Predictors of Worsening Erectile Function in Men with Functional Erections Early After Radical Prostatectomy

Abstract Background Prior studies suggest that men with good erectile function shortly after radical prostatectomy (RP) can subsequently have worsened erectile function. Aim To determine the prevalence and predictors of early erectile function recovery post-RP and of worsening erectile function after initial erectile function recovery. Methods We retrospectively queried our institutional database. Men who underwent RP during 2008–2017 and who completed the International Index of Erectile Function erectile function domain both pre-RP and serially post-RP, constituted the population. Functional erections were defined as International Index of Erectile Function (IIEF)-6 erectile function domain scores ≥24. We analyzed factors predicting functional erections at 3 months post-RP as well as factors predicting a decrease in functional erections between 3 and 6 months, defined as ≥2-point drop in the erectile function domain. Multivariable logistic regression models were used to identify predictors of early erectile function recovery and also of subsequent decline. Outcomes Erectile function recovery rates at 3 months post-RP and predictive factors; rates of erectile function decline between 3-6 months and associated predictors. Results Eligible patients comprised 1,655 men with median age of 62 (IQR 57, 67) years. Bilateral nerve-sparing (NS) surgery was performed in 71% of men, unilateral NS in 19%, and no NS in 10%. Of this population, 224 men (14%; 95% CI 12%, 15%) had functional erections at 3 months post-RP. On multivariable analysis, significant predictors of early erectile function recovery included: younger age (OR 0.93, P < .001), higher baseline erectile function domain score (OR 1.14, P < .001) and bilateral NS (OR 3.81, P = .002). The presence of diabetes (OR 0.43, P = .028) and a former smoking history (OR 0.63, P = .008; reference group: never smoker) was associated with the erectile dysfunction at 3 months post-RP. Of the men with early functional erections, 41% (95% CI 33%, 48%) had a ≥ 2-point decline in erectile function between 3 and 6 months. No factors were identified as predictors for this decline. Clinical Implications Only a small proportion of men have functional erections at 3 months post-RP and a notable number of them will experience a decline in erectile function between 3 and 6 months. Strengths and Limitations Strengths: large patient population and the use of validated questionnaire. Limitations: single-center retrospective study. Conclusion A minority of men had functional erections 3 months post-RP, about half of whom had a decline in erectile function by month 6. We recommend appropriately counseling post-RP patients on the risk of such a decline in erectile function.