Testosterone therapy effects adipose distribution in older females post hip-fracture: The STEP-HI study

Background: With aging and injury, females experience ectopic redistribution of appendicular adipose tissue (AAT) into the visceral compartment, where adipose tissue (VAT) becomes highly inflammatory and increases risk of reinjury and chronic illness. Therefore, strategies that can disrupt this unhealthy adipose redistribution after hip fracture injury are of great interest. We examined the effects of testosterone therapy on total adipose tissue (TAT) and adipose distribution in older females recovering from hip fracture. Methods: This was a sub-analysis of the STEP-HI study, a multi-site randomized clinical trial in which older females recovering from hip fracture were assigned to a 6-month exercise intervention combined with either topical testosterone gel (EX + T, n = 35, age = 79 ± 9 years) or placebo gel (EX + P, n = 31, age = 76 ± 7 years). Changes in TAT, AAT, and VAT mass and percentage of TAT in each region (%AAT and %VAT) were measured using dual x-ray absorptiometry, and changes over the 6-month intervention were compared between groups. Results: Over the intervention, changes were similar in TAT (EX + P: 298 ± 2002 g, EX + T: 419 ± 2086 g, p = 0.810), AAT (EX + P: 52 ± 1007 g, EX + T: 39 ± 1078 g, p = 0.810), %AAT (EX + P: 0.42 ± 1.40% of TAT, EX + T: 0.52 ± 1.67% of TAT, p = 0.792) and VAT (EX + P: 45 ± 232 g; EX + T: -44 ± 151 g; p = 0.073). However, relative changes in %VAT from pre-intervention (EX + P: Δ3.51 ± 18.42%; EX + T: -Δ10.57 ± 17.13%; p = 0.004) marked favorable effects of testosterone on relative visceral adiposity. Conclusion: While testosterone did not decrease overall adipose stores compared to exercise alone in older females recovering from hip fracture, it did promote a healthy pattern of adipose distribution away from the viscera. Clinical trial #: NCT02938923.