Hysterectomy and risk of stress-urinary-incontinence surgery: nationwide cohort study

Background Hysterectomy for benign indications has been associated with an increased risk for lower-urinary-tract sequela, but results have been inconclusive. We aimed to establish the risk for stress-urinary-incontinence surgery after hysterectomy for benign indications. Methods We did a nationwide, population-based, cohort study from 1973 to 2003 in Sweden. We identified our population from the Swedish Inpatient Registry. We selected 165 260 women who had undergone hysterectomy (exposed cohort) and a control group of 479 506 individuals who had not had this procedure (unexposed cohort), matched by year of birth and county of residence. In both cohorts, occurrence of stress-urinary-incontinence surgery was established from the Swedish Inpatient Registry. Hazard ratios with 95% CIs were calculated by Cox's proportional-hazards regression. Findings During the 30-year observational period, the rate of stress-urinary-incontinence surgery per 100000 person-years was 179 (95% CI 173-186) in the exposed cohort versus 76 (73-79) in the unexposed cohort. Correspondingly, individuals in the exposed cohort were at increased risk for stress-urinary-incontinence surgery compared with those in the unexposed cohort (hazard ratio 2-4; 95% CI 2.3-2.5), irrespective of surgical technique. Risk for stress-urinaryincontinence surgery varied slightly with time of follow-up: the highest overall risk was recorded within 5 years of surgery (2.7; 2.5-2.9) and the lowest risk was seen after an observation period of 10 years or more (2.1, 1.9-2.2). Interpretation Hysterectomy for benign indications, irrespective of surgical technique, increases the risk for subsequent stress-urinary-incontinence surgery. Women should be counselled on associated risks related to hysterectomy, and other treatment options should be considered before surgery.