Male osteoporosis: epidemiology and the pathogenesis of aging bones.

Osteoporosis in men is an overlooked yet increasingly important clinical problem that, historically, has not received the same degree of awareness as with women. Epidemiologic studies demonstrate that male osteoporosis contributes significantly to the burden of osteoporotic fractures, especially among the aging population. In particular, men have increased morbidity and mortality associated with osteoporotic fractures compared with women. Diagnostic challenges of male osteoporosis include lack of consensus about appropriate reference ranges for identifying osteoporosis in men, and the lack of a fracture assessment tool in men necessary to identify those individuals at risk. Compared with women, changes that occur in the aging male skeleton include trabecular thinning, greater endocortical expansion, ongoing periosteal apposition with greater bending strength, and preserved minimum moment of inertia. Overall, men have less microstructural damage with aging and beneficial geometric adaptations that lead to stronger bones, compared with women, and thus their overall lower risk of fractures.