Abstract: PD18-10
Sources of Funding: U.S. Agency for Healthcare Research and Quality (Grants 1R01HS019356 and 1R01HS022640-01); the National Cancer Institute, National Institutes of Health (Grant R01-CA114524), and the following contracts to each of the participating institutions: N01-PC-67007, N01-PC-67009, N01-PC-67010, N01-PC-67006, N01-PC-67005 and N01-PC-67000, and through a contract from the Patient-Centered Outcomes Research Institute

Introduction

Nerve sparing (NS) contributes to recovery of sexual function after prostatectomy, but may not be necessary in men with low baseline function. We evaluated the effect of NS in men with low and high baseline function over 3 years after prostatectomy.

Methods

The Comparative Effectiveness Analysis of Surgery and Radiation (CEASAR) study is a prospective, population-based, observational study of men with localized prostate. Patient-reported sexual function was measured using the 26-item Expanded Prostate Index Composite (EPIC) at baseline, 6, 12, and 36 months after treatment. To identify the effect of NS on post-treatment sexual function for both high and low baseline sexual function, we fit unadjusted and adjusted models with interactions between nerve sparing status, time since treatment and baseline sexual function, controlling for comorbidity, race, use of erectile aids, disease risk, depression, and anxiety scores in the adjusted model. R² plot was used to show the contribution of each factor to sexual function outcome. NS status was defined as none (NNS), unilateral (UNS) or bilateral (BNS), according to the operative report. We grouped NNS with UNS, as there was negligible difference in EPIC domain scores. We dichotomized baseline sexual function into low (EPIC domain score <80) and high (>80).

Results

Among 1373 participants, 415 men with high baseline sexual function underwent BNS and 84 underwent NNS/UNS. In 648 men with low baseline function, 365 men underwent BNS and 86 men underwent NNS/UNS. From the unadjusted model, men with high baseline function had a 7.8 point difference (CI -0.4, 16) in EPIC domain scores between NNS/UNS and BNS at 3 years and in men with low baseline function, there was an 8.9 point difference (CI 2.5, 15.4). In the adjusted model, there was also no statistically significant difference between NNS/UNS and BNS. Baseline sexual function and time since treatment accounted for most of the variation in sexual function scores.

Conclusions

These data suggest that BNS has a small impact on function, the same magnitude of effect regardless of baseline function, raising concern that operative reports inadequately reflect actual degree of NS. We confirm that baseline function is the main driver of post-prostatectomy sexual function.

Funding

U.S. Agency for Healthcare Research and Quality (Grants 1R01HS019356 and 1R01HS022640-01); the National Cancer Institute, National Institutes of Health (Grant R01-CA114524), and the following contracts to each of the participating institutions: N01-PC-67007, N01-PC-67009, N01-PC-67010, N01-PC-67006, N01-PC-67005 and N01-PC-67000, and through a contract from the Patient-Centered Outcomes Research Institute