Efficacy of phosphodiesterase type 5 inhibitors in patients with erectile dysfunction after nerve-sparing radical prostatectomy: a systematic review and meta-analysis

Background: Nerve-sparing radical prostatectomy (NSRP) had to be performed because approximately 94% of patients are diagnosed with localized prostate cancer (PCa). Although NSRP is generally done to improve functional outcomes, erectile dysfunction (ED) is one of the most prevailing complications after radical prostatectomy (RP). Phosphodiesterase type 5 inhibitors (PDF,5-1s) are the most well-known treatment agent for postoperative ED. This study aimed to assess the efficacy of PDE5-Is in patients with ED after NSRP. Methods: In this systematic literature review, randomized controlled trials on the efficacy and safety of PDE5-Is in patients who underwent NSRP were searched in MEDLINE, EMBASE, and the Cochrane Controlled Trials Register using the OVID platform. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Cochrane Review Methods. The quality of the evidence of the outcome data was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. Results: A total of 14 trials involving 2,822 patients were included. Significant improvements in the International Index of Erectile Function-Erectile Function (IIEF) domain score [mean difference (MD) =4.93; 95% confidence interval (CI): 4.14-5.71; P<0.00001] and erectile function recovery events [odds ratio (OR) =2.06; 95% CI: 1.45-2.94; P<0.0001] were observed after PDE5-I treatment. A higher positive response to Sexual Encounter Profile (SEP) question 2 (OR =2.27; 95% CI: 1.80-2.86; P<0.00001) and question 3 (OR =2.78; 95% CI: 1.97-3.91; P<0.00001) was also found after PDE5-I treatment. However, the incidence of treatment-emergent adverse events (TEAEs) was higher after PDE5-I treatment than after placebo treatment (OR =2.91; 95% CI: 1.84-4.61). Furthermore, the incidence of headache (OR =3.38; 95% CI: 2.40-4.75) and flushing (OR =9.44; 95% CI: 4.30-20.70) was also significantly higher after PDE5-I treatment (P<0.00001). In terms of the quality of the evidence of the outcome data, inconsistency problems were detected in all outcomes and imprecision problems in most outcomes. Conclusions: PDE5-I treatment was more effective to placebo treatment in patients with ED after NSRP. No clinically serious complications were found in spite of the incidence of TEAEs being higher after PDE5-I treatment.