old man has a 25% risk of fracture.^[168]

There are 8.9 million fractures worldwide per year due to osteoporosis.^[169] Globally, 1 in 3 women and 1 in 5 men over the age of 50 will have an osteoporotic fracture.^[169] Data from the United States shows a decrease in osteoporosis within the general population and in white women, from 18% in 1994 to 10% in 2006.^[170] White and Asian people are at greater risk.^[3] People of African descent are at a decreased risk of fractures due to osteoporosis, although they have the highest risk of death following an osteoporotic fracture.^[170]

It has been shown that latitude affects risk of osteoporotic fracture.^[166] Areas of higher latitude such as Northern Europe receive less Vitamin D through sunlight compared to regions closer to the equator, and consequently have higher fracture rates in comparison to lower latitudes.^[166] For example, Swedish men and women have a 13% and 28.5% risk of hip fracture by age 50, respectively, whereas this risk is only 1.9% and 2.4% in Chinese men and women.^[170] Diet may also be a factor that is responsible for this difference, as vitamin D, calcium, magnesium, and folate are all linked to bone mineral density.^[171]

There is also an association between Celiac Disease and increased risk of osteoporosis.^[172] In studies with premenopausal females and males, there was a correlation between Celiac Disease and osteoporosis and osteopenia.^[172] Celiac Disease can decrease absorption of nutrients in the small intestine such as calcium, and a gluten-free diet can help people with Celiac Disease to revert to normal absorption in the gut.^[173]

About 22 million women and 5.5 million men in the European Union had osteoporosis in 2010.^[15] In the United States in 2010 about 8 million women and one to 2 million men had osteoporosis.^[13][16] This places a large economic burden on the healthcare system due to costs of treatment, long-term disability, and loss of productivity in the working population. The EU spends 37 billion euros per year in healthcare costs related to osteoporosis, and the US spends an estimated US$19 billion annually for related healthcare costs.^[169]

History[edit]

The link between age-related reductions in bone density goes back to the early 1800s. French pathologist Jean Lobstein coined the term osteoporosis.^[17] The American endocrinologist Fuller Albright linked osteoporosis with the postmenopausal state.^[174]

Anthropologists have studied skeletal remains that showed loss of bone density and associated structural changes that were linked to a chronic malnutrition in the agricultural area in which these individuals lived. «It follows that the skeletal deformation may be attributed to their heavy labor in agriculture as well as to their chronic malnutrition», causing the osteoporosis seen when radiographs of the remains were made.^[175]

See also[edit]

• Spaceflight osteopenia
• World Osteoporosis Day

References[edit]

External links[edit]

• Handout on Health: Osteoporosis  – US National Institute of Arthritis and Musculoskeletal and Skin Diseases
• Osteoporosis  – l NIH Osteoporosis and Related Bone Diseases – National Resource Center
• Office of the Surgeon General (2004). Bone Health and Osteoporosis: A Report of the Surgeon General. Rockville, MD: U.S. Department of Health and Human Services. PMID 20945569. Retrieved 18 July 2016.
• «Osteoporosis». MedlinePlus. U.S. National Library of Medicine.

Osteoporosis
Elderly woman with osteoporosis showing a curved back from compression fractures of her back bones.
Pronunciation	[1][2]
Specialty	Rheumatology, Endocrinology, orthopedics
Symptoms	Increased risk of a broken bone[3]
Complications	Chronic pain[3]
Usual onset	Older age[3]
Risk factors	Alcoholism, anorexia, European or Asian ethnicity, hyperthyroidism, gastrointestinal diseases, surgical removal of the ovaries, kidney disease, smoking, certain medications[3]
Diagnostic method	Dexa Scan( Bone density scan[4])
Treatment	Good diet, exercise, fall prevention, stopping smoking[3]
Medication	Bisphosphonates[5][6]
Frequency	15% (50 year olds), 70% (over 80 year olds)[7]

Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to bone fragility, and consequent increase in fracture risk. It is the most common reason for a broken bone among the elderly.^[3] Bones that commonly break include the vertebrae in the spine, the bones of the forearm, and the hip.^[8] Until a broken bone occurs there are typically no symptoms. Bones may weaken to such a degree that a break may occur with minor stress or spontaneously. After the broken bone heals, the person may have chronic pain and a decreased ability to carry out normal activities.^[3]

Osteoporosis may be due to lower-than-normal maximum bone mass and greater-than-normal bone loss. Bone loss increases after the menopause due to lower levels of estrogen, and after ‘andropause’ due to lower levels of testosterone.^[9][10] Osteoporosis may also occur due to a number of diseases or treatments, including alcoholism, anorexia, hyperthyroidism, kidney disease, and surgical removal of the ovaries. Certain medications increase the rate of bone loss, including some antiseizure medications, chemotherapy, proton pump inhibitors, selective serotonin reuptake inhibitors, and glucocorticosteroids. Smoking, and too little exercise are also risk factors.^[3] Osteoporosis is defined as a bone density of 2.5 standard deviations below that of a young adult. This is typically measured by dual-energy X-ray absorptiometry (DXA or DEXA).^[4]

Prevention of osteoporosis includes a proper diet during childhood, hormone replacement therapy for menopausal women, and efforts to avoid medications that increase the rate of bone loss. Efforts to prevent broken bones in those with osteoporosis include a good diet, exercise, and fall prevention. Lifestyle changes such as stopping smoking and not drinking alcohol may help.^[3] Bisphosphonate medications are useful to decrease future broken bones in those with previous broken bones due to osteoporosis. In those with osteoporosis but no previous broken bones, they are less effective.^{[5][6][needs update][11]} They do not appear to affect the risk of death.^[12]

Osteoporosis becomes more common with age. About 15% of Caucasians in their 50s and 70% of those over 80 are affected.^[7] It is more common in women than men.^[3] In the developed world, depending on the method of diagnosis, 2% to 8% of males and 9% to 38% of females are affected.^[13] Rates of disease in the developing world are unclear.^[14] About 22 million women and 5.5 million men in the European Union had osteoporosis in 2010.^[15] In the United States in 2010, about 8 million women and between 1 and 2 million men had osteoporosis.^[13][16] White and Asian people are at greater risk.^[3] The word «osteoporosis» is from the Greek terms for «porous bones».^[17]

Signs and symptoms[edit]

Osteoporosis itself has no symptoms; its main consequence is the increased risk of bone fractures. Osteoporotic fractures occur in situations where healthy people would not normally break a bone; they are therefore regarded as fragility fractures. Typical fragility fractures occur in the vertebral column, rib, hip and wrist.

Fractures[edit]

Fractures are a common symptom of osteoporosis and can result in disability.^[18] Acute and chronic pain in the elderly is often attributed to fractures from osteoporosis and can lead to further disability and early mortality.^[19] These fractures may also be asymptomatic.^[20] The most common osteoporotic fractures are of the wrist, spine, shoulder and hip. The symptoms of a vertebral collapse («compression fracture») are sudden back pain, often with radicular pain (shooting pain due to nerve root compression) and rarely with spinal cord compression or cauda equina syndrome. Multiple vertebral fractures lead to a stooped posture, loss of height, and chronic pain with resultant reduction in mobility.^[21]

Fractures of the long bones acutely impair mobility and may require surgery. Hip fracture, in particular, usually requires prompt surgery, as serious risks are associated with it, such as deep vein thrombosis and pulmonary embolism. There is also an increased risk of mortality associated with hip surgery, with the mean average mortality rate for Europe being 23.3%, for Asia 17.9%, United States 21% and Australia 24.9%. ^[22]

Fracture risk calculators assess the risk of fracture based upon several criteria, including bone mineral density, age, smoking, alcohol usage, weight, and gender. Recognized calculators include FRAX,^[23] the Garvan FRC calculator and QFracture as well as the open access FREM tool.^[24] The FRAX tool can also be applied in a modification adapted to routinely collected health data.^[25]

The term «established osteoporosis» is used when a broken bone due to osteoporosis has occurred.^[26] Osteoporosis is a part of frailty syndrome.

Risk of falls[edit]

There is an increased risk of falls associated with aging. These falls can lead to skeletal damage at the wrist, spine, hip, knee, foot, and ankle. Part of the fall risk is because of impaired eyesight due to many causes, (e.g. glaucoma, macular degeneration), balance disorder, movement disorders (e.g. Parkinson’s disease), dementia, and sarcopenia (age-related loss of skeletal muscle). Collapse (transient loss of postural tone with or without loss of consciousness). Causes of syncope are manifold, but may include cardiac arrhythmias (irregular heart beat), vasovagal syncope, orthostatic hypotension (abnormal drop in blood pressure on standing up), and seizures. Removal of obstacles and loose carpets in the living environment may substantially reduce falls. Those with previous falls, as well as those with gait or balance disorders, are most at risk.^[27]

Complication[edit]

As well as susceptibility to breaks and fractures, osteoporosis can lead to other complications. Bone fractures which are results from osteoporosis can lead to disability and even an increased chance of death after the injury.^[28]

Depression is considered to a complication of osteoporosis.^[29] People with osteoporosis lose independence and risk being isolated due to less physical activity. This will further hinder the ability to manage health issues.^[29]

Osteoporosis is also linked to respiratory and cardiovascular health issues, such as loss of lung capacity. Multiple fractures lead to a collapsed thoracic spine, which makes less air being able to move into the lungs. Every thoracic vertebral body collapsed results in the loss of nearly 10% of lung volume.^[30]

Risk factors[edit]

Risk factors for osteoporotic fracture can be split between nonmodifiable and (potentially) modifiable. In addition, osteoporosis is a recognized complication of specific diseases and disorders. Medication use is theoretically modifiable, although in many cases, the use of medication that increases osteoporosis risk may be unavoidable.
Caffeine is not a risk factor for osteoporosis.^[31]

Nonmodifiable[edit]

• The most important risk factors for osteoporosis are advanced age (in both men and women) and female sex; estrogen deficiency following menopause or surgical removal of the ovaries is correlated with a rapid reduction in bone mineral density, while in men, a decrease in testosterone levels has a comparable (but less pronounced) effect.^[33][34]
• Ethnicity: While osteoporosis occurs in people from all ethnic groups, European or Asian ancestry predisposes for osteoporosis.^[35]
• Heredity: Those with a family history of fracture or osteoporosis are at an increased risk; the heritability of the fracture, as well as low bone mineral density, is relatively high, ranging from 25 to 80%. At least 30 genes are associated with the development of osteoporosis.^[36]
• Those who have already had a fracture are at least twice as likely to have another fracture compared to someone of the same age and sex.^[37]
• Build: A small stature is also a nonmodifiable risk factor associated with the development of osteoporosis.^[38]

Potentially modifiable[edit]

• Excessive alcohol: Although small amounts of alcohol might be beneficial (bone density increases with increasing alcohol intake, although the link has not been conclusively shown as causal), chronic heavy drinking (alcohol intake greater than three units/day) probably increases fracture risk despite any beneficial effects on bone density.^[39][40]
• Vitamin D deficiency:^[41][42] Low circulating Vitamin D is common among the elderly worldwide.^[4] Mild vitamin D insufficiency is associated with increased parathyroid hormone (PTH) production.^[4] PTH increases bone resorption, leading to bone loss. A positive association exists between serum 1,25-dihydroxycholecalciferol levels and bone mineral density, while PTH is negatively associated with bone mineral density.^[4]
• Tobacco smoking: Many studies have associated smoking with decreased bone health, but the mechanisms are unclear.^[43][44][45] Tobacco smoking has been proposed to inhibit the activity of osteoblasts, and is an independent risk factor for osteoporosis.^[39][46] Smoking also results in increased breakdown of exogenous estrogen, lower body weight and earlier menopause, all of which contribute to lower bone mineral density.^[4]
• Malnutrition: Nutrition has an important and complex role in maintenance of good bone. Identified risk factors include low dietary calcium and/or phosphorus, magnesium, zinc, boron, iron, fluoride, copper, vitamins A, K, E and C (and D where skin exposure to sunlight provides an inadequate supply). Excess sodium is a risk factor. High blood acidity may be diet-related, and is a known antagonist of bone.^[47] Some have identified low protein intake as associated with lower peak bone mass during adolescence and lower bone mineral density in elderly populations.^[4] Conversely, some have identified low protein intake as a positive factor, protein is among the causes of dietary acidity. Imbalance of omega-6 to omega-3 polyunsaturated fats is yet another identified risk factor.^[48]
• A diet high in protein may be optimal for bone health, as higher protein diets tend to increase absorption of calcium from the diet and are associated with higher bone density.^[49][50] No interventional trials have been performed on dietary protein in the prevention and treatment of osteoporosis ^[51] A meta-analysis of published medical studies shows that higher protein diet helps slightly with lower spine density but does not show significant improvement with other bones.^[52]
• Underweight/inactive: Bone remodeling occurs in response to physical stress, so physical inactivity can lead to significant bone loss.^[4] Weight bearing exercise can increase peak bone mass achieved in adolescence,^[4] and a highly significant correlation between bone strength and muscle strength has been determined.^[53] The incidence of osteoporosis is lower in overweight people.^[54]
• Endurance training: In female endurance athletes, large volumes of training can lead to decreased bone density and an increased risk of osteoporosis.^[55] This effect might be caused by intense training suppressing menstruation, producing amenorrhea, and it is part of the female athlete triad.^[56] However, for male athletes, the situation is less clear, and although some studies have reported low bone density in elite male endurance athletes,^[57] others have instead seen increased leg bone density.^[58][59]
• Heavy metals: A strong association between cadmium and lead with bone disease has been established. Low-level exposure to cadmium is associated with an increased loss of bone mineral density readily in both genders, leading to pain and increased risk of fractures, especially in the elderly and in females. Higher cadmium exposure results in osteomalacia (softening of the bone).^[60]
• Soft drinks: Some studies indicate soft drinks (many of which contain phosphoric acid) may increase risk of osteoporosis, at least in women.^[61] Others suggest soft drinks may displace calcium-containing drinks from the diet rather than directly causing osteoporosis.^[62]
• Proton pump inhibitors (such as lansoprazole, esomeprazole, and omeprazole), which decrease the production of stomach acid, are a risk factor for bone fractures if taken for two or more years, due to decreased absorption of calcium in the stomach.^[63]

Medical disorders[edit]

Many diseases and disorders have been associated with osteoporosis.^[64] For some, the underlying mechanism influencing the bone metabolism is straightforward, whereas for others the causes are multiple or unknown.

• In general, immobilization causes bone loss (following the ‘use it or lose it’ rule). For example, localized osteoporosis can occur after prolonged immobilization of a fractured limb in a cast. This is also more common in active people with a high bone turn-over (for example, athletes). Other examples include bone loss during space flight or in people who are bedridden or use wheelchairs for various reasons.^{[citation needed]}
• Hypogonadal states can cause secondary osteoporosis. These include Turner syndrome, Klinefelter syndrome, Kallmann syndrome, anorexia nervosa, andropause,^[65] hypothalamic amenorrhea or hyperprolactinemia.^[65] In females, the effect of hypogonadism is mediated by estrogen deficiency. It can appear as early menopause (<45 years) or from prolonged premenopausal amenorrhea (>1 year). Bilateral oophorectomy (surgical removal of the ovaries) and premature ovarian failure cause deficient estrogen production. In males, testosterone deficiency is the cause (for example, andropause or after surgical removal of the testes).
• Endocrine disorders that can induce bone loss include Cushing’s syndrome,^[4] hyperparathyroidism,^[4] hyperthyroidism,^[4] hypothyroidism, diabetes mellitus type 1 and 2,^[66] acromegaly, and adrenal insufficiency.^[64]
• Malnutrition, parenteral nutrition^[4] and malabsorption can lead to osteoporosis. Nutritional and gastrointestinal disorders that can predispose to osteoporosis include undiagnosed and untreated coeliac disease (both symptomatic and asymptomatic people),^[4][67] Crohn’s disease,^[68] ulcerative colitis,^[68] cystic fibrosis,^[68] surgery^[65] (after gastrectomy, intestinal bypass surgery or bowel resection) and severe liver disease (especially primary biliary cirrhosis).^[65] People with lactose intolerance or milk allergy may develop osteoporosis due to restrictions of calcium-containing foods.^[69] Individuals with bulimia can also develop osteoporosis. Those with an otherwise adequate calcium intake can develop osteoporosis due to the inability to absorb calcium and/or vitamin D. Other micronutrients such as vitamin K or vitamin B₁₂ deficiency may also contribute.
• People with rheumatologic disorders such as rheumatoid arthritis,^[65] ankylosing spondylitis,^[65] systemic lupus erythematosus and polyarticular juvenile idiopathic arthritis are at increased risk of osteoporosis, either as part of their disease or because of other risk factors (notably corticosteroid therapy). Systemic diseases such as amyloidosis and sarcoidosis can also lead to osteoporosis.
• Chronic kidney disease can lead to renal osteodystrophy.^[70]
• Hematologic disorders linked to osteoporosis are multiple myeloma^[65] and other monoclonal gammopathies,^[66] lymphoma, leukemia, mastocytosis,^[65] hemophilia, sickle-cell disease and thalassemia.
• Several inherited or genetic disorders have been linked to osteoporosis. These include osteogenesis imperfecta,^[65] Multicentric carpotarsal osteolysis syndrome,^[71] Multicentric Osteolysis, Nodulosis, and Arthropathy,^[72] Marfan syndrome,^[65] hemochromatosis,^[4] hypophosphatasia^[73] (for which it is often misdiagnosed),^[74] glycogen storage diseases, homocystinuria,^[65] Ehlers–Danlos syndrome,^[65] porphyria, Menkes’ syndrome, epidermolysis bullosa and Gaucher’s disease.
• People with scoliosis of unknown cause also have a higher risk of osteoporosis. Bone loss can be a feature of complex regional pain syndrome. It is also more frequent in people with Parkinson’s disease and chronic obstructive pulmonary disease.
• People with Parkinson’s disease have a higher risk of broken bones. This is related to poor balance and poor bone density.^[75] In Parkinson’s disease there may be a link between the loss of dopaminergic neurons and altered calcium metabolism^[76] (and iron metabolism) causing a stiffening of the skeleton and kyphosis.

Medication[edit]

Certain medications have been associated with an increase in osteoporosis risk; only glucocorticosteroids and anticonvulsants are classically associated, but evidence is emerging with regard to other drugs.

• Steroid-induced osteoporosis (SIOP) arises due to use of glucocorticoids – analogous to Cushing’s syndrome and involving mainly the axial skeleton. The synthetic glucocorticoid prescription drug prednisone is a main candidate after prolonged intake. Some professional guidelines recommend prophylaxis in patients who take the equivalent of more than 30 mg hydrocortisone (7.5 mg of prednisolone), especially when this is in excess of three months.^[77] It is recommended to use calcium or Vitamin D as prevention.^[78] Alternate day use may not prevent this complication.^[79]
• Barbiturates, phenytoin and some other enzyme-inducing antiepileptics – these probably accelerate the metabolism of vitamin D.^[80]
• L-Thyroxine over-replacement may contribute to osteoporosis, in a similar fashion as thyrotoxicosis does.^[64] This can be relevant in subclinical hypothyroidism.
• Several drugs induce hypogonadism, for example aromatase inhibitors used in breast cancer, methotrexate and other antimetabolite drugs, depot progesterone and gonadotropin-releasing hormone agonists.
• Anticoagulants – long-term use of heparin is associated with a decrease in bone density,^[81] and warfarin (and related coumarins) have been linked with an increased risk in osteoporotic fracture in long-term use.^[82]
• Proton pump inhibitors – these drugs inhibit the production of stomach acid; this is thought to interfere with calcium absorption.^[83] Chronic phosphate binding may also occur with aluminium-containing antacids.^[64]
• Thiazolidinediones (used for diabetes) – rosiglitazone and possibly pioglitazone, inhibitors of PPARγ, have been linked with an increased risk of osteoporosis and fracture.^[84]
• Chronic lithium therapy has been associated with osteoporosis.^[64]

Evolutionary[edit]

Age-related bone loss is common among humans due to exhibiting less dense bones than other primate species.^[85] Because of the more porous bones of humans, frequency of severe osteoporosis and osteoporosis related fractures is higher.^[86] The human vulnerability to osteoporosis is an obvious cost but it can be justified by the advantage of bipedalism inferring that this vulnerability is the byproduct of such.^[86] It has been suggested that porous bones help to absorb the increased stress that we have on two surfaces compared to our primate counterparts who have four surfaces to disperse the force.^[85] In addition, the porosity allows for more flexibility and a lighter skeleton that is easier to support.^[86] One other consideration may be that diets today have much lower amounts of calcium than the diets of other primates or the tetrapedal ancestors to humans which may lead to higher likelihood to show signs of osteoporosis.^[87]

Fracture risk assessment[edit]

In the absence of risk factors other than sex and age a BMD measurement using dual-energy X-ray absorptiometry (DXA) is recommended for women at age 65. For women with risk factors a clinical FRAX is advised at age 50.

Pathogenesis[edit]

The underlying mechanism in all cases of osteoporosis is an imbalance between bone resorption and bone formation.^[88][89] In normal bone, matrix remodeling of bone is constant; up to 10% of all bone mass may be undergoing remodeling at any point in time. The process takes place in bone multicellular units (BMUs) as first described by Frost & Thomas in 1963.^[90] Osteoclasts are assisted by transcription factor PU.1 to degrade the bone matrix, while osteoblasts rebuild the bone matrix. Low bone mass density can then occur when osteoclasts are degrading the bone matrix faster than the osteoblasts are rebuilding the bone.^[88][91]

The three main mechanisms by which osteoporosis develops are an inadequate peak bone mass (the skeleton develops insufficient mass and strength during growth), excessive bone resorption, and inadequate formation of new bone during remodeling, likely due to mesenchymal stem cells biasing away from the osteoblast and toward the marrow adipocyte lineage.^[92] An interplay of these three mechanisms underlies the development of fragile bone tissue.^[36] Hormonal factors strongly determine the rate of bone resorption; lack of estrogen (e.g. as a result of menopause) increases bone resorption, as well as decreasing the deposition of new bone that normally takes place in weight-bearing bones. The amount of estrogen needed to suppress this process is lower than that normally needed to stimulate the uterus and breast gland. The α-form of the estrogen receptor appears to be the most important in regulating bone turnover.^[36] In addition to estrogen, calcium metabolism plays a significant role in bone turnover, and deficiency of calcium and vitamin D leads to impaired bone deposition; in addition, the parathyroid glands react to low calcium levels by secreting parathyroid hormone (parathormone, PTH), which increases bone resorption to ensure sufficient calcium in the blood. The role of calcitonin, a hormone generated by the thyroid that increases bone deposition, is less clear and probably not as significant as that of PTH.^[36]

The activation of osteoclasts is regulated by various molecular signals, of which RANKL (receptor activator of nuclear factor kappa-B ligand) is one of the best-studied.^[89] This molecule is produced by osteoblasts and other cells (e.g. lymphocytes), and stimulates RANK (receptor activator of nuclear factor κB). Osteoprotegerin (OPG) binds RANKL before it has an opportunity to bind to RANK, and hence suppresses its ability to increase bone resorption. RANKL, RANK, and OPG are closely related to tumor necrosis factor and its receptors. The role of the Wnt signaling pathway is recognized, but less well understood. Local production of eicosanoids and interleukins is thought to participate in the regulation of bone turnover, and excess or reduced production of these mediators may underlie the development of osteoporosis.^[36] Osteoclast maturation and activity is also regulated by activation of colony stimulating factor 1 receptor (CSF1R).^[93] Menopause-associated increase production of TNF-α stimulates stromal cells to produce colony stimulating factor 1 (CSF-1) which activates CSF1R and stimulates osteoclasts to reabsorb bone.^[94]

Trabecular bone (or cancellous bone) is the sponge-like bone in the ends of long bones and vertebrae. Cortical bone is the hard outer shell of bones and the middle of long bones. Because osteoblasts and osteoclasts inhabit the surface of bones, trabecular bone is more active and is more subject to bone turnover and remodeling. Not only is bone density decreased, but the microarchitecture of bone is also disrupted. The weaker spicules of trabecular bone break («microcracks»), and are replaced by weaker bone. Common osteoporotic fracture sites, the wrist, the hip, and the spine, have a relatively high trabecular bone to cortical bone ratio. These areas rely on the trabecular bone for strength, so the intense remodeling causes these areas to degenerate most when the remodeling is imbalanced.^{[citation needed]} Around the ages of 30–35, cancellous or trabecular bone loss begins. Women may lose as much as 50%, while men lose about 30%.^[38]

• 

  Light micrograph of an osteoclast displaying typical distinguishing characteristics: a large cell with multiple nuclei and a «foamy» cytosol.

• 

  Collapse of vertebra on the right, normal on the left

Diagnosis[edit]

Osteoporosis can be diagnosed using conventional radiography and by measuring the bone mineral density (BMD).^[95] The most popular method of measuring BMD is dual-energy X-ray absorptiometry.^{[citation needed]}

In addition to the detection of abnormal BMD, the diagnosis of osteoporosis requires investigations into potentially modifiable underlying causes; this may be done with blood tests. Depending on the likelihood of an underlying problem, investigations for cancer with metastasis to the bone, multiple myeloma, Cushing’s disease and other above-mentioned causes may be performed.^{[citation needed]}

Conventional radiography[edit]

Conventional radiography is useful, both by itself and in conjunction with CT or MRI, for detecting complications of osteopenia (reduced bone mass; pre-osteoporosis), such as fractures; for differential diagnosis of osteopenia; or for follow-up examinations in specific clinical settings, such as soft tissue calcifications, secondary hyperparathyroidism, or osteomalacia in renal osteodystrophy. However, radiography is relatively insensitive to detection of early disease and requires a substantial amount of bone loss (about 30%) to be apparent on X-ray images.^[96][97]

The main radiographic features of generalized osteoporosis are cortical thinning and increased radiolucency. Frequent complications of osteoporosis are vertebral fractures for which spinal radiography can help considerably in diagnosis and follow-up. Vertebral height measurements can objectively be made using plain-film X-rays by using several methods such as height loss together with area reduction, particularly when looking at vertical deformity in T4-L4, or by determining a spinal fracture index that takes into account the number of vertebrae involved. Involvement of multiple vertebral bodies leads to kyphosis of the thoracic spine, leading to what is known as dowager’s hump.^[98][99]

Dual-energy X-ray[edit]

Dual-energy X-ray absorptiometry (DEXA scan) is considered the gold standard for the diagnosis of osteoporosis. Osteoporosis is diagnosed when the bone mineral density is less than or equal to 2.5 standard deviations below that of a young (30–40-year-old^[4]:58), healthy adult women reference population. This is translated as a T-score. But because bone density decreases with age, more people become osteoporotic with increasing age.^[4]:58 The World Health Organization has established the following diagnostic guidelines:^[4][26]

Category	T-score range	% young women
Normal	T-score ≥ −1.0	85%
Osteopenia	−2.5 < T-score < −1.0	14%
Osteoporosis	T-score ≤ −2.5	0.6%
Severe osteoporosis	T-score ≤ −2.5 with fragility fracture[26]

The International Society for Clinical Densitometry takes the position that a diagnosis of osteoporosis in men under 50 years of age should not be made on the basis of densitometric criteria alone. It also states, for premenopausal women, Z-scores (comparison with age group rather than peak bone mass) rather than T-scores should be used, and the diagnosis of osteoporosis in such women also should not be made on the basis of densitometric criteria alone.^[100]

Biomarkers[edit]

Chemical biomarkers are a useful tool in detecting bone degradation. The enzyme cathepsin K breaks down type-I collagen, an important constituent in bones. Prepared antibodies can recognize the resulting fragment, called a neoepitope, as a way to diagnose osteoporosis.^[101] Increased urinary excretion of C-telopeptides, a type-I collagen breakdown product, also serves as a biomarker for osteoporosis.^[102]

Comparison of bone pathology

view talk edit Condition	Calcium	Phosphate	Alkaline phosphatase	Parathyroid hormone	Comments
Osteopenia	unaffected	unaffected	normal	unaffected	decreased bone mass
Osteopetrosis	unaffected	unaffected	elevated	unaffected[citation needed]	thick dense bones also known as marble bone
Osteomalacia and rickets	decreased	decreased	elevated	elevated	soft bones
Osteitis fibrosa cystica	elevated	decreased	elevated	elevated	brown tumors
Paget’s disease of bone	unaffected	unaffected	variable (depending on stage of disease)	unaffected	abnormal bone architecture

Other measuring tools[edit]

Quantitative computed tomography (QCT) differs from DXA in that it gives separate estimates of BMD for trabecular and cortical bone and reports precise volumetric mineral density in mg/cm³ rather than BMD’s relative Z-score. Among QCT’s advantages: it can be performed at axial and peripheral sites, can be calculated from existing CT scans without a separate radiation dose, is sensitive to change over time, can analyze a region of any size or shape, excludes irrelevant tissue such as fat, muscle, and air, and does not require knowledge of the patient’s subpopulation in order to create a clinical score (e.g. the Z-score of all females of a certain age). Among QCT’s disadvantages: it requires a high radiation dose compared to DXA, CT scanners are large and expensive, and because its practice has been less standardized than BMD, its results are more operator-dependent. Peripheral QCT has been introduced to improve upon the limitations of DXA and QCT.^[95]

Quantitative ultrasound has many advantages in assessing osteoporosis. The modality is small, no ionizing radiation is involved, measurements can be made quickly and easily, and the cost of the device is low compared with DXA and QCT devices. The calcaneus is the most common skeletal site for quantitative ultrasound assessment because it has a high percentage of trabecular bone that is replaced more often than cortical bone, providing early evidence of metabolic change. Also, the calcaneus is fairly flat and parallel, reducing repositioning errors. The method can be applied to children, neonates, and preterm infants, just as well as to adults.^[95] Some ultrasound devices can be used on the tibia.^[103]

Screening[edit]

The U.S. Preventive Services Task Force (USPSTF) recommend that all women 65 years of age or older be screened by bone densitometry.^[104] Additionally they recommend screening younger women with risk factors.^[104] There is insufficient evidence to make recommendations about the intervals for repeated screening and the appropriate age to stop screening.^[105]

In men the harm versus benefit of screening for osteoporosis is unknown.^[104] Prescrire states that the need to test for osteoporosis in those who have not had a previous bone fracture is unclear.^[106] The International Society for Clinical Densitometry suggest BMD testing for men 70 or older, or those who are indicated for risk equal to that of a 70‑year‑old.^[107] A number of tools exist to help determine who is reasonable to test.^[108]

Prevention[edit]

Lifestyle prevention of osteoporosis is in many aspects the inverse of the potentially modifiable risk factors.^[109] As tobacco smoking and high alcohol intake have been linked with osteoporosis, smoking cessation and moderation of alcohol intake are commonly recommended as ways to help prevent it.^[110]

In people with coeliac disease adherence to a gluten-free diet decreases the risk of developing osteoporosis^[111] and increases bone density.^[67] The diet must ensure optimal calcium intake (of at least one gram daily) and measuring vitamin D levels is recommended, and to take specific supplements if necessary.^[111]

Nutrition[edit]

Studies of the benefits of supplementation with calcium and vitamin D are conflicting, possibly because most studies did not have people with low dietary intakes.^[112] A 2018 review by the USPSTF found low-quality evidence that the routine use of calcium and vitamin D supplements (or both supplements together) did not reduce the risk of having an osteoporotic fracture in male and female adults living in the community who had no known history of vitamin D deficiency, osteoporosis, or a fracture.^[113] The USPSTF does not recommend low dose supplementation (less than 1 g of calcium and 400 IU of vitamin D) in postmenopausal women as there does not appear to be a difference in fracture risk.^[114] A 2015 review found little data that supplementation of calcium decreases the risk of fractures.^[115] While some meta-analyses have found a benefit of vitamin D supplements combined with calcium for fractures, they did not find a benefit of vitamin D supplements (800 IU/day or less) alone.^[116][117] While supplementation does not appear to affect the risk of death,^[113][117] an increased risk of myocardial infarctions ^[118][119] kidney stones,^[113] and stomach problems^[117] is associated with calcium supplementation.

Vitamin K deficiency is also a risk factor for osteoporotic fractures.^[120] The gene gamma-glutamyl carboxylase (GGCX) is dependent on vitamin K. Functional polymorphisms in the gene could attribute to variation in bone metabolism and BMD. ^[121] Vitamin K2 is also used as a means of treatment for osteoporosis and the polymorphisms of GGCX could explain the individual variation in the response to treatment of vitamin K.^[122]

Dietary sources of calcium include dairy products, leafy greens, legumes, and beans.^[123] There has been conflicting evidence about whether or not dairy is an adequate source of calcium to prevent fractures. The National Academy of Sciences recommends 1,000 mg of calcium for those aged 19–50, and 1,200 mg for those aged 50 and above.^[124] A review of the evidence shows no adverse effect of higher protein intake on bone health.^[125]

Physical exercise[edit]

There is limited evidence indicating that exercise is helpful in promoting bone health.^[126] There is some evidence that physical exercise may be beneficial for bone density in postmenopausal women and lead to a slightly reduced risk of a bone fracture (absolute difference 4%).^[127] Weight bearing exercise has been found to cause an adaptive response in the skeleton.^[128] Weight bearing exercise promotes osteoblast activity, protecting bone density.^[129] A position statement concluded that increased bone activity and weight-bearing exercises at a young age prevent bone fragility in adults.^[130] Bicycling and swimming are not considered weight-bearing exercise. Neither contribute to slowing bone loss with age, and professional bicycle racing has a negative effect on bone density.^[131]

Low-quality evidence suggests that exercise may reduce pain and improve quality of life of people with vertebral fractures and there is moderate-quality evidence that exercise will likely improve physical performance in individuals with vertebral fractures.^[132]

Physical therapy[edit]

People with osteoporosis are at higher risk of falls due to poor postural control, muscle weakness, and overall deconditioning.^[133] Postural control is important to maintaining functional movements such as walking and standing. Physical therapy may be an effective way to address postural weakness that may result from vertebral fractures, which are common in people with osteoporosis. Physical therapy treatment plans for people with vertebral fractures include balance training, postural correction, trunk and lower extremity muscle strengthening exercises, and moderate-intensity aerobic physical activity.^[132] The goal of these interventions are to regain normal spine curvatures, increase spine stability, and improve functional performance.^[132] Physical therapy interventions were also designed to slow the rate of bone loss through home exercise programs.^[133]

Whole body vibration therapy has also been suggested as a physical therapy intervention. Moderate to low-quality evidence indicates that whole body vibration therapy may reduce the risk of falls.^[134] There are conflicting reviews as to whether vibration therapy improves bone mineral density.^[134][135]

Physical therapy can aid in overall prevention in the development of osteoporosis through therapeutic exercise. Prescribed amounts of mechanical loading or increased forces on the bones promote bone formation and vascularization in various ways, therefore offering a preventative measure that is not reliant on drugs. Specific exercise interacts with the body’s hormones and signaling pathways which encourages the maintenance of a healthy skeleton.^[136]

Hormone therapy[edit]

Reduced oestrogen levels increase the risk of osteoporosis, so hormone replacement therapy when women reach the menopause may reduce the incidence of osteoporosis.

Management[edit]

Lifestyle[edit]

Weight-bearing endurance exercise and/or exercises to strengthen muscles improve bone strength in those with osteoporosis.^[127][137] Aerobics, weight bearing, and resistance exercises all maintain or increase BMD in postmenopausal women.^[127] Fall prevention can help prevent osteoporosis complications. There is some evidence for hip protectors specifically among those who are in care homes.^[138]

Pharmacologic therapy[edit]

The US National Osteoporosis Foundation recommends pharmacologic treatment for patients with hip of spine fracture thought to be related to osteoporosis, those with BMD 2.5 SD or more below the young normal mean (T-score -2.5 or below), and those with BMD between 1 and 2.5 SD below normal mean whose 10-year risk, using FRAX, for hip fracture is equal or more than 3%.^[139]
Bisphosphonates are useful in decreasing the risk of future fractures in those who have already sustained a fracture due to osteoporosis.^{[5][6][110][140]} This benefit is present when taken for three to four years.^[141][142] They do not appear to change the overall risk of death.^[12] Tentative evidence does not support the use of bisphosphonates as a standard treatment for secondary osteoporosis in children.^[142] Different bisphosphonates have not been directly compared, therefore it is unknown if one is better than another.^[110] Fracture risk reduction is between 25 and 70% depending on the bone involved.^[110] There are concerns of atypical femoral fractures and osteonecrosis of the jaw with long-term use, but these risks are low.^[110][143] With evidence of little benefit when used for more than three to five years and in light of the potential adverse events, it may be appropriate to stop treatment after this time.^[141] One medical organization recommends that after five years of medications by mouth or three years of intravenous medication among those at low risk, bisphosphonate treatment can be stopped.^[144][145] In those at higher risk they recommend up to ten years of medication by mouth or six years of intravenous treatment.^[144]

The goal of osteoporosis management is to prevent osteoporotic fractures, but for those who have sustained one already it is more urgent to prevent a secondary fracture.^[146] That is because patients with a fracture are more likely to experience a recurrent fracture, with marker increase in morbidity and mortality compared.^[146] Among the five bisphosphonates, no significant differences were found for a secondary fracture for all fracture endpoints combined.^[146] That being said, alendronate was identified as the most efficacious for secondary prevention of vertebral and hip fractures while zoledronate showed better performance for nonvertebral non-hip fracture prevention.^[146] There is concern that many people do not receive appropriate pharmacological therapy after a low-impact fracture.^[147]

For those with osteoporosis but who have not had a fracture, evidence does not support a reduction in fracture risk with risedronate^[6] or etidronate.^[11] Alendronate decreases fractures of the spine but does not have any effect on other types of fractures.^[5] Half stop their medications within a year.^[148] When on treatment with bisphosphonates rechecking bone mineral density is not needed.^[145] There is tentative evidence of benefit in males with osteoporosis.^[149]

Fluoride supplementation does not appear to be effective in postmenopausal osteoporosis, as even though it increases bone density, it does not decrease the risk of fractures.^[150][151]

Teriparatide (a recombinant parathyroid hormone) has been shown to be effective in treatment of women with postmenopausal osteoporosis.^[152][140] Some evidence also indicates strontium ranelate is effective in decreasing the risk of vertebral and nonvertebral fractures in postmenopausal women with osteoporosis.^[153] Hormone replacement therapy, while effective for osteoporosis, is only recommended in women who also have menopausal symptoms.^[110] It is not recommended for osteoporosis by itself.^[145] Raloxifene, while effective in decreasing vertebral fractures, does not affect the risk of nonvertebral fracture.^[110] And while it reduces the risk of breast cancer, it increases the risk of blood clots and strokes.^[110] While denosumab is effective at preventing fractures in women,^[110] there is not clear evidence of benefit in males.^[149] In hypogonadal men, testosterone has been shown to improve bone quantity and quality, but, as of 2008, no studies evaluated its effect on fracture risk or in men with a normal testosterone levels.^[66] Calcitonin while once recommended is no longer due to the associated risk of cancer and questionable effect on fracture risk.^[154] Alendronic acid/colecalciferol can be taken to treat this condition in post-menopausal women.^[155]

Romosozumab (sold under the brand name Evenity) is a monoclonal antibody against sclerostin. Romosozumab is usually reserved for patients with very high fracture risk and is the only available drug therapy for osteoporosis that leads to simultaneous inhibition of bone resorption together with an anabolic effect.^[156][157]

Certain medications like alendronate, etidronate, risedronate, raloxifene, and strontium ranelate can help to prevent osteoporotic fragility fractures in postmenopausal women with osteoporosis.^[158] Tentative evidence suggests that Chinese herbal medicines may have potential benefits on bone mineral density.^[159]

Prognosis[edit]

Hip fractures per 1000 person-years^[160]

WHO category	Age 50–64	Age > 64	Overall
Normal	5.3	9.4	6.6
Osteopenia	11.4	19.6	15.7
Osteoporosis	22.4	46.6	40.6

Although people with osteoporosis have increased mortality due to the complications of fracture, the fracture itself is rarely lethal.

Hip fractures can lead to decreased mobility and additional risks of numerous complications (such as deep venous thrombosis and/or pulmonary embolism, and pneumonia). The six-month mortality rate for those aged 50 and above following hip fracture was found to be around 13.5%, with a substantial proportion (almost 13%) needing total assistance to mobilize after a hip fracture.^[161]

Vertebral fractures, while having a smaller impact on mortality, can lead to severe chronic pain of neurogenic origin, which can be hard to control, as well as deformity. Though rare, multiple vertebral fractures can lead to such severe hunchback (kyphosis), the resulting pressure on internal organs can impair one’s ability to breathe.

Apart from risk of death and other complications, osteoporotic fractures are associated with a reduced health-related quality of life.^[162]

The condition is responsible for millions of fractures annually, mostly involving the lumbar vertebrae, hip, and wrist. Fragility fractures of ribs are also common in men.

Fractures[edit]

Hip fractures are responsible for the most serious consequences of osteoporosis. In the United States, more than 250,000 hip fractures annually are attributable to osteoporosis.^[163] A 50-year-old white woman is estimated to have a 17.5% lifetime risk of fracture of the proximal femur. The incidence of hip fractures increases each decade from the sixth through the ninth for both women and men for all populations. The highest incidence is found among men and women ages 80 or older.^[164]

Between 35 and 50% of all women over 50 had at least one vertebral fracture. In the United States, 700,000 vertebral fractures occur annually, but only about a third are recognized. In a series of 9704 women aged 68.8 on average studied for 15 years, 324 had already sustained a vertebral fracture at entry into the study and 18.2% developed a vertebral fracture, but that risk rose to 41.4% in women who had a previous vertebral fracture.^[165]

In the United States, 250,000 wrist fractures annually are attributable to osteoporosis.^[163] Wrist fractures are the third most common type of osteoporotic fractures. The lifetime risk of sustaining a Colles’ fracture is about 16% for white women. By the time women reach age 70, about 20% have had at least one wrist fracture.^[164]

Fragility fractures of the ribs are common in men as young as age 35.^{[citation needed]} These are often overlooked as signs of osteoporosis, as these men are often physically active and develop the fracture in the course of physical activity, such as falling while water skiing or jet skiing.

Epidemiology[edit]

This article needs to be updated. Please help update this article to reflect recent events or newly available information. (December 2020)

It is estimated that 200 million people have osteoporosis.^[167] Osteoporosis becomes more common with age.^[3] About 15% of Caucasians in their 50s and 70% of those over 80 are affected.^[7] It is more common in women than men.^[3] In the developed world, depending on the method of diagnosis, 2% to 8% of males and 9% to 38% of females are affected.^[13] Rates of disease in the developing world are unclear.^[14]

Postmenopausal women have a higher rate of osteoporosis and fractures than older men.^[168] Postmenopausal women have decreased estrogen which contributes to their higher rates of osteoporosis.^[168] A 60-year-old woman has a 44% risk of fracture while a 60-year-old man has a 25% risk of fracture.^[168]

There are 8.9 million fractures worldwide per year due to osteoporosis.^[169] Globally, 1 in 3 women and 1 in 5 men over the age of 50 will have an osteoporotic fracture.^[169] Data from the United States shows a decrease in osteoporosis within the general population and in white women, from 18% in 1994 to 10% in 2006.^[170] White and Asian people are at greater risk.^[3] People of African descent are at a decreased risk of fractures due to osteoporosis, although they have the highest risk of death following an osteoporotic fracture.^[170]

It has been shown that latitude affects risk of osteoporotic fracture.^[166] Areas of higher latitude such as Northern Europe receive less Vitamin D through sunlight compared to regions closer to the equator, and consequently have higher fracture rates in comparison to lower latitudes.^[166] For example, Swedish men and women have a 13% and 28.5% risk of hip fracture by age 50, respectively, whereas this risk is only 1.9% and 2.4% in Chinese men and women.^[170] Diet may also be a factor that is responsible for this difference, as vitamin D, calcium, magnesium, and folate are all linked to bone mineral density.^[171]

There is also an association between Celiac Disease and increased risk of osteoporosis.^[172] In studies with premenopausal females and males, there was a correlation between Celiac Disease and osteoporosis and osteopenia.^[172] Celiac Disease can decrease absorption of nutrients in the small intestine such as calcium, and a gluten-free diet can help people with Celiac Disease to revert to normal absorption in the gut.^[173]

About 22 million women and 5.5 million men in the European Union had osteoporosis in 2010.^[15] In the United States in 2010 about 8 million women and one to 2 million men had osteoporosis.^[13][16] This places a large economic burden on the healthcare system due to costs of treatment, long-term disability, and loss of productivity in the working population. The EU spends 37 billion euros per year in healthcare costs related to osteoporosis, and the US spends an estimated US$19 billion annually for related healthcare costs.^[169]

History[edit]

The link between age-related reductions in bone density goes back to the early 1800s. French pathologist Jean Lobstein coined the term osteoporosis.^[17] The American endocrinologist Fuller Albright linked osteoporosis with the postmenopausal state.^[174]

Anthropologists have studied skeletal remains that showed loss of bone density and associated structural changes that were linked to a chronic malnutrition in the agricultural area in which these individuals lived. «It follows that the skeletal deformation may be attributed to their heavy labor in agriculture as well as to their chronic malnutrition», causing the osteoporosis seen when radiographs of the remains were made.^[175]

See also[edit]

• Spaceflight osteopenia
• World Osteoporosis Day

References[edit]

External links[edit]

• Handout on Health: Osteoporosis  – US National Institute of Arthritis and Musculoskeletal and Skin Diseases
• Osteoporosis  – l NIH Osteoporosis and Related Bone Diseases – National Resource Center
• Office of the Surgeon General (2004). Bone Health and Osteoporosis: A Report of the Surgeon General. Rockville, MD: U.S. Department of Health and Human Services. PMID 20945569. Retrieved 18 July 2016.
• «Osteoporosis». MedlinePlus. U.S. National Library of Medicine.



Остеопороз

Симптомы остеопороза, лечение и меры профилактики

Остеопороз – разрежение кортикального и губчатого слоя кости, происходящее в результате частичного растворения костного вещества. Название заболевания произошло от греческих слов: osteo – кость и poros – пора, дыра, отверстие. Хрупкость костной ткани, вызванная снижением удельного веса кости в единице объема, обусловлена нарушением обменных процессов в организме, отвечающих за усвоение микроэлемента кальция. Рассмотрим подробнее, почему появляется остеопороз, что это такое и как лечить болезнь средствами традиционной и народной медицины?

Патология чаще встречается у дам в период менопаузы (до 80% случаев). Бедственность положения пациентов с остеопорозом заключается в том, что даже при незначительных травмах и компрессионных нагрузках у них возникают переломы костей. Процесс разрушения костей прогрессирует с каждым годом, ограничивая подвижность больных и снижая качество жизни. Ряд мероприятий помогает остановить процесс и предупредить возникновение переломов и трещин.

Что это такое?

Остеопороз — хронически прогрессирующее системное обменное заболевание скелета или клинический синдром, проявляющийся при других заболеваниях, который характеризуется снижением плотности костей, нарушением их микроархитектоники и усиление хрупкости по причине нарушения метаболизма костной ткани с преобладанием катаболизма над процессами костеобразования, снижением прочности кости и повышением риска переломов.

Это определение относит остеопороз к болезням костно-мышечной системы и соединительной ткани (МКБ-10) и дополняет его понятием «метаболическое или обменное заболевание». 

Причины возникновения

В развитии остеопороза играет роль нарушение равновесия в ремодулировании костной ткани. В процессе постоянного обновления костной ткани участвуют клетки – остеокласты и остеобласты. Один остеокласт разрушает столько костной массы, сколько формирует 100 остеобластов. Для заполнения (минерализации) костных лакун, вызванных остеокластами за 10 суток остеобластам требуется 80 суток.

При повышении активности остеокластов (по разным причинам) разрушение костной ткани происходит быстрее, чем ее формирование. Истончаются и перфорируются трабекулярные пластинки, происходит деструкция горизонтальных связей, увеличивается ломкость кости, хрупкость – что грозит переломами костей.

Рассмотрим детальные факторы риска.

Эндокринологические:

• позднее менархе;
• любой гормональный дисбаланс;
• ранняя менопауза (постовариэктомическая в том числе);
• периоды аменореи в анамнезе до менопаузы;
• все виды бесплодия.

Генетические:

• пожилой и преклонный возраст (старость);
• женский пол (риск остеопороза для мужчин в три раза меньше, чем для женщин);
• принадлежность к европеоидной или монголоидной расе;
• наличие остеопороза, патологических переломов и/или переломов шейки бедренной кости и позвонков у близких родственников;
• низкий пик костной массы (рассчитывается объективно);
• хрупкое телосложение (субъективно);
• большая длина шейки бедренной кости относительно диафиза;
• низкий вес (до 56 кг европеоидные женщины и до 50 кг азиатки, до 70 кг мужчины обеих рас);
• критический рост (для женщин выше 172 см, для мужчин — 183 см);
• отсутствие генерализованного остеоартроза;

Обусловленные образом жизни:

• табакокурение;
• избыточная физическая нагрузка;
• длительное парентеральное питание;
• алиментарный дефицит кальция (недостаток минерала в пище или нарушение его всасывания);
• злоупотребление алкоголем (алкоголизм);
• адинамия, недостаточная физическая активность (уменьшение стимуляции наращивания костной массы мышечной системой);
• гиповитаминоз D (недостаток витамина в пище или проживание в северных регионах).

Факторы, обусловленные длительным приемом медицинских препаратов:

• противосудорожных средств (фенитоин и др.);
• лития;
• для лечения опухолей (цитостатики, цитотоксины);
• метатрексата, циклоспорина А;
• глюкокортикоидов (в перерасчете на преднизолон ≥ 7,5 мг в сутки полгода и более);
• тиреоидных гормонов (L-тироксин и др.);
• антикоагулянтов (прямые, непрямые);
• антибиотиков тетрациклинового ряда;
• фосфат-связывающих антацидов;
• агонистов и антагонистов гонадотропного гормона и его рилизинг фактора.

Факторы, обусловленные сопутствующей патологией:

• системы пищеварения (нарушение абсорбции);
• хронической недостаточностью кровообращения;
• хронической почечной недостаточностью;
• состоянием после трансплантации органов;
• эндокринной (гиперпаратиреоз, тиреотоксикоз, гиперпролактинемия, сахарный диабет, синдром Кушинга, первичный гипогонадизм, болезнь Аддисона);
• системы крови и органов кроветворения (лейкоз, множественная миелома, лимфома, пернициозная анемия);
• системными аутоаллергиями (ревматоидный артрит, болезнь Бехтерева, полимиозит, системная красная волчанка и др.).

Таким образом, появление остеопороза будет вполне ожидаемым, если знать все причины, которые окажут влияние на формирование представленного недуга.

Остеопороз сенильного типа возникает из-за дефицита кальция, связанного с возрастом и потерей баланса между форсированностью разрушения костных тканей, а также скоростью образования новой ткани костного типа. «Сенильный» подразумевает, что представленное состояние образуется в более старшем возрасте, чаще всего у людей от 70-ти лет и более. Данный недуг в два раза чаще формируется у женщин, чем у представителей мужского пола. У женщин он практически всегда сочетается с постменопаузальным этапом.

Следует особенно отметить то, что меньше чем в 5% случаев заболевание обусловлено каким-либо другим недугом или приемом некоторых лекарственных средств. Это форма остеопороза, известная как вторичная. Он может формироваться при состояниях, которые были обозначены выше. Допустим, проблемы с почками или эндокринной железой. Излишне активное употребление алкоголя и пристрастие к курению лишь усугубляют представленное заболевание.

Существует также идиопатический «молодежный» остеопороз. Это редчайший вид остеопороза, причина которого на данный момент остается неизвестной. Он формируется у младенцев, детей и людей молодого возраста, которые обладают вполне нормальным уровнем гормонов и витаминов в крови. К тому же, у них не наблюдается какой-либо понятной причины снижения степени плотности костных тканей.

Классификация

В зависимости от причин его подразделяют на первичный как результат естественного старения организма, и вторичный.

Виды первичного остеопороза:

• Остеопороз взрослых
• Идиопатический (причины не установлены). Он может развиваться в любом возрасте
• Постменопаузальный (у женщин)
• Ювенильный (подростковый)
• Сенильный ( старческий)

Виды вторичного остеопороза — это обусловленный:

• Болезнями крови.
• Заболеваниями пищеварительного тракта, способствующими нарушению всасывания кальция.
• Заболеваниями почек (синдром Фанкони, хроническая почечная недостаточность).
• Эндокринными заболеваниями (уменьшение синтеза половых гормонов, нарушение функции щитовидной, паращитовидных, поджелудочной желез, надпочечников).
• Заболеваниями соединительной ткани (ревматизм, системная красная волчанка, остеоартроз, ревматоидный артрит).
• Другими заболеваниями, приводящими к костным разрушениям.

Что происходит с костью при остеопорозе?

Кость по своему строению может быть двух видов: компактной и губчатой. Компактная ткань очень плотная, имеет однородную структуру и состоит из расположенных концентрически костных пластинок. Именно компактное вещество покрывает все кости снаружи. Толще всего слой компактного вещества в средней части длинных, так называемых трубчатых костей: это, например, бедренная кость, кости голени (большеберцовая и малоберцовая), плечевая, локтевая, лучевая кость. Наглядно это показано на картинке чуть ниже.

Головки костей, а также плоские и короткие кости имеют очень тонкий слой компактного вещества, под которым находится губчатое костное вещество. Губчатое вещество само по себе имеет пористое строение благодаря тому, что состоит из костных пластинок, располагающихся друг к другу под углом и образующих своеобразные ячейки.

Губчатое вещество здоровой кости имеет хорошо выраженные костные пластинки и небольшие поры. Пластинки губчатой ткани расположены не хаотично, а соответственно тому, в каком направлении кость испытывает наибольшие нагрузки (например, при сокращении мышц).

При остеопорозе костная ткань теряет свою минеральную составляющую, в результате чего костные пластинки истончаются или пропадают вовсе. Это приводит и к уменьшению толщины компактного и разрежению губчатого вещества.

В итоге изменяется не только сама минеральная плотность кости, но и, что немаловажно, строение костной ткани. Пластинки перестают выстраиваться по линиям сжатия-растяжения, что существенно уменьшает устойчивость кости к нагрузкам.

Первые признаки

Ранние симптомы остеопороза у женщин после 50 лет:

• ломота, ноющая болезненность в костях, особенно при смене погоды;
• развитие пародонтоза и изменение ногтей;
• быстрая утомляемость, эпизоды учащенного сердцебиения;
• раннее появление седых волос;
• судорожные сокращения мышц голеней по ночам, особенно у женщин.

Симптомы остеопороза

Опасность клинической картины связана с бессимптомным или малосимптомным началом остеопороза, маскирующимся под остеохондроз позвоночника и артрозы суставов. Заболевание часто диагностируется уже при наличии перелома. А переломы могут возникать при минимальной травме, поднятии тяжести.

Заметить женщине симптомы остеопороза на ранней стадии достаточно сложно, хотя существует несколько признаков. Например, изменения в осанке, боли в костях при изменении погоды, хрупкие ногти и волосы, разрушение зубов. Наиболее чувствительны к заболеванию позвоночник, шейка бедра, кости рук и запястье. Первыми симптомами остеопороза могут быть боли в поясничном и грудном отделах позвоночника при длительной статической нагрузке (например, сидячей работе), ночные судороги в ногах, хрупкость ногтей, старческая сутулость, уменьшение роста (за счет уменьшения высоты позвонков), явления пародонтоза.

Постоянные боли в спине, пояснице, межлопаточной области могут быть симптомами остеопороза. При наличии болей, уменьшении роста, изменении осанки нужно проконсультироваться у врача, обследоваться на наличие остеопороза. 

Диагностика

Установить точный диагноз только на основании жалоб больного невозможно. Ведь под признаками остеопороза могут маскироваться и другие болезни опорно-двигательного аппарата, требующие иного подхода к лечению.

Современные возможности диагностики позволяют решить сразу несколько задач: выявить наличие остеопороза и его последствия, оценить степень остеопении, а также определить возможную причину этой патологии.

Методики диагностики остеопороза:

1. МРТ и КТ.
2. Осмотр у ортопеда (хирурга, невропатолога).
3. Изотопная абсорбциометрия.
4. Общий и биохимический анализ мочи.
5. Исследование гормонального статуса.
6. Рентгеновская или ультразвуковая денситометрия костной ткани (оценивается минеральная плотность костей).
7. Общий и биохимический анализ крови (с указанием концентрации кальция, фосфора, магния и других показателей).
8. Определение суточного выделения кальция почками (оценивается степень всасывания этого микроэлемента в структурах пищеварительного тракта).
9. Рентгенография скелета (в нескольких проекциях для получения более четкой картины, метод эффективен при утрате более трети костной массы).

Ведущим методом оценки потери костной массы в диагностике остеопороза является костная денситометрия. Этот метод позволяет достаточно точно измерить костную массу, оценить структурную плотность тканей кости и определить степень остеопении. В большинстве европейских стран денситометрию рекомендуют проводить каждые два года всем женщинам старше 45 лет, а мужчинам – с 50 лет. Если имеются какие-либо факторы риска по формированию остеопороза, начинать проводить это обследование следует раньше.

Как лечить остеопороз?

Современное лечение остеопороза у женщин является комплексным мероприятием и неотделимо от правильного питания, употребления витамина D, препаратов, содержащих фосфорно – кальциевые добавки. Наиболее известными являются следующие способы лечения:

1. Применение бифосфонатов, например, алиндроната. Этот препарат препятствует разрушению костной ткани и почти вдвое снижает риск возникновения патологических переломов;
2. Применение препарата «Миакальцик», который представляет собой природный аналог кальцитонина, улучшающего фосфорно – кальциевый обмен;
3. Эффективным методом лечения остеопороза у женщин обладает заместительная гормональная терапия, которая проводится после наступления менопаузы. Эстрогеновая терапия должна проводиться только после тщательного обследования гинекологом, маммологом и учета выраженности побочных эффектов, самым частым из которых является венозный тромбоз.

Кроме вышеперечисленных методов лечения, пациентам с остеопорозом показана специальная безнагрузочная ЛФК, а так же умеренный массаж.

Бисфосфонаты для лечения остеопороза

На данный момент бисфосфонаты следует считать признанным способом профилактики и лечения остеопороза не только у женщин, но и у мужчин. Исследования, которые были успешно проведены на многих тысячах пациентов, продемонстрировали, что бисфосфонаты:

• угнетают костную резервацию;
• положительно воздействуют на увеличение минеральной плотности костных тканей (МПК);
• абсолютно не опасны;
• отлично переносятся человеческим организмом;
• обладают малым количеством побочных эффектов;
• уменьшают вероятность возникновения переломов.

На сегодняшний день в активной практике применяется лишь определенное количество бисфосфонатов, а именно алендронат, ризендронат, ибондронат, золедриновая кислота. Они характеризуются самыми разными путями и способами внедрения в организм.

Самым известным и отлично изученным бисфосфонатом следует считать алиндронат. Его степень эффективности доказана в многочисленных обследованиях у тех, кто болен остеопорозом. Исследования осуществлялись и при наличии переломов в области позвонков.

Также данный препарат эффективен в процессе профилактики остеопороза у женщин в постменопаузальном периоде с остеопенией. В среднем алиндронат уменьшает вероятность формирования переломов самых разных локализации на 50%, а вероятность более специфических переломов в области позвонков — на 90%.

Данное лекарственное средство прописывается в дозировке 70 мг, то есть одна таблетка, раз в неделю. При остеопорозе постменопаузального типа также используется ризендронат в дозировке 30 мг в неделю.

Диета и правила питания

Основные принципы питания при остеопорозе укладываются в очень простую схему: пища должна обеспечивать необходимое количество кальция и витамина D. Последний необходим для правильного усвоения кальция. Кроме того, улучшают усвоение кальция также калий, фосфор и магний.

Пациентам с диагностированным остеопорозом нужно исключить из рациона:

• любые продукты из зерен какао и кофе;
• алкогольные напитки;
• сахар – его можно заменить медом;
• кондитерские изделия;
• газированные напитки, которые в своем составе содержат кофеин – например, знаменитые энергетики;
• маргарин, майонез и любые жирные соусы – лучше заменить их сметаной или соусом из оливкового масла/горчицы и бальзамического уксуса;
• бараний и говяжий жиры – при употреблении мяса этих видов нужно выбирать постные кусочки.

К разрешенным продуктам при остеопорозе относятся:

• Зелень и листовые виды овощей.
• Фрукты, ягоды абсолютно всех видов.
• Все виды орехов и семечек.
• Все виды грибов. По данным научных исследований самое высокое содержание кальция выявлено в белых грибах.
• Бобовые.
• Макаронные изделия.
• Масла растительные рафинированные.
• Морепродукты. Креветки, мидии, осьминоги, кальмары – эти представители морского мира в своем химическом составе имеют достаточно высокое количество кальция. В крайнем случае, нужно регулярно употреблять морскую капусту – она еще богата и йодом.
• Рыба. Необходимо вводить в рацион и речную, и морскую рыбу, так как они обладают разными составами. Не стоит ее жарить, лучше проварить, приготовить на пару или протушить.
• Яйца. Можно употреблять в пищу и куриные, и перепелиные яйца – они будут одинаково полезны людям с остеопорозом.
• Овощи. К употреблению допускаются абсолютно все виды овощей, в том числе помидоры, кабачки, тыква. Если любите жареные овощи, то используйте для этого гриль, а готовить тушеные блюда из овощей лучше с использованием минимального количества растительного масла.
• Мясо всех видов. Очень полезно вводить в рацион больного остеопорозом крольчатину и индейку.
• Молочные продукты. Тут сомнений и быть не должно – кефир и творог, сметана и сливки, сыворотка и ряженка отличаются повышенным содержанием кальция. Но следует обратить внимание на жирность продуктов – она должна быть низкой.

Правила употребления пищи в рамках диеты при остеопорозе:

• лучше употреблять пищу, приготовленную в домашних условиях;
• в день должно быть не менее 5 приемов пищи;
• перерыв между едой должен составлять не более 3, 5 часов;
• перекусы в кафе замените йогуртами и свежими фруктами (яблоко, банан);
• нельзя сочетать в одном блюде мясо и крупы;
• смело можно есть мясо вместе с овощами;
• нельзя устраивать монодиету – например, целый день есть только молочные продукты или овощию

Исключительно диета не даст хороших результатов – она должна быть лишь одним составляющим при лечении остеопороза. 

Модификация образа жизни

Лечение и профилактика остеопороза невозможны без изменения образа жизни и избавления от факторов риска этой болезни и ее осложнений. Медикаментозные или другие методы лечения остеопороза важно и нужно дополнять модификацией своего образа жизни.

Основные рекомендации Всемирной организации здравоохранения для пациентов с риском остеопоротических переломов:

• ведение постоянного активного образа жизни;
• достаточное пребывание на солнце и на свежем воздухе;
• отказ от табакокурения и избыточного употребления алкоголя;
• соблюдение индивидуальных норм содержания кальция и витамина D в продуктах питания, а в случае необходимости, восполнять дефицит лекарственными препаратами;
• поддерживать индекс массы тела не менее 19 кг/м2, так как низкая масса тела – это серьезный риск переломов;
• соблюдать здоровый режим сна;
• регулярно посещать морские курорты и санатории.

При грамотно составленной лечебной программе, которая будет учитывать все индивидуальные особенности пациента, причину нарушения минерализации костей и факторы риска, а также при адекватных профилактических мероприятиях прогресс остеопороза можно значительно замедлить, а иногда и остановить.

Прогноз

Прогноз на выздоровление зависит от степени и своевременности выявления остеопении и правильности коррекции этого патологического состояния.

Поскольку остеопороз считается заболеванием пожилых людей, к сожалению, избежать данного недуга не всегда удается. Главная опасность при остеопорозе – это травмы и их последствия. Но медики склонны утверждать, что далеко не во всех случаях остеопороз является «сопровождением» старости. Чтобы болезнь не коснулась, следует соблюдать меры профилактики и тщательно следить за своим здоровьем.

Также важно учитывать наличие фоновых заболеваний или состояний, ведущих к развитию этой патологии, и при лечении остеопороза костей производить их адекватную коррекцию. При устранении таких факторов риска прогноз становится более благоприятным.

Профилактика

Как предотвратить остеопороз или остановить его дальнейшее прогрессирование? Необходимо придерживаться таких правил:

1. Нужно максимально ограничить потребление кофе, чая, алкогольных напитков.
2. Необходимо, чтобы каждый день присутствовала определенная двигательная активность.
3. Рекомендуется заниматься физкультурой и спортом, но избегать слишком интенсивных нагрузок.
4. Ограничить употребление продуктов, содержащих фосфор. Это красное мясо, любые сладкие напитки с газом.
5. Рациональное питание, которое подразумевает употребление продуктов, содержащих большое количество кальция. К таким относят молоко, кефир, сыр, творог, брокколи.

Также нужно не забывать о профилактическом обследовании организма, которое позволит своевременно выявить проблемы с функционированием двигательной системы и предупредить опасные для жизни последствия.

Около 14 млн человек в России страдают остеопорозом, а еще у 20 млн снижена минеральная плотность костей. Опасность заболевания в том, что переломы тел позвонков и костей, обусловливают высокий уровень нетрудоспособности, включая инвалидность и смертность. Рассказываем, что такое остеопороз и что помогает его лечить. 

По данным, представленным всемирной организацией здравоохранения, около 35% переломов у женщин и 20% у мужчин происходит по причине остеопороза. В пожилом возрасте он является ведущей причиной подобных травм.

Среди всех заболеваний, приводящих к инвалидности и летальному исходу, остеопороз занимает четвертое место (после раковых, сердечно-сосудистых заболеваний и сахарного диабета). О его социальной значимости говорят статистические данные:

• от остеопороза страдают 10% всего населения;
• характерные переломы выявлены у 6% людей;
• ежегодно регистрируется 3 миллиона компрессионных переломов тел позвонков, в том числе 2 миллиона у женщин и 1 – у мужчин;
• среди людей старше 50 лет заболеваемость остеопорозом составляет 28%;
• ежеминутно в России регистрируется 17 переломов костей нижних конечностей, 5 переломов тел позвонков, каждые 5 минут — шейки бедра.

Далее более подробно о том, что это такое и как лечить остеопороз.

Что такое остеопороз?

Остеопороз (лат. osteoporosis) – заболевание, которое проявляется сниженной пластичностью и прочностью костей.

В основе его лежит преобладание процессов разрушения над образованием костной ткани.

Остеохондроз развивается вследствие нарушения минерального обмена: кальция, фосфора и витамина D.

Механизм зависит от фактора, вызвавшего патологию, но для всех форм заболевания характерно последовательное течение следующих процессов:

• вследствие нарушения баланса между образованием и разрушением, замедляется образование костной ткани в период роста и ее обновления;
• снижается масса костной ткани;
• уменьшается прочность кости.

Классификация

По причинному фактору остеохондроз подразделяют на два типа:

Первичный остеохондроз:

1. Тип 1 (также называемый постменопаузальным) – самый распространенный. Страдают от этого типа остеохондроза преимущественно женщины через 15-20 лет после наступления менопаузы. В основе его развития лежит недостаток эстрогена, у мужчин данная патология провоцируется дефицитом тестостерона.
2. Тип 2 (сенильный) развивается в равной степени у мужчин и женщин, чаще после 70 лет.
3. Тип 3 (идиопатический). Причины его неизвестны, страдают молодые люди.

Вторичный остеохондроз (возникает как симптом другой патологии):

• заболевания эндокринной системы (повышение активности паращитовидной железы, недостаточная продукция гормонов щитовидной железы, диабет, гиперфункция надпочечников);
• аутоиммунные болезни (ревматоидный артрит);
• болезни крови (лейкемия, миеломная болезнь);
• новообразования костей;
• патология почек (почечная недостаточность);
• болезни пищеварительной системы, приводящие к уменьшению усвоения кальция.

Стадии развития

Выделяют 4 стадии развития остеопороза:

1. первая (I​) стадия не имеет симптомов, отмечается постепенное уменьшение плотности костей;
2. вторая (II) стадия: костная ткань становится тоньше, но целостность пока не нарушена;
3. третья (I​I​​I) стадия: болезнь поражает несколько отделов позвоночного столба, плотность костной ткани еще больше снижена, изменена форма позвонков;
4. четвертая (IV​) стадия: меняется форма костей, рентгенологически обнаруживаются очаги просветления.

Причины развития остеопороза

Остеопороз – полиэтиологическая патология. Причин возникновения и развития этого заболевания – множество.

Среди них можно выделить следующие:

• дефицит кальция в употребляемой пище;
• нарушение усваивания минералов в кишечнике;
• малая физическая активность;
• нарушение гормонального баланса;
• патология крови;
• аутоиммунные заболевания (волчанка, аутоиммунный тиреоидит);
• нарушение работы почек;
• сахарный диабет;
• поражения пищеварительного тракта;
• злоупотребление кофе, алкогольными и газированными напитками;
• табакокурение;
• длительный прием медицинских препаратов:
  • глюкокортикостероидов;
  • гормонов щитовидной железы;
  • препаратов, снижающих свертываемость крови;
  • средств против судорог;
  • лития;
  • цитостатических препаратов;
  • тетрациклинов;
  • агонистов и антагонистов гонадотропина.

Факторы риска провоцирующие развитие остеопороза

Факторы риска увеличивают возможность формирования остеопороза, среди них:

• принадлежность к европеоидной и монголоидной расе;
• наследственность — наличие подобной патологии у ближайших родственников;
• возраст старше 50 лет;
• женский пол;
• низкий вес (до 56 килограмм женщины, до 70 кг мужчины при условии среднего роста);
• высокий рост (женщины выше 172 сантиметров, мужчины выше 183 сантиметров);

Симптомы остеопороза

Вследствие постепенного снижения плотности костной ткани, остеопороз долгие годы остается незамеченным. Основные признаки остеопороза проявляются, когда костная ткань уже значительно истончена.

Общие признаки остеопороза:

• боли, локализующиеся в костях;
• быстрая утомляемость;
• ранняя седина;
• образование налета на зубах;
• пародонтоз;
• тахикардия сердца;
• патологические переломы (главный признак остеохондроза).

Патологический перелом возможен при минимальной или нормальной нагрузке, возникает вследствие неловкого движения, слабого удара, во время ходьбы, при кашле или чихании.

Признаки остеопороза верхних и нижних конечностей

• тупые боли в костях;
• судороги мышц;
• расслоение ногтей;
• деформируются кости нижних конечностей;
• патологические переломы.

Перелом шейки бедра – характерный симптом остеопороза. Подвергаются ему, как правило, женщины 65-80 лет.

Симптомы остеопороза шейки бедра

• длительные боли в области паха;
• укорочение ноги до 4 сантиметров;
• стопа на пораженной стороне повернута наружу (заметно, когда пациент лежит на спине).

Симптомы остеопороз позвоночника

• боли в поясничном и грудном отделах позвоночника. Боль утихает после сна или отдыха в горизонтальном положении. Симптомы угасают через 9 месяцев после травмы. Временные периоды между переломами составляют от нескольких дней до нескольких лет.
• напряженность спинных мышц;
• асимметричные складки на боках живота;
• сутулость вследствие изменения формы тел позвонков;
• уменьшение роста (более 1 сантиметра в год);
• ограничение подвижности позвоночного столба.

Признаки остеопороза суставов

Наиболее часто остеопорозу подвергаются плечевые, лучезапястные, межпозвоночные, тазобедренные и коленные суставы:

• болезненность в суставах;
• отечность;
• изменение формы;
• хруст;
• ограничение подвижности.

Диагностика

Перед тем, как назначить инструментальные исследования и анализы, врач опрашивает и осматривает больного. Опрос позволяет выявить присутствие факторов риска развития патологии, наличие травм в анамнезе. Во время осмотра оценивается состояние позвоночника, измеряется рост, отмечается при наличии деформация конечностей.

Для уточнения диагноза применяются инструментальные и лабораторные анализы.

Инструментальные методы исследования

Обычно больной обращается к специалисту с переломом, но обнаружить заболевание можно и до нарушения целостности кости.

• Рентгенография позволяет обнаружить перелом, признаки остеопороза выявляется только когда плотность костной ткани стала меньше на 20%. При помощи этого метода можно диагностировать поражение костей конечностей, тел позвонков, таза и черепа.
• Остеоденситометрия оценивает плотность костной ткани.
• Рентгеновская абсорбциометрия позволяет определить не только плотность, но и насыщенность минералами путем облучения более низкими дозами, чем при рентгенографии. Проводится лицам с риском остеопороза.
• Периферическая денситометрия показывает состояние мелких костей. Этот метод используется для выявления болезни и оценки эффективности проведенного лечения.
• Компьютерная и магнитно-резонансная томография отображает состояние кости.

Инструментальные методы исследования позволяют подтвердить наличие остеопороза и тяжесть течения, но для установления причины применяют лабораторные методы.

Лабораторные исследования

• Определение уровня общего кальция в крови (нормальные значения 2,2-2,65 ммоль/л).
• Неорганический фосфор (нормальными считаются значения 0,85-1,45 мкмоль/л).
• Паратгормон регулирует минеральный обмен (нормальные значения 0,7-5,6 пмоль/мл).
• Дезоксипиридинолин отражает процессы разрушения костной ткани, обнаруживается в моче (нормальные значения для мужчин– 2,3-5,4 нмоль/мл, для женщин 3,0-7,4 нмоль/мл).

Лечение

Лечение остеопороза – сложный процесс, в нем участвуют иммунологи, эндокринологии, ревматологи, неврологи и другие специалисты. При постановке диагноза «остеопороз» лечение направлено на уменьшение потери костной массы и активацию процесса ее восстановления.

Медикаментозная терапия

Для терапии этого заболевания используются препараты нескольких лекарственных групп:

• Оказывающие действие на обмен веществ:
  • основная терапия – препараты кальция и витамина Д;
  • флавоновые соединения (Остеозин);
  • оссеино-гидроксиапатитный комплекс тормозит дегенерацию костной ткани и активизирует образование новой;
• Угнетающие деструкцию костной ткани:
  • эстрогены применяются в качестве заместительной терапии (ралооксифен);
  • препараты Кальцитонина стимулируют усвоение кальция из крови;
  • биофосфонаты угнетают резорбцию (разрушение) костей (Этидронат, Памидронат, Алендронат);
  • препараты стронция действуют так же, как препараты кальция;
• Стимулирующие образование костной ткани:
  • паратиреоидный гормон (Терипаратид);
  • соли фтора (рекомендованы при сенильном остеопорозе);
  • соматотропный гормон.

Лечебная физкультура

Ходьба или физические упражнения, которые дают нагрузку, способствуют укреплению костной ткани. Выполнение их регулярно, наряду с другими методами терапии остеохондроза, позволяет остановить прогрессирование болезни. Постепенно организм привыкает к нагрузкам, поэтому комплексы упражнений необходимо периодически менять.

Методы народной медицины

Некоторые виды целебных растений применялись для лечения остеопороза костей еще с древних времен. При использовании отваров и настоев восстанавливается гормональный баланс и улучшается всасывания минералов.

• Мумие нужно принимать по одному шарику за 15 минут до еды, курс лечения составляет 20 дней.
• Скорлупу яиц прокалить в духовом шкафу в течение 30 минут, перетереть до состояния, порошка 150 грамм смешать с 150 граммами прополиса и 75 граммами меда. Принимать 2 месяца по 2 чайных ложки три раза в день.
• Одну столовую ложку измельченного корня солодки залить 2 стаканами кипятка, оставить на полтора часа, процедить, принимать по полстакана 4 раза в день до еды.
• Промыть 2 луковицы, нарезать, обжарить на растительном масле, добавить 1 литр кипятка, томить 15 минут на слабом огне, оставить на 30 минут. Принимать следует до еды три раза в день в течение месяца.
• По 20 грамм зелени укропа и петрушки залить 500 миллилитрами кипятка, оставить на полчаса, отжать, пить в течение 6 месяцев по 100 миллилитров 3 раза в день.
• Настоять 1 столовую ложку травы одуванчика в 200 миллилитрах кипятка в течение 30 минут. Стакан распределить на три приема, продолжительность лечения 3-6 месяцев.

Диета

Пациенты с установленным диагнозом, либо находящиеся в группе риска, должны придерживаться специальной диеты.

Основная задача лечебно-профилактического питания при этом заболевании костей — обеспечение поступления необходимого количества минералов и витамина D.

Рекомендуется исключить следующие продукты из повседневного рациона: кофе, чай, шоколад, сладости, жирные продукты, такие как масло, маргарин, майонез, алкогольные напитки, ржаной хлеб, картофель, ограничивается употребление мяса.

Употребление следующих продуктов обязательно:

• источники кальция: молочные продукты, яйца, орехи, овощи зеленого цвета;
• витамина D: сметана, яйца, растительные масла, рыба;
• витамина A: листовой салат, тыква, печень, фрукты;
• фолиевой кислоты: зеленые овощи;
• цинка: морепродукты, печень;
• марганца: свекла, чеснок;
• магния: зерновые продукты, чернослив;
• фосфора: морепродукты, телятина.

Прогноз

При своевременном обнаружении патологического процесса, его коррекции и исключении фактора риска, прогноз благоприятный.

Однако трудоспособность в некоторых случаях снижается, при необходимости таким пациентам рекомендована работа, не требующую физического труда.

Главное осложнение остеопороза – переломы и их последствия. Иногда их избежать не удается.

Особенно это относится к заболеваниям у людей пожилого возраста. Например, при переломе шейки бедра велик риск инвалидности и летального исхода. Именно поэтому очень важно особое внимание уделить профилактике этого тяжелого заболевания.

Профилактика

Для предупреждения развития остеопороза костей, особенно лицам с наличием одного иди нескольких факторов риска, рекомендовано уделить особое внимание образу жизни.

Мероприятия, направленные на предотвращение развития остеопороза должны начинаться в детстве, тогда кости накопят необходимое количество минеральных веществ.

• Здоровый образ жизни: Исключение алкоголя, курения, ограничение количества кофе и чая служат профилактикой развития остеопороза. Даже малые дозы алкоголя тормозят обновление костной ткани, курение провоцирует спазм капилляров, вследствие этого кальций медленнее усваивается из крови. При чрезмерном употреблении кофе кальций вымывается из костей.
• Физкультура: Физические упражнения полезны для профилактики развития остеопороза. Длительное бездействие мышц провоцирует выход минеральных веществ из костной ткани, снижается плотность костей. Нагрузка должна быть умеренной: йога, фитнес, ходьба. Очень важно, чтобы тренировки были регулярными.
• Питание: Достаточное поступление с продуктами питания кальция, фосфора и магния служит профилактикой остеопороза, а избыточное употребление соли, алкоголя, соблюдение строгой диеты способствуют вымыванию минеральных веществ из костной ткани.
• Солнечные ванны: Ультрафиолетовые лучи, естественные или искусственные (кварцевые лампы) способствуют насыщению организма витамином D. Это способствует минерализации костей.
• Своевременное лечение хронических заболеваний: Многие заболевания пищеварительной системы, почек, гормональные расстройства вызывают нарушение усвоения кальция. Излечение этих болезней уменьшит риск развития остеопороза. При невозможности устранения патологии, необходима коррекция образовавшегося дефицита минеральных веществ. Лекарственная профилактика остеопороза возможна исключительно у лиц из группы риска, препараты назначает лечащий врач.

Профилактика остеопороза необходима всем без исключения, особенно это относится к лицам, находящимся в зоне риска. Им, помимо профилактики, необходим постоянный врачебный контроль, который позволит выявить заболевание на начальном этапе и предотвратить его прогрессирование.

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