Introduction: The clinical significance of low to low-normal testosterone (T) levels in men remains debated.
Aim: To analyze the effects of raising serum T on lean body mass (LBM), fat mass (FM), total body mass, and health-related quality-of-life (HRQoL).
Methods: Randomized, double-blind, placebo-controlled study. Men, aged 50-80 years, with serum total T<15 nmol/L and bioavailable T < 6.68 nmol/L, and a Aging Males' Symptoms (AMS) total score >36, received 6 months treatment with transdermal 1% T gel (5-7.5 mg/day; n =183) or placebo gel (n =179), followed by 12 months open-label with T in all.
Results: After 6 months, LBM increased in T- treated patients by 1.28 ± 0.15 kg (mean ± SE) and FM decreased by 1.16 ± 0.16 kg, with minor changes with placebo (LBM +0.02 ± 0.10 kg and FM -0.14 ± 0.12 kg; all p < 0.001, T group vs. placebo). Changes were largely similar across subgroups of age, baseline total testosterone, and baseline BMI. Total HRQoL improved compared with placebo (p < 0.05, T group vs. placebo).
Conclusions: Six months 1% T gel improved body composition and HRQoL in symptomatic men with low to low-normal T, with further improvements over the following 12 months.