Sexual dysfunction is common in the morbidly obese male and improves after gastric bypass surgery.

Background: There has been limited research examining the mechanisms and epidemiology of sexual dysfunction in the morbidly obese. Our objectives were to measure sexual function in the morbidly obese man before and after substantial weight loss induced by gastric bypass surgery.

Study Design: All male patients in undergoing gastric bypass completed the Brief Male Sexual Function Inventory (BSFI) before and after operation. BSFI scores were also compared with published normative controls and analyzed for predictors of change. Mixed models were created to control for age, diabetes, and hypertension.

Results: Ninety-seven men with a mean age of 48 years (range 19 to 75 years) and mean body mass index of 51 kg/m(2) (range 36 to 89 kg/m(2)) underwent gastric bypass surgery. On average, preoperative morbidly obese patients reported a substantially greater degree of sexual dysfunction than did published reference controls in all domains, p < 0.001. Increasing weight independently predicted lower domain scores. Mean postoperative followup length was 19 months (range 6 to 45 months). On average, BSFI scores improved from preoperative levels by bivariate analysis in all categories (means+/-SE): sexual drive (range 0 to 8), 3.9+/-0.3 to 5.3+/-0.3; erectile function (range 0 to 12), 6.4+/-0.5 to 8.9+/-0.5; ejaculatory function (range 0 to 8), 4.9+/-0.4 to 6.3+/-0.4; problem assessment (range 0 to 12), 7.4+/-0.5 to 9.6+/-0.5; and sexual satisfaction (range 0 to 4), 1.6+/-0.2 to 2.3+/-0.2; all p < 0.01. On multivariable analysis, the amount of weight loss independently predicted the degree of improvement in all BSFI domains, p < 0.05. After an average 67% excess weight loss, BSFI scores in postoperative gastric bypass patients approached those of the reference controls.

Conclusions: Men with morbid obesity commonly suffer from profound, but reversible sexual dysfunction.