Have rates of erectile dysfunction improved within the past 17years after radical prostatectomy? A systematic analysis of the control arms of prospective randomized trials on penile rehabilitation

Based on case series, potency rates after radical prostatectomy (RPE) differ substantially and - furthermore - it remains unclear whether they have improved in more recent surgical series. The purpose of this study was to investigate whether potency rates after RPE have improved over the years. A systematic analysis of the control arms of all randomized controlled trials (RCT; n=11) on penile rehabilitation after RPE was carried out. In total, 2009 patients were included in these RCTs, 685 thereof in the respective control arms, who were either observed or received placebo. Assessment of erectile function in these studies was carried out by the Sexual Encounter Profile (SEP) or the International Index of Erectile Function (IIEF). Eight trials used SEP3 as study endpoint. The rate of positive response to SEP3 (=erectile function sufficient for successful intercourse) in the control arms was 20% in 1997 (year of publication), 10% in 2003, 19% in 2004, 25% in 2008, 21% in 2010, 67% in 2011, 10% in 2013, and 22% in 2014. Eight RCTs assessed the IIEF-EF, yet results were not reported uniformly. In the control arms the IIEF-EF was 9.2 (year of publication 2003), 13.3 (2004), 8.8 (2008), 25% 22.0 (2008), 17.4 (2010), 58% 26.0 (2011), 9.3 (2013), and 11.6 (2014). Limitations of this analysis are a positive selection bias regarding patient recruitment, surgical approach, and the non-uniform inclusion and outcome criteria. This systematic analysis of the control arms of all RCTs on penile rehabilitation after nerve-sparing RPE shows (i) that the rate of undisturbed erectile function is in the range 20-25% in most studies and (ii) that these rates have not substantially improved or changed over the past 17years.