LONG-TERM EFFECT OF SILDENAFIL CITRATE ON ERECTILE
DYSFUNCTION AFTER RADICAL PROSTATECTOMY:
3-YEAR FOLLOW-UP
RUPESH RAINA, MILTON M. LAKIN, ASHOK AGARWAL, RAKESH SHARMA, KUSH K. GOYAL,
DROGO K. MONTAGUE, ERIC KLEIN, AND CRAIG D. ZIPPE
ABSTRACT
Objectives. To evaluate the long-term effect and safety of sildenafil citrate for the treatment of erectile
dysfunction after radical prostatectomy (RP).
Methods. The study consisted of 91 patients with erectile dysfunction from our institution who received oral
sildenafil citrate after RP. We surveyed these patients using a self-administered questionnaire during the first
year of sildenafil citrate use to determine treatment satisfaction, patient compliance, and safety. Those who
had responded positively to the drug were surveyed again 3 years later (n = 48). Sildenafil citrate was
prescribed at a dose of 50 mg and increased to 100 mg if needed. Data were collected from a self-
administered questionnaire using the abridged five-item version of the International Index of Erectile
Function questionnaire, referred to as the Sexual Health Inventory of Men, and the Erectile Dysfunction
Inventory of Treatment Satisfaction. The patients were stratified according to the type of nerve-sparing (NS)
RP procedure they underwent: bilateral NS, unilateral NS, and non-NS.
Results. At 3 years, 31 (71%) of the 43 patients who had returned the second surveys were still responding
to sildenafil. Of these 31 respondents, 10 (31%) had augmented their dose from 50 to 100 mg. The dropout
rate was 27%; 6 of 12 had discontinued because of the return of natural erections, 5 because of a loss of
efficacy, and 1 because his spouse had died. No differences were found in the 1-year and 3-year five-item
International Index of Erectile Function (Sexual Health Inventory of Men) and Erectile Dysfunction Inventory
of Treatment Satisfaction scores between the NS groups. The most common side effects at 3 years were
headache (12%), flushing (10%), and blue or blurred vision (2%). No patient discontinued the drug at 3 years
because of side effects.
Conclusions. The results of this study indicate that the vast majority of patients with erectile dysfunction
after RP who initially respond to sildenafil continue to do so at 3 years and are satisfied and compliant with
the treatment regimen. UROLOGY 62: 110–115, 2003. © 2003 Elsevier Inc.
R
adical prostatectomy (RP) has been the refer-
ence standard treatment for organ/specimen-
confined prostate cancer for several decades. Al-
though improved surgical techniques have
decreased the rate of “total” and stress-induced in-
continence to less than 10%, urologists still report
that most patients experience erectile dysfunction
(ED) after RP.
1,2
The treatment algorithm for pa-
tients with ED after RP improved dramatically in
1998 when the first effective oral therapy—silde-
nafil citrate (Viagra, Pfizer Pharmaceutical)— be-
came available. Following the publication by
Moreland et al.,
3
in 1998, sildenafil revolutionized
the evaluation and treatment of ED to the extent
that oral therapy is now the first treatment option
for patients with ED caused by a variety of organic
and psychogenic causes. Data from various clinical
trials have demonstrated improved erectile func-
tion in patients with a cross-section of ED etiolo-
gies.
4
However, early reports did not stratify the
various types of organic etiologies and did not in-
clude pertinent data for the subset of patients who
C. D. Zippe is a member of the speaker’s bureau for Pfizer. M. M.
Lakin is a consultant to, and a member of the speaker’s bureau for,
Pfizer.
From the Glickman Urological Institute and Andrology-Oncol-
ogy Research Laboratory, Cleveland Clinic Foundation, Cleve-
land, Ohio
Reprint requests: Craig D. Zippe, M.D., Glickman Urological
Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue,
Desk A100, Cleveland, OH 44195
Submitted: November 4, 2002, accepted (with revisions):
February 11, 2003
ADULT UROLOGY
© 2003 ELSEVIER INC. 0090-4295/03/$30.00
110 ALL RIGHTS RESERVED doi:10.1016/S0090-4295(03)00157-2