BONE-MINERAL DENSITY AND BODY-COMPOSITION IN CONGENITAL ADRENAL-HYPERPLASIA

The purpose of this study was to assess whether replacement doses of g lucocorticoid hormones administered to patients with congenital adrena l hyperplasia (CAH) cause changes in body composition, including eithe r generalized or regional osteoporosis. In 21 patients with 21-hydroxy lase deficiency we measured height, body mass index, lean mass, fat ma ss, and whole body and regional bone mineral density (BMD). We measure d the same parameters in 21 age- and sex-matched control patients. The CAH group (aged 8-32 yr) showed significantly reduced mean height com pared with both standard data (P = 0.0015) and the control group (P = 0.009). There were no sigificant differences in mean body mass index b etween the CAH group and the standard data (P = 0.13) or the control g roup (P = 0.87). CAH males had significantly higher fat/lean mass rati os than control males (P = 0.005). There were no significant differenc es in whole body mean bone mineral apparent density values between the CAH and control groups (P = 0.39). There were, however, significant d ifferences in whole body BMD z scores between the CAH and control grou ps and the reference data (P = 0.027 and P = 0.004, respectively). No significant differences were observed between the total CAH and contro l groups with respect to spinal bone mineral apparent density; however CAH males had significantly lower mean adjusted spinal BMD than the m ale controls (P = 0.02). We conclude that although replacement therapy with glucocorticoid and mineralocorticoid hormones in our group of CA H patients may not be optimal with regard to longitudinal growth, it i s not deleterious in terms of general bone mineralization. It may decr ease spinal BMD in CAH males. We also conclude that the relevance of H ologic reference data for BMD to an Australian population is uncertain , and there is a need For Australian standard data.