title: A prospective, randomized, placebo-controlled trial of on-Demand vs. nightly sildenafil citrate as assessed by Rigiscan and the international index of erectile function.
abstract: Multiple studies have evaluated the use of PDE5 inhibitors in penile rehabilitation following nerve-sparing prostatectomy. These studies have evaluated the use of various pharmacologic agents as well as various approaches to treatment (on-demand vs. rehabilitative). Most of these studies relied on self-reported outcomes to determine efficacy of the therapy which could allow response bias to affect their results. The aim of this study was to evaluate the effects of nightly sildenafil citrate therapy during penile rehabilitation, using nocturnal penile rigidity (RigiScan(™), Gotop Medical, Inc., St. Paul, MN, USA) in addition to the IIEF-EF. Patients with localized prostate cancer and normal erectile function prior to nsRP were randomized to take either nightly 50 mg sildenafil citrate or placebo starting the night following surgery. Both groups were allowed on-demand sildenafil citrate. Erectile function was evaluated at 2 weeks, 3, 6, 9 and 12 months post-operatively, with a final assessment made at 13 months, following a 1 month drug washout. At all time points, self-reported (IIEF-EF) and objective (RigiScan(™)) measures were obtained and evaluated. About 74 of 97 randomized patients completed the study. On completion, 40% of patients in each group had normal erectile function based on RigiScan(™) (p = 1.0). Additionally, no statistical differences were seen using the IIEF-EF domain (32.4% of placebo, 29% of treatment; p = 0.79). Multivariable analysis showed no significant differences in erectile function based on treatment intervention. Results did show that African-American men in this cohort were at higher risk for lower RigiScan(™) scores over time (OR: 0.48, p = 0.0399). This study demonstrates that nightly sildenafil citrate does not provide a therapeutic benefit for recovery of erectile function post-prostatectomy when compared to on-demand dosing using both self-reported as well as objective measures. Differences in objective recovery parameters based on patients' race/ethnicity warrant further investigation.
authors.affiliation: Department of Urology, Walter Reed National Military Medical Center, Bethesda, MD, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Kim
authors.affiliation: Department of Urology, Fort Belvoir Community Hospital, Fort Belvoir, VA, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Hawksworth
authors.affiliation: Center for Prostate Cancer Disease Research, Rockville, MD, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Hurwitz
authors.affiliation: Center for Prostate Cancer Disease Research, Rockville, MD, USA.|Department of Surgery, Uniformed Services University, Bethesda, MD, USA.
authors.forename: J
authors.initials: J
authors.lastname: Cullen
authors.affiliation: Department of Urology, Walter Reed National Military Medical Center, Bethesda, MD, USA.|Center for Prostate Cancer Disease Research, Rockville, MD, USA.|Department of Surgery, Uniformed Services University, Bethesda, MD, USA.
authors.forename: I L
authors.initials: IL
authors.lastname: Rosner
authors.affiliation: Department of Urology, UCSF Medical Center, San Francisco, CA, USA.
authors.forename: T F
authors.initials: TF
authors.lastname: Lue
authors.affiliation: Department of Urology, Walter Reed National Military Medical Center, Bethesda, MD, USA.
authors.forename: R C
authors.initials: RC
authors.lastname: Dean
mesh_terms: D004311:Double-Blind Method; D007172:Erectile Dysfunction / Q000188:drug therapy*; D006801:Humans; D008297:Male; D010410:Penile Erection / Q000187:drug effects*; D058986:Phosphodiesterase 5 Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D010919:Placebos; D011446:Prospective Studies; D011467:Prostate / Q000601:surgery; D011468:Prostatectomy / Q000009:adverse effects*; D011471:Prostatic Neoplasms / Q000601:surgery; D020127:Recovery of Function; D000068677:Sildenafil Citrate / Q000008:administration & dosage* / Q000627:therapeutic use*
chemical_list: D058986:Phosphodiesterase 5 Inhibitors; D010919:Placebos; D000068677:Sildenafil Citrate
keywords: erectile dysfunction; nocturnal penile tumescence; prostate cancer; prostatectomy; sildenafil citrate