Introduction and hypothesis: This study aimed to determine whether incontinence to flatus is associated with women's bother in a symptomatic population and with sonographically diagnosed external anal sphincter (EAS) trauma.
Methods: This is a retrospective study of women attending a tertiary urogynecological unit between May 2013 and November 2015. Baseline evaluation included a standardized interview with St. Mark's Incontinence Score (SMIS) and visual analog scale (VAS) assessment for bother, as well as a physical examination and translabial pelvic floor ultrasound. At least one volume obtained covered the entire length of the EAS. These volumes were analyzed with the reviewer blinded to all clinical data.
Results: During the inclusion period, 1104 patients visited the unit. Fifty-three patients were excluded from the study for missing data, leaving 1051 for final analysis. Mean age was 57 years (56-58) and mean body mass index (BMI) 29.1 kg/m2 (28.8-29.6). The prevalence of any anal incontinence (AI) and flatus incontinence were 16.4% (172/1051) and 13.9% (146/1051), respectively. In the group of patients with AI, mean SMIS was 11.8 (11.0-12.6), and mean VAS for AI bother was 5.4 (5.0-5.9). Significant EAS trauma was detected in 9.8% (103/1051) of patients and was associated with flatus incontinence (p = 0.002). Including a flatus incontinence question in the SMIS questionnaire improved the prediction of patient bother from AI (R2 87.8% versus R2 86.3%, p = 0.04).
Conclusions: Flatus incontinence is associated with ultrasound findings of EAS trauma and with higher patient bother from AI.
Keywords: Bother; Exoanal ultrasound; Flatus incontinence; Obstetric anal sphincter trauma; St. Mark’s incontinence score; Visual analogue scale.