A LONGITUDINAL EVALUATION OF BONE-MINERAL DENSITY IN ADULT MEN WITH HISTORIES OF DELAYED PUBERTY

We have previously demonstrated that men with histories of constitutio nally delayed puberty have significantly lower spinal and radial bone mineral density than normal men. Because these men were in their mid-t wenties, it is possible that bone density was decreased because bone d evelopment was still incomplete. In addition, there is no information on the bone density of the proximal femur, the most important clinical site for osteoporotic fractures, in men with histories of delayed pub erty. To address these issues, we performed repeat measurements of rad ial and spinal bone mineral density 2 yr after the initial evaluations in 18 men with histories of delayed puberty. Bone mineral density of the femoral neck was also measured at the time of follow-up evaluation s. The mean radial bone mineral density at the time of the repeat eval uations was similar to the mean value from the initial evaluations (0. 74 +/- 0.08 vs. 0.74 +/- 0.07 g/cm(2)) and the mean change was 0.00 +/ - 0.04 g/cm(2). Similarly, the mean spinal bone mineral density at the time of the repeat evaluations was similar to the mean value from the initial evaluations (1.02 +/- 0.10 vs. 1.01 +/- 0.10 g/cm(2)) and the mean change was -0.01 +/- 0.04 g/cm(2). Bone mineral density of the f emoral neck was significantly lower in the men with histories of delay ed puberty than in normal men (0.88 +/- 0.11 vs. 0.98 +/- 0.14 g/cm(2) ; P < 0.02). These data indicate that bone accretion is complete by th e mid-twenties in men with histories of constitutionally delayed puber ty and that their bone mineral density does not improve with time. In addition, these men have decreased bone density of the femoral neck, w hich might increase their risk for hip fractures when they are older.