Endothelial Dysfunction in Patients With Erectile Dysfunction: A Double-Blind, Randomized-Control Trial Using Tadalafil

Abstract

Objective: To assess whether tadalafil improves endothelial dysfunction(EnD) in a placebo-controlled randomized-control trial. Methods: Erectile dysfunction and EnD were assessed by the International Index of Erectile Function (IIEF-5) and flow-mediated dilation (FMD) of the brachial artery respectively, at baseline and 4 weeks by blinded observer. Patients with FMD of < 15% were randomized in 1:1 ratio to receive either placebo or tadalafil. Both placebo and tadalafil in similar-appearing capsules but coded separately, were dispensed by a blinded co-investigator. Compliance and drug-related events were recorded. The randomization codes were then decoded and appropriate statistical tests applied. Results: 89 patients were randomized and 82 completed the study. Both groups were comparable. Posttreatment, there were significant improvements in IIEF-5 score (pre- vs posttreatment; tadalafil: 11.432 vs 15.937, P < .001 and placebo 11.232 vs 14.935, P < .00) and FMD% pre- vs posttreatment; tadalafil: 11.222 vs 13.827, P < .001 and placebo: 11.617 vs 14.027, P < .001). Intergroup comparison did not show any significant difference in IIEF scores (mean change in tadalafil vs placebo group: 3.719 vs 4.433, P = .223) and FMD% (mean change tadalafil vs placebo group: 2.426 and 2.829, P = .528). The adverse events were significantly more in the tadalafil group (tadalafil vs placebo 14 adverse reactions [ADR] vs 5 ADR, P < .001). Conclusion: The response of low-dose tadalafil on IIEF and FMD is largely similar to placebo; however, the utility of FMD% in young patients and placebo effect needs to be studied further.Pattanaik S, Kaundal P, Mavuduru RS, et al. Endothelial Dysfunction in Patients With Erectile Dysfunction: A Double-Blind, Randomized-Control Trial Using Tadalafil. Sex Med 2019;7:41–47. Key Words: Endothelial Dysfunction, Erectile Dysfunction, Flow-Mediated Dilation of Brachial Artery (FMD), Tadalafil