Different testosterone levels are associated with ejaculatory dysfunction

Introduction. The role of testosterone (T) in pathogenesis of ejaculatory symptoms has not been completely clarified. Aim. To evaluate the possible contribution of T and hypogonadism in the control of the ejaculatory reflex, comparing subjects with premature ejaculation (PE) or delayed ejaculation (DE) to those without ejaculatory dysfunction. Methods. A consecutive series of 2,437 (mean age 51.9 +/- 13.0 years) male patients with sexual dysfunction was studied. Main Outcome Measure. Several hormonal and biochemical parameters were studied, along with the structured interview on erectile dysfunction (SIEDY) structured interview. Hypogonadism were defined when total testosterone (TT) was lower than 10.4 nmol/L. Results. Among the patients studied, 714 (25.9%) and 121 (4.4%) reported PE and DE, respectively. In the youngest age band (25-40 years), subjects with PE reported higher TT and free testosterone (FT) levels when compared to the other groups (subjects with DE or those without PE and DE; P < 0.05 for both). Conversely, in the oldest age band (55-70 years), lower TT and FT levels were observed in DE subjects. Accordingly, patients with PE showed the lowest (12%) and subjects with DE the highest (26%) prevalence of hypogonadism. These differences were confirmed even after adjustment for confounders such as age and libido (HR = 0.75 [0.57-0.99] and 1.83 [1.14-3.94] for PE and DE, respectively; both P < 0.05). Conclusions. Our data seem to suggest that T plays a facilitatory role in the control of ejaculatory reflex. Both central and peripheral mechanisms have been advocated to explain this association. Clinical studies are currently in progress to further establish the role of T in the ejaculatory dysfunction, attempting to revert DE by androgen administration.