Obese men commonly have reductions in circulating testosterone and report symptoms consistent with androgen deficiency. We hypothesized that testosterone treatment improves constitutional and sexual symptoms over and above the effects of weight loss alone.
We conducted a pre-specified analysis of a randomized double-blind, placebo-controlled trial at a tertiary referral centre. 100 obese men (BMI>30 kg/m(2)) with a repeated total testosterone level <12 nmol/l and a median age of 53 years (interquartile range 47-60) receiving 10 weeks of a very low energy diet (VLED) followed by 46 weeks of weight maintenance were randomly assigned at baseline to 56 weeks of intramuscular testosterone undecanoate (n=49, cases) or matching placebo (n=51, controls). Pre-specified outcomes were the between-group differences in Aging Male Symptoms scale (AMS) and international index of erectile function (IIEF-5) questionnaires.
Eighty-two men completed the study. At study end, cases showed significant symptomatic improvement in AMS score, compared to controls, and improvement was more marked in men with more severe baseline symptoms (mean adjusted difference (MAD) per unit of change in AMS score -0.34 [95%CI -0.65, -0.02], P=0.04). This corresponds to improvements of 11 and 20% from baseline scores of 40 and 60, respectively, with higher scores denoting more severe symptoms. Men with erectile dysfunction (IIEF-5<20) had improved erectile function with testosterone treatment. Cases and controls lost the same weight after VLED (testosterone -12.0 kg; placebo -13.5 kg, P=0.40) and maintained this at study end (testosterone -11.4 kg; placebo -10.9 kg, P=0.80). The improvement in AMS following VLED was not different between groups (-0.05 [95% CI -0.28, 0.17], P=0.65).
In otherwise healthy obese men with mild to moderate symptoms and modest reductions in testosterone levels, testosterone treatment improved androgen deficiency symptoms over and above the improvement associated with weight loss alone, and more severely symptomatic men achieved a greater benefit.International Journal of Obesity accepted article preview online, 28 December 2016. doi:10.1038/ijo.2016.242.
International journal of obesity (2005). 2016 Dec 28 [Epub ahead of print]
M N T Fui, R Hoermann, L A Prendergast, J D Zajac, M Grossmann
Department of Medicine Austin Health, University of Melbourne, Heidelberg, Australia.