Anal incontinence in women with and those without pelvic floor disorders

To compare the prevalence of anal incontinence and anal sphincter injury in women with pelvic floor disorders (cases) with those in a group of normal control subjects and to evaluate the relationship between sphincter injury and anal incontinence in each group.

We previously reported the results of a cross-sectional study of 100 women with pelvic floor disorders (> or = stage II pelvic organ prolapse and/or urinary incontinence). In this study, we compared those cases with 90 controls (stage 0 or I pelvic organ prolapse and no urinary incontinence) who completed the Rockwood-Thompson fecal incontinence severity index, in which scoring (0-61) is based on the frequency and type of anal incontinence. All women underwent endoanal ultrasonography, and the internal and external anal sphincters were reported as intact versus disrupted. Chi-square test, Student t test, and logistic regression were used for statistical analysis.

Women with pelvic floor disorders were significantly more likely to report anal incontinence (54% versus 17.8%, odds ratio [OR] 5.4, 95% confidence interval [CI] 2.8-10.6, P < .001) and had higher mean fecal incontinence severity index scores (22.3 +/- 13 versus 12.7 +/- 6.3, P = .006) than controls. Cases demonstrated higher rates of anal sphincter defects on ultrasound examination than did controls (52% versus 30%, P = .007). Anal incontinence was significantly associated with anal sphincter injury in women with pelvic floor disorders (OR 36.4, 95% CI 12-114, P < .001) and in controls (OR 5.9, 95% CI 3-11, P = .002).

Anal incontinence was more common in women with pelvic floor disorders than normal controls and may be due to higher rates of anatomic anal sphincter disruption in this group.