Epidemiology of osteoporosis. Implications for drug therapy.

Osteoporosis represents a major health problem. Fractures secondary to decreased bone mass and disrupted bone structure vastly increase morbidity in postmenopausal women, and morbidity as well as mortality in elderly people of either sex. Prophylaxis is possible, and indeed appears to be vital to ensure a high peak bone mass. Peak bone mass is reached during the second or third decade of life, i.e. 20 to 50 years before the appearance of osteoporotic fractures. Exercise and a sufficient calcium intake are possible measures in the early years. During menopause, estrogen replacement therapy will delay the accelerated bone loss and, most likely, also osteoporotic fractures. In established osteoporosis, a number of well documented therapies are now available. Depending on the age of the patient, bisphosphonates, calcitriol or other vitamin D preparations, calcium and calcitonin may be employed. This article reviews the epidemiology of osteoporotic fractures with special reference to the therapeutic implications.