Effects of testosterone on sexual function in men: results of a meta‐analysis

Abstract

Overall, 656 subjects were evaluated: 284 were randomized to T, 284 to placebo (P) and 88 treated in cross-over. The median study length was 3 months (range 1-36 months). Our meta-analysis showed that in men with an average T level at baseline below 12 nmol/l, T treatment moderately improved the number of nocturnal erections, sexual thoughts and motivation, number of successful intercourses, scores of erectile function and overall sexual satisfaction, whereas T had no effect on erectile function in eugonadal men compared to placebo. Heterogeneity was explored by grouping studies according to the characteristics of the study population. A cut-off value of 10 nmol/l for the mean T of the study population failed to predict the effect of treatment, whereas the presence of risk factors for vasculogenic erectile dysfunction (ED), comorbidities and shorter evaluation periods were associated with greater treatment effects in the studies performed in hypogonadal, but not in eugonadal, men. Meta-regression analysis showed that the effects of T on erectile function, but not libido, were inversely related to the mean baseline T concentration. The meta-analysis of available studies indicates that T treatment might be useful for improving vasculogenic ED in selected subjects with low or low-normal T levels. The evidence for a beneficial effect of T treatment on erectile function should be tempered with the caveats that the effect tends to decline over time, is progressively smaller with increasing baseline T levels, and long-term safety data are not available. The present meta-analysis highlights the need, and pitfalls, for large-scale, long-term, randomized controlled trials to formally investigate the efficacy of T replacement in symptomatic middle-aged and elderly men with reduced T levels and ED.

Testosterone and Erectile Function: From Basic Research to a New Clinical Paradigm for Managing Men with Androgen Insufficiency and Erectile Dysfunction

“…The patient should also meet the definition of ED [4]. [146] determined that exogenous testosterone improved the number of nocturnal erections and successful intercourses, sexual thoughts, scores of erectile function, and overall sexual satisfaction in men with low testosterone, but had no effect on eugonadal men. They concluded that the effect of testosterone tended to decline over time and was progressively smaller with increasing baseline T levels, and that long-term safety data were not available [146].…”

Are declining testosterone levels a major risk factor for ill-health in aging men?

“…[86][87][88] Overviews of randomized controlled clinical trials indicate some benefit of testosterone therapy on sexual health-related outcomes, however further investigation in this area is warranted particularly in older men who are not clearly hypogonadal. 65,[88][89][90] In men with erectile dysfunction, low free testosterone levels correlate with impaired relaxation of cavernous endothelial and corporeal smooth muscle cells to a vasoactive challenge. 91 A direct effect of testosterone is feasible as testosterone modulates expression of endothelial nitric oxide synthase and phosphodiesterase type 5 (PDE5) within penile tissues.…”

A view of geriatrics through hormones. What is the relation between andropause and well-known geriatric syndromes?

“…TRT increases the activity of hepatic lipoprotein lipase inducing a decrease in high density lipoprotein levels [20], especially in patients with higher pretreatment T levels [99]. Intramuscular (IM) T has smaller effects on HDL, probably through higher conversion to E2 counteracting T effects on lipoprotein lipase [100].…”