[Clinical characteristics of male osteoporosis].

As men are less likely than women to develop osteoporosis, male osteoporosis remains poorly understood. However, elderly men have a clearly reduced bone mineral density and increased risk for fractures. In Japan, one in four patients with osteoporosis is male. Male osteoporosis is associated with not only reduction in androgen, but also estrogen, and differs from postmenopausal osteoporosis in that decreased bone formation is involved and that age-related changes in cortical bone structure and perforation of the trabeculae of cancellous bone are unlikely to occur. The proportion of secondary osteoporosis is higher for men than women;therefore, differential diagnosis is important in the diagnosis of male osteoporosis. In addition, it is recommended that bone mineral density be measured at the femoral neck or total hip in men. Men have a worse prognosis following fractures than women, and management of male osteoporosis is highly important for extending healthy life expectancy.