Source: J Indian Med Assoc  |  Posted 7 years ago

By Ed Susman

SAN FRANCISCO, CA -- May 12, 2004 -- Men who take nightly doses of sildenafil citrate starting 4 weeks after undergoing bilateral nerve-sparing retropubic radical prostatectomy are more likely to have an early return of spontaneous nocturnal erections, a sign of normalized erectile function, according to a 48-week study.

"These finding may signify a new era in enhancing the recovery of erectile function in this patient population," said Laurence Levine, MD, Professor of Urology and Director, Male Sexual Function and Fertility Program, Rush University Medical Center, Chicago, Illinois.

In his poster presentation here May 10th at the 2004 American Urological Association Annual Meeting, Dr. Levine reported on a trial that assigned 54 men to receive 50 mg or 100 mg of sildenafil or placebo once daily at bedtime for 9 months, starting 4 weeks after prostatectomy.

The men underwent nocturnal penile tumescence and rigidity (NPTR) testing on 2 consecutive nights at weeks 4, 12, 24, 36, and 48 postsurgery. Their erectile function was assessed 8 weeks after discontinuation of drug treatment (week 48) using the International Index of Erectile Function (IIEF) and with the question, "Over the past 4 weeks, have your erections been good enough for satisfactory sexual activity?"

A positive response to treatment was defined as spontaneous erectile function without the use of medication.

Dr. Levine said that 28.6% of the 35 men of sildenafil and 5.3% of 19 men on placebo had a positive response on NPTR testing.

"Our study suggests that sustained, long-term rehabilitation of erectile function is possible," Dr. Levine said. "Following radical retropubic prostatectomy, sexual function is compromised in more than 90% of previously potent patients." He said that the consequences of surgery can reduce the ability to re-establish sexual potency in the majority of cases, but the recurrence of nocturnal erections is seen as a sign that normal functioning can return.

"These results support the consideration of nightly prophylactic sildenafil following prostatectomy to enhance recovery of postoperative erections," Dr. Levine said. "Although optimal time and dosage of sildenafil for sexual rehabilitation has yet to be defined, response was seen as early as 16 weeks after surgery, suggesting that the early initiation of treatment is appropriate."

Lead investigator Harin Padma-Nathan, Clinical Professor of Urology, University of Southern California Keck School of Medicine, Los Angeles, California, said, "The implications of this study are that physicians may have a dramatic, one-shot chance to prevent erectile dysfunction following a radical prostatectomy. We don't know the exact mechanism that is involved in this erectile dysfunction prevention but it may be neuronal regeneration, improvement in endothelial function or another mechanism other than phosphodiesterase-5 inhibition."

The study received funding from Pfizer Inc., New York.

[Presentation title: "Longitudinal Randomized Placebo-Controlled Study of the Return of Nocturnal Erections After Nerve-Sparing Radical Prostatectomy in Men Treated With Nightly Sildenafil Citrate." Abstract #875]