Approach to post-RP PDE-5 inhibitors inconsequential

Paris-When administering phosphodiesterase type-5 inhibitor therapy in men who have undergone radical prostatectomy, on-demand and rehabilitative therapy appear to be equally effective, according to a study by Italian researchers. The prospective study found no significant difference in postoperative erectile function between the two approaches among men who had undergone bilateral nerve-sparing radical retropubic prostatectomy.

Andrea Salonia, MD, staff urologist at the Vita-Salute San Raffaele University in Milan,working with Francesco Montorsi, MD, presented the study results at the EAU annual congress here. Out of the 1,032 patients with prostate cancer who underwent a prostatectomy at the institution from November 2002 to September 2005, 500 underwent a bilateral nerve-sparing operation with two different surgeons. Data on 233 of these patients were analyzed.

In the study, all patients were carefully evaluated with tests of urinary and general subjective symptoms. Also, the investigators analyzed the postoperative psychometric parameters and coupled them with results of the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) to compare on-demand and rehabilitative PDE-5 inhibitor therapy. Upon discharge from the hospital, the patients were divided into four groups. Group A received no treatment for erectile dysfunction; group B received intracavernosal vasoactive agents; group C received PDE-5 inhibitor therapy on demand; and group D received PDE-5 inhibitor therapy according to a rehabilitative protocol (either on a daily basis or 3 times weekly).

When asked by a member of the audience what his department's gold standard is for post-prostatectomy rehabilitation in patients who were not included in the protocol, Dr. Salonia responded that one of two treatment modalities was used.

"In patients older than 65 years of age, we employ intracavernous treatment very soon after the surgery itself in order to promote a faster and earlier recovery of erectile function, also with PDE-5 in-hibitors on demand," he said. "The second kind of rehabilitative treatment we employ is different types of PDE-5 inhibitors, consisting of once-daily or three-times-a-week dosages."

Factors influencing efficacy

In a separate study, the Vita-Salute San Raffaele group set out to identify the predicting factors for the efficacy of on-demand sildenafil citrate (Viagra), 100 mg, in patients who underwent a bilateral nerve-sparing prostatectomy.

In this study, there were two groups of patients:

The first group consisted of 51 patients younger than 65 years old who had no preoperative use of PDE-5 inhibitor therapy, were operated on by the same surgeon, and were offered eight tablets of sildenafil, 100 mg, on demand at the 3-, 6-, and 12-month follow-up dates. Patients in this group also received specific counseling on how to use the drug and how to facilitate postoperative sexual recovery.

The second group consisted of 55 patients who were randomly identified among those receiving the same operation who were offered the same therapy, regardless of age, use of PDE-5 inhibitors, and surgeon.

All patients were required to respond to a Global Assessment Questionnaire as well as fill out sexual/urinary symptom questionnaires prior to surgery and at the various follow-up dates.

Results showed that the number of sexual attempts and IIEF-EF domain scores were significantly higher in the first group than in the second group at all follow-up dates (p<.01). The researchers concluded that several factors influence the efficacy of sildenafil in this patient population.