Giới thiệu
Osteoporosis_Disease Background
Osteoporosis is a progressive, systemic skeletal disease characterized by decreased bone mass and microarchitectural deterioration of bone tissue leading to increased bone fragility and susceptibility to fractures. The bone strength, reflecting both the density and quality of the bone, is compromised, thus increasing fracture risk. Fractures commonly occur in the hip, spine, and wrist, with the hip fractures having a high morbidity.
Dịch tễ học
Osteoporosis imposes a significant worldwide healthcare burden. Data from 2019 reveals that approximately 178 million new fractures occurred globally, marking a substantial 33.4% rise in cases compared to 1990. In women, the prevalence of osteoporosis is significantly lower in premenopausal populations than in postmenopausal individuals. Osteoporosis is underdiagnosed in men because of inconsistent clinical screening and failure to recognize the risk in male patients.
Osteoporosis occurs more frequently among individuals of European and Asian descent. Though osteoporosis in Asia is very much underdiagnosed and undertreated, it is projected that by 2050, >50% of osteoporotic hip fractures will happen in Asia. In most developing Asian countries, dual-energy X-ray absorptiometry (DXA) is expensive and is widely unavailable, particularly in the rural areas. Calcium intake in almost all Asian countries is below the FAO/WHO recommendations of 1-1.3 g/day. Studies done in both sexes and all age groups in different Southeast Asian countries demonstrated widespread incidence of vitamin D deficiency or insufficiency.
Sinh lý bệnh
Osteoporosis is a complex condition driven by multiple interacting causes. An adult's total bone mass depends on two key phases: How much peak bone density is built during adolescence, and how much bone is progressively lost after reaching maturity. Over time, the body's natural bone remodeling cycle can shift due to normal aging or underlying health issues. Disruption in this cycle can impair both bone density and mineral homeostasis, ultimately giving rise to osteoporosis. This process accelerates during menopause, where a sudden drop in estrogen levels rapidly triggers bone loss and serves as a primary driver of osteoporosis. Osteoporosis in men involves an imbalance between bone resorption by osteoclasts and bone formation by osteoblasts, driven by age-related hormonal factors, and secondary medical causes.
Yếu tố nguy cơ
Risk Factors for Fracture and Osteoporosis
Postmenopausal women must be evaluated for the risk of osteoporosis. The more risk factors that are present, the greater the risk of fracture.
Non-Modifiable Risk Factors
Non-modifiable risk factors for fracture and osteoporosis include a previous history of fracture as an adult, a history of osteoporotic hip fracture in a first-degree relative, advanced age, poor health or frailty, ethnic group, early natural or surgical menopause before 45 years or prolonged premenopausal amenorrhea >1 year, and genetics and genetic diseases (eg cystic fibrosis, osteogenesis imperfecta, Ehlers-Danlos, hemochromatosis, Marfan syndrome, thalassemia, and hypophosphatasia).
Modifiable Risk Factors
Modifiable risk factors for fracture and osteoporosis include recurrent falls; decreased body weight (<57.6 kg [<127 lb] or body mass index [BMI] <19 kg/m2); impaired vision; medical conditions (eg rheumatoid arthritis, celiac disease, estrogen deficiency, vitamin D deficiency due to lack of sunlight exposure or low intake, thyrotoxicosis, or prolonged Levothyroxine intake, multiple myeloma, bronchial asthma, chronic kidney disease, chronic liver disease, diabetes, epilepsy, human immunodeficiency virus [HIV], hyperparathyroidism, inflammatory bowel disease, malabsorption, neurological disease [eg Alzheimer’s disease, multiple sclerosis, Parkinson’s disease, stroke], systemic lupus erythematosus); cigarette smoking; excessive alcohol and caffeine intake (≥3 drinks/day); low calcium intake, excessive salt, and vitamin A intake; oral glucocorticoid use ≥5 mg/day of Prednisone for ≥3 months; medications (eg anticoagulants, antidepressants, anti-epileptic agents, aromatase inhibitors, gonadotropin-releasing hormone [GnRH] agonists for prostate cancer, Methotrexate, proton pump inhibitors [PPIs], thyroid hormones, thiazolidinediones) and sedentary lifestyle (lack of physical activity, immobilization).
Phân loại
Primary Osteoporosis
Primary osteoporosis refers to bone loss that happens after menopause and with aging.
Secondary Osteoporosis
Secondary osteoporosis is bone loss resulting from diseases (eg endocrine disorders [diabetes, thyroid, and parathyroid disease], gastrointestinal disease) or medications (eg glucocorticoids) or idiopathic.
Glucocorticoid-Induced Osteoporosis (GIOP)
When on oral glucocorticoid therapy, bone loss occurs in the first 6-12 months and fracture risk increases within 3-6 months of initiating glucocorticoids. Intake of ≥5 mg daily of Prednisolone or its equivalent for ≥3 months is associated with osteoporosis. A similar risk is also shown with a higher glucocorticoid dose taken for a shorter period of time. Strong glucocorticoids inhaled for 7 years are associated with significant bone loss. Initial clinical fracture risk assessment is recommended in adults on ≥2.5 mg/day of glucocorticoids for >3 months who have never had a fracture risk assessment or received osteoporosis therapy.
Factors Associated with Steroid-Related Fractures
Factors associated with steroid-related fractures include low bone density; cumulative steroid dose; age >65 years; BMI ≤20 kg/m2 or significant weight loss; smoking and excessive alcohol use; and diseases associated with low bone density (eg rheumatoid arthritis, inflammatory bowel disease, thyroid disease, hyperparathyroidism, chronic liver disease), sex hormone deficiency; family history of osteoporosis, parental history of hip fracture; and history of height loss, fall, or fracture and immobilization.
Indications for Bone Mineral Density (BMD) Measurement
Bone mineral density (BMD) testing with vertebral fracture assessment or spinal X-ray is recommended after starting glucocorticoid therapy and every 1-2 years thereafter while on glucocorticoid therapy. BMD testing within 6 months of starting glucocorticoid therapy is performed in: Adults <40 years old with a history of osteoporotic fracture OR other significant osteoporosis risk factors and adults ≥40 years old with Fracture Risk Assessment Model (FRAX™) with glucocorticoid dose correction. The risk generated with FRAX™ is increased by 1.15 for major osteoporotic fracture and 1.2 for hip fracture if glucocorticoid therapy is >7.5 mg/day.
| CATEGORIES OF FRACTURE RISK IN GLUCOCORTICOID-TREATED PATIENTS* | |||
| Fracture Risk | Adults <40 Years Old | Adults ≥40 Years Old | |
| FRAX™** 10-year Risk of Major Osteoporotic Fracture | FRAX™** 10-year Risk of Hip Fracture | ||
| Low | No risk factors other than glucocorticoid therapy | <10% | ≤1% |
| Hip or spine BMD T-score >-1.0 | |||
| Moderate | Hip or spine BMD Z-score < -3 or rapid bone loss at a rate of ≥10% at the hip or spine in over 1-2 years and continuing glucocorticoid therapy at ≥7.5 mg/day for ≥6 months | ≥10% and <20% | >1% and <3% |
| or Hip or spine BMD T-score between -1.0 and -2.4 | |||
| High | ≥20% and <30% | ≥3% and <4.5% | |
| or Hip or spine BMD T-score between ≤-2.5 and >-3.5 | |||
| Very high | Previous osteoporotic fracture/s or glucocorticoid therapy ≥30 mg/day or cumulative glucocorticoid doses ≥5 g/year | ≥30% |
≥4.5% |
| or Previous osteoporotic fracture/s | |||
| or Hip or spine BMD T-score ≤-3.5 | |||
| or Glucocorticoid therapy ≥30 mg/day or cumulative glucocorticoid doses ≥5 g/year | |||
| *For patients not yet receiving treatment for osteoporosis **With glucocorticoid dose correction Reference: 2022 American College of Rheumatology guideline for the prevention and treatment of glucocorticoid-induced osteoporosis (GIOP) guideline summary. https:/www.rheumatology.org. |
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Using the FRAX™ score to categorize patients' risk, treatment is recommended for postmenopausal women with: Low risk of major osteoporotic fracture (<10%) and intake of ≥7.5 mg daily of Prednisolone or its equivalent for >3 months; moderate risk of major osteoporotic fracture (10-19%) and intake of glucocorticoid at any dose for >3 months; and high risk of major osteoporotic fracture (≥20%) and intake of glucocorticoid at any dose for any length of time.