The epidemiology of hip fractures and methods of prevention.

Hip fractures are common in the elderly, affecting 1 in 4 women by the age of 90 years and 1 in 8 men. These fractures have caused an "epidemic" during the last 20 years because the age specific rate for such fractures has doubled, and there has been a significant increase in the size of the elderly population in Europe. Hip fracture patients occupy a quarter of all orthopedic beds, the treatment is costly and the rehabilitation slow. Fifteen percent die in hospital; 33% are dead by one year. Of survivors only 2/3 return to their own home. There is now a move to prevent such fractures. Hip fractures arise in the elderly for two reasons: deteriorating bone stock and increasing falls. Hip fracture prevention needs to address both issues, but most work has looked at bone stock. Predictions of hip fracture risk even if based on bone density are poor, so preventive measures need to target the whole population. Bone density rises to a peak at 35 to 40 years in both sexes; men have a higher bone density at all times than women. Thereafter there is a steady loss of 1-2% per year. Women have 10 years of accelerated loss after the menopause. Hip fracture prevention starts by ensuring that peak bone mass is reached. This is under genetic influence but may be maximized by adequate dietary calcium and physical activity in adolescence. Smoking, alcohol and steroid use reduce bone density and their use should be moderated. In women amenorrhea reduces bone density. For women, estrogen may stop menopausal loss and maintain bone density for at least 15 years and in retrospective studies can reduce the fracture risk by 50%. Calcitonin may be an alternative. Five years beyond the menopause primary or secondary prevention may be started. Estrogen is still the best therapy but may be less popular because of the return of menstrual periods. Calcitonin or oral calcium supplements may also be of benefit. Drugs in combination may be more effective than alone. Over age 70, when calcium absorption diminishes, vitamin D, calcium and calcitonin may be effective. For men, treatment options are calcium, calcitonin or, later on, vitamin D. The role of exercise in bone density protection is unclear but should be encouraged for general health reasons. Bisphosphonates are new drugs that may be useful. Falls become increasingly common in the elderly such that up to 80% of all 80-year-olds may sustain at least one fall per year.(ABSTRACT TRUNCATED AT 400 WORDS)