Endocrine Abstracts

Objective: The objective of the study was to assess the effect of intra-muscular testosterone on body composition in men with hypogonadism and poorly controlled type 2 diabetes.

Research design and methods: This is a randomised double-blinded placebo-controlled add-on trial of intramuscular testosterone undecanoate administered every 12 weeks in 65 hypogonadal men with poorly-controlled diabetes. Phase 1 patients were randomly assigned to either treatment or placebo arm for 6 months of TRT. Phase 2 was an open-labelled phase for 6 months and patients on placebo moved on to the treatment group wherein patients in the treatment group continued. Body composition was measured by dual energy X-ray absorptiometry (DEXA scan). Outcomes were assessed at baseline and every 3 months.

Results: Mean age of the cohort was 59 years. Baseline characteristics were comparable between active/placebo groups. Only 48 patients had DEXA scans both at baseline and at 6 months. Limb fat mass and percentage fat significantly correlated strongly and inversely with total testosterone(TT), calculated free testosterone (cFT) and bioavailable testosterone(cBT) and there was no correlation with limb lean mass. There was strong inverse correlation between total fat mass, total fat percentage and truncal fat percentage with TT, cFT and cBT(P<0.05). Truncal fat mass correlated inversely with TT and cBT but did not correlate significantly with cFT. There was no significant correlation between lean mass and TT, cFT or cBT. These correlations remained significant after correcting for age, BMI and SHBG in linear regression model. There was a significant reduction in Left leg fat mass in the active group compared to placebo group. (P=0.03) after 6 months of TRT. There was no significant difference in either the fat mass or lean mass between the active and placebo group elsewhere including truncal area. There were no significant changes in either fat or lean mass before and after 12 months of treatment with testosterone in the active group

Conclusions: Testosterone levels strongly and inversely correlates with fat mass and has no correlation with the lean mass. There was significant reduction in left leg fat mass after 6 months of TRT. There were no significant changes in any other body composition at 6 or 12 months and it suggests that these changes may take more than a year to show positive changes.