Short-term effect of testosterone treatment on reduced bone density in boys with constitutional delay of puberty.

We studied bone mineral content (BMC), bone mineral density (BMD), cortical thickness/total width (CT/TW) ratio and cortical area/total area (CA/TA) ratio in boys with constitutional delay of puberty and the effect of short-term testosterone treatment on bone mass. Seventeen boys (age 13.1-15.8 years) who met the family history and the clinical criteria of constitutional delay of puberty were selected and enrolled in the study. All subjects were eating a diet assuring an adequate intake of calories and calcium. A subset of 8 boys (group A) was treated with testosterone depot (100 mg/month x 6 months) while 9 boys (group B) were not. At inclusion, BMC and BMD were reduced in the patients according to their chronological age (BMC -4.04 +/- 1.34 standard deviation scores [SDS]; BMD -2.95 +/- 0.56 SDS), statural age (BMC -1.75 +/- 0.79 SDS; BMD -1.69 +/- 0.78 SDS), and bone age (BMC -1.80 +/- 0.65 SDS; BMD -1.86 +/- 0.68 SDS). No significant differences between the groups were found (group A: BMC 0.480 +/- 0.57 g/cm, BMD 0.488 +/- 0.037 g/cm2, CT/TW ratio 0.43 +/- 0.4, CA/TA ratio 0.68 +/- 0.04; group B: BMC 0.476 +/- 0.060, p = NS vs. group A; BMD 0.491 +/- 0.036 g/cm2, p = NS vs. group A). At 12 months of follow-up, BMC, BMD, CT/TW ratio, and CA/TA ratio significantly increased in group A (BMC 0.70 +/- 0.13 g/cm, delta +41.1 +/- 28.8%, p < 0.003 vs. 0 month; BMD 0.617 +/- 0.082 g/cm2, delta +26.2 +/- 13.6%, p < 0.005 vs. 0 month; CT/TW ratio 0.52 +/- 0.05, delta +20.59 +/- 10.65%, p < 0.001 vs. 0 month; CA/TA ratio 0.77 +/- 0.05 vs. 0 month; CT/TW ratio 13.60 +/- 6.65%, p < 0.004 vs 0 month), but not in group B (BMC: 0.48 +/- 0.05 g/cm; delta +5.1 7.8%, p = NS vs. 00 month; BMD: 0.492 +/- 0.037 g/cm2; delta +0.54 +/- 8.7%, p = NS vs. 0 month; CT/TW ratio 0.44 +/- 0.04, delta +4.04 +/- 6.75%, p = NS vs. 0 month; CA/TA ratio 0.68 +/- 0.05, delta +2.39 +/- 5.90%, p = NS vs. 0 month). We conclude that boys with constitutional delay of puberty have reduced BMC and BMD. The delay in statural and bone ages did not totally account for the decreased bone mass. Testosterone treatment for 6 months significantly increased BMC, BMD, CT/TW ratio, and CA/TA ratio in these patients, but definitive conclusions on the efficacy of the treatment in improving adult bone mass can be drawn only when our patients reach early childhood.