Post-radical prostatectomy PDE-5 therapy speeds erectile function return

November 1, 2009

Postoperative pharmacologic therapy enhances the chances of erectile function recovery in virtually all categories of men who undergo bilateral nerve-sparing prostatectomy.

Milan, Italy-Urologists at Universit�ita-Salute San Raffaele in Milan used economic factors and cultural attitudes toward sexuality among Italian men to confirm what many urologists have suspected: postoperative pharmacologic therapy enhances the chances of erectile function recovery in virtually all categories of men who undergo bilateral nerve-sparing prostatectomy.

If there is an exception, it might be in younger men with excellent erectile function prior to the operation, but the researchers say they would nevertheless prescribe and encourage use of phosphodiesterase type-5 inhibitors to improve the likelihood of restoring function.

"This therapy is fundamental, in my opinion," first author Andrea Gallina, MD, a urology resident at the university, told Urology Times. "They need it to increase the probability of recovering erectile function after surgery.

Cultural challenge

The study included 293 consecutive patients who had undergone bilateral nerve-sparing prostatectomy between 2004 and 2008. They divided the group into those who took postoperative PDE-5 inhibitors and those who did not and followed those who had not taken medication to treat erectile function.

In the U.S. and a number of other Western countries, it would be impossible to randomize patients into a cohort that would receive pharmacologic therapy and one that would not because the efficacy of the available agents has been well demonstrated. The Italian patients randomized themselves.

"In Italy, patients have to pay for these medications, and some cannot afford the therapy," Dr. Gallina explained. "The other problem is that no small part of the population feels they do not need PDE-5 inhibitors. They have a sort of 'I can make it on my own' attitude toward recovery."

Each cohort was further stratified by age, preoperative IIEF score, body mass index, and number of comorbidites (1 vs. 2+ on the Charlson Comorbidity Index). Patients were assessed every 3 months to a median follow-up of 26.8 months. Erectile function recovery was defined as obtaining an IIEF score of ≥22.

The rate of function recovery in men not taking post-op therapy was a modest 35.8%.

Age, IIEF are key factors

Factors having the greatest influence on recovery appear to have been age and IIEF scores. Seventy-two percent of patients age 55 years or younger recovered sexual function compared to 30% of patients age 70 or older. Well over half (56.6%) of patients with a preoperative IIEF score of ≥26 recovered sexual function compared to 18% patients with IIEF scores of 11 to 17 or lower.

Body mass index also bore an influence. More than 40% of men with a BMI ≤25 kg/m2 evidenced recovery of some function compared to approximately 30% of those with a BMI >30 kg/m2 ; however, this difference did not reach significance in either univariate or multivariate analysis.

Those men with one comorbidity showed a slightly better chance of recovery than those with two or more. In almost all categories of stratification, recovery rates reached a plateau at 24 months.

"We have always thought, and have scientifically known, that a good surgery is mandatory for recovery of erectile function. Now we know for certain that PDE-5 inhibitors improve the chances of recovery and may accelerate those chances," said Dr. Gallina.

"Our rehabilitative therapy usually consists of tadalafil every other day, or either sildenafil or vardenafil on demand."

The mechanisms that allow PDE-5 inhibitors to speed recovery remain unclear in humans, but Dr. Gallina postulates that these drugs reduce or prevent fibrosis and the associated venous leakage following surgical procedures.

Dr. Montorsi is a consultant and adviser for Bayer Healthcare, Eli Lilly, and Pfizer.