Effects of Testosterone on Muscle Strength, Physical Function, Body Composition, and Quality of Life in Intermediate-Frail and Frail Elderly Men: A Randomized, Double-Blind, Placebo-Controlled Study
Context: Physical frailty is associated with reduced muscle strength, impaired physical function, and quality of life. Testosterone (T) increases muscle mass and strength in hypogonadal patients. It is unclear whether T has similar effects in intermediate-frail and frail elderly men with low to borderline-low T. Objective: Our objective was to determine the effects of 6 months T treatment in intermediate-frail and frail elderly men, on muscle mass and strength, physical function, and quality of life. Design and Setting: We conducted a randomized, double-blind, placebo-controlled, parallel-group, single-center study. Participants: Participants were community-dwelling intermediate-frail and frail elderly men at least 65 yr of age with a total T at or below 12 nmol/liter or free T at or below 250 pmol/liter. Methods: Two hundred seventy-four participants were randomized to transdermal T (50 mg/d) or placebo gel for 6 months. Outcome measures included muscle strength, lean and fat mass, physical function, and self-reported quality of life. Results: Isometric knee extension peak torque improved in the T group (vs. placebo at 6 months), adjusted difference was 8.6 (95% confidence interval, 1.3–16.0; P = 0.02) Newton-meters. Lean body mass increased and fat mass decreased significantly in the T group by 1.08 ± 1.8 and 0.9 ± 1.6 kg, respectively. Physical function improved among older and frailer men. Somatic and sexual symptom scores decreased with T treatment; adjusted difference was −1.2 (−2.4 to −0.04) and −1.3 (−2.5 to −0.2), respectively. Conclusions: T treatment in intermediate-frail and frail elderly men with low to borderline-low T for 6 months may prevent age-associated loss of lower limb muscle strength and improve body composition, quality of life, and physical function. Further investigations are warranted to extend these results.