Do the Effects of Testosterone on Muscle Strength, Physical Function, Body Composition, And Quality of Life Persist Six Months after Treatment in Intermediate-Frail and Frail Elderly Men?

Context: Short-term testosterone (T) treatment in frail elderly men improves muscle mass and strength. It is unclear whether these effects can be maintained post treatment. Objective: To assess the durability of androgen effects in frail men. Design and Setting: Single center, randomized, double-blind, placebo-controlled trial to investigate the effects of 6 months T (25-75 mg daily) on muscle strength, body composition, physical function, and quality of life (QoL). Participants were assessed at the end of treatment (6 months) and 6 months after treatment cessation (12 months). Participants: 274 intermediate-frail and frail elderly men aged 65-90 years with low T levels. Results: Mean T increased from 11.1 (3.1) nmol/liter at baseline to 18.4 (3.5) nmol/liter at 6 months, then declined to 10.5 (3.7) nmol/L at 12 months, in the T-treated group. Isometric knee extension peak torque increased in the T-treated group compared with placebo to give an adjusted mean difference (95% CI) between groups of 8.1 (-0.2 to 16.5) Nm at 6 months. Lean mass increased in the T-treated group giving a difference between groups of 1.2 (0.8 to 1.7) kg at 6 months. Somatic and sexual symptoms improved during treatment. None of these differences between groups remained at 12 months. Prostate specific antigen (PSA) levels and haematocrit increased slightly during treatment but returned to baseline by 12 months. Conclusion: The effects of 6-month T treatment on muscle strength, lean mass, and QoL in frail men are not maintained at 6 months post treatment. (J Clin Endocrinol Metab 96: 454-458, 2011)