Osteoporosis: A Review.

IMPORTANCE: Osteoporosis is characterized by low bone mass, increased bone fragility, and increased susceptibility to fracture, which is associated with substantial morbidity, mortality, and economic costs. Worldwide, 1 in 3 women and 1 in 5 men older than 50 years of age experience osteoporotic fractures in their lifetime. OBSERVATIONS: Risk factors for osteoporosis include older age, female sex, prior fractures, prior falls, low body weight, history of hip fracture in a parent, glucocorticoid use, cigarette smoking, excess alcohol consumption, certain comorbidities (eg, inflammatory bowel disease, rheumatoid arthritis, and chronic liver and kidney disease), and low level of bone mineral density (BMD; measured by dual-energy x-ray absorptiometry). The fracture risk assessment algorithm combines these clinical risk factors and BMD measurement to estimate the 10-year absolute fracture risk for hip, spine, shoulder, and forearm fractures. For patients at high risk of fracture, such as those with a T score of -2.5 or less (equivalent to a bone mass that is ≥2.5 SDs below that of young adults) for BMD, history of vertebral or hip fracture, multiple fractures, or high 10-year absolute fracture risk (eg, ≥20%), antiresorptive agents (bisphosphonates or, if contraindicated, denosumab) are recommended to reduce vertebral fractures (risk difference, -52 [95% CI, -95 to -18 per 1000 person-years]) and hip fractures (risk difference, -6 [95% CI, -11 to -1 per 1000 person-years]). Anabolic medications (teriparatide, abaloparatide, and romosozumab) should be considered in very high-risk individuals (eg, recent vertebral fractures, hip fracture with a T score of ≤-2.5 for BMD), followed by an antiresorptive agent. The use of fracture liaison services (comprehensive inpatient or outpatient management program for patients after a fracture) was shown to increase medication initiation and adherence by 38% compared with 17% for patients who did not receive fracture liaison services (risk difference, 20% [95% CI, 16% to 25%]) and these benefits may reduce the rates of subsequent fracture. Patients are recommended to follow appropriate intake of calcium (1000 to 1200 mg) and vitamin D (600 to 800 IU) guidelines and to pursue a regimen of muscle resistance exercises (eg, squats, push-ups) and balance exercises (eg, heel raises, standing on 1 foot). CONCLUSIONS AND RELEVANCE: Osteoporosis is a common condition among older adults that leads to increased susceptibility to fracture, which is associated with substantial morbidity and mortality. Antiresorptive agents such as bisphosphonates or denosumab are recommended for patients at high fracture risk. Anabolic treatment with parathyroid hormone analogs (such as teriparatide and abaloparatide) and sclerostin inhibitors (such as romosozumab) can be considered for very high-risk individuals.