Aim: To evaluate the effectiveness of testosterone therapy (TT) on a range of sexual function domains in men with type 2 diabetes.
Method: Electronic databases were searched for studies investigating the effect of TT on sexual function in men with type 2 diabetes. All randomised control trials (RCTs) were considered for inclusion if they compared the efficacy of TT with placebo and reported sexual function outcomes. Statistical analysis was performed using a random effects model and heterogeneity expressed as the I2 statistic.
Results: A total of 611 articles were screened. Six RCTs inclusive of 587 men with type 2 diabetes were eligible for inclusion. The pooled data suggested that TT improves sexual desire (random-effects pooled effect size, 0.314; 95% confidence interval [CI], 0.082–0.546) and erectile function (random-effects pooled effect size, 0.203; 95% confidence interval [CI], 0.007–0.399) when compared with control group. TT had no significant effect on constitutional symptoms or other sexual domains compared with control groups. No previous studies have investigated the incidence of prostate cancer, fertility and cardiovascular disease following TT in men with type 2 diabetes.
Conclusion: TT may moderately improve sexual desire and erectile function in men with type 2 diabetes; however, available data are limited, and the long-term risks of TT are not known in this specific patient group. We conclude that TT is a potential treatment for men with type 2 diabetes non-responsive to phosphodiesterase-5 inhibitors. TT could be considered for men with type 2 diabetes when potential risks and benefits of therapy are carefully considered, and other therapeutic options are unsuitable.

Testosterone replacement therapy for sexual dysfunction in men with type 2 diabetic: a meta-analysis of RCT