Bariatric surgery improves urinary incontinence but not anorectal function in obese women

While the association between obesity and urinary incontinence (UI) in women has been clearly documented, the relationship with anal incontinence (AI) is less well defined; moreover, while bariatric surgery has been shown to improve UI, its effect on AI is still unclear.

A total of 32 obese women were studied by means of PFDI-20 and PFIQ-7 questionnaires and anorectal manometry before and after bariatric surgery and compared with 71 non-obese women.

Obese women showed worse overall questionnaire results (OR 5.18 for PFDI-20 and 2.66 for PFIQ-7). Whereas obese women showed worse results for urinary sub-items and a higher urge UI incidence (43.8 vs 18.3 %, p = 0.013), they did not show worsening in colorecto-anal symptoms. Post-operatively, median PFDI-20 total score did not change (24.2 vs 26.6, p = ns), while there was an improvement in urinary score (14.6 vs 8.3, p < 0.001); median PFIQ-7 improved (4.8 vs 0.0, p = 0.044), but while the urinary score improved (2.4 vs 0.0, p = 0.033), the colorecto-anal score did not change significantly. Although after surgery urge UI decreased from 43.8 to 15.6 % (p = 0.029), the incidence of any AI increased from 28.1 to 40.6 % (p = ns) and flatus incontinence increased from 18.8 to 37.5 % (p = ns). Anorectal manometry did not show significant changes after surgery.

Obese women had worse questionnaire results, but while showing a higher incidence of UI, they did not experience anorectal function worsening. After bariatric surgery, there was a slight improvement in PFD symptoms related to UI, but anorectal function did not change significantly and flatus incontinence increased.