Osteoporosis in Men

ALTHOUGH osteoporosis has long been considered a disease of women, in the earliest reports of the epidemiology of osteoporosis it was apparent that the classical age-related increase in fractures seen in women is evident in men as well. Only in the last few years has it been recognized that the problem of osteoporosis in men represents an important public health issue and that it presents a unique array of scientific challenges and opportunities (1–3). Here we examine the issue of osteoporosis in men and compare its pathophysiology and clinical presentation with parallel processes in women. Women exhibit a dramatic increase in bone mass that begins during adolescence and is almost complete when puberty ends (4). In men, a similar relationship of bone mass accretion to adolescence holds, but the chronological onset of puberty is later in men than women, and the achievement of peak bone mass is also later. As a result of diverging growth trends (primarily during puberty), there are obvious sexual differences in adult skeletal morphology. The development of adult bone mass is dependent upon changes in both density and size, but sexual differences are, for the most part, related to differences in size. Skeletal dimensions in men are larger than those in women. For example, radial width and cortical thickness are considerably larger in men (5), femoral neck cross-sectional area is larger (6), and vertebral body cross-sectional area is larger (7). As a result, total body bone mineral is greater in men (3100-3500 g in young men vs. 2300–2700 g in young women) (8, 9). Although maximal adult mineral density is also frequently reported to be greater in men, this is primarily an artifact of the methods used for its measurement.