[Epidemiology of osteoporosis].

Osteoporosis leads to fragility fractures. Fracture incidence increases after the menopause among women and with age in both genders. More than 40 % of women will sustain at least one fragility fracture after the age of 50. Many risk factors have been described, including age, familial history of fracture, low bone mineral density, personal history of fracture, smoking and low body mass index. Fracture incidence is increasing worldwide, owing to population aging. Hip and vertebral fractures are associated with increased mortality and morbidity. Costs related to fragility fractures represent a significant burden for health care systems.