Prevalence of anal sphincter defects and association with anal incontinence in women scheduled for pelvic organ prolapse surgery

AIMS Some women with pelvic organ prolapse (POP) have concomitant symptoms of anal incontinence. Our aim was to assess the prevalence of anal sphincter defects and the association with incontinence in women undergoing POP surgery. METHODS Cross-sectional study of 200 women scheduled for POP surgery. They answered yes/no and graded any symptoms of fecal and flatal incontinence on a visual analog scale (0-100). 3D/4D transperineal ultrasound was used to assess internal (IAS) and external anal sphincter (EAS) defects. A defect of ≥30° in ≥4 of 6 slices on tomographic imaging was regarded significant. The association between incontinence and sphincter defects was tested with multivariable logistic regression analysis. RESULTS The prevalence of any sphincter defect was 50/200 (25%). Combined IAS/EAS defect was found in 19/200 (9.5%) women, 8/200 (4.0%) had isolated IAS, and 23/200 (11.5%) had isolated EAS defects. In women with defect and intact IAS, 37% and 11% reported fecal incontinence, respectively, adjusted odds ratio (aOR) 2.3 (95% confidence interval [CI], 0.7-7.0), p = .147 and in women with defect versus intact EAS, 36% and 9% had fecal incontinence, aOR 4.0 (95% CI, 1.5-10.8), p = .005. In women with defect and intact IAS, 85% versus 43% reported flatal incontinence, aOR 5.2 (95% CI, 1.6-17.2), p = .007 and in women with defect versus intact EAS, 71% versus 43% had flatal incontinence, aOR 1.9 (95% CI, 0.8-4.5), p = .131. CONCLUSIONS One of four women scheduled for POP surgery had an anal sphincter defect. EAS defects were associated with fecal incontinence and IAS defects were strongly associated with flatal incontinence.