Pathophysiology of fecal incontinence in obese patients: A prospective case‐matched study of 201 patients

Abstract

Abstract Background Obesity is an emerging risk factor for fecal incontinence ( FI ). The aim of this study was to characterize pathophysiologic mechanisms of FI in obese patients compared with non‐obese patients in a prospective case‐matched study. Methods The general characteristics and data of the anorectal manometry and endosonography of patients who were evaluated for FI at a single institution from 2005 to 2015 were prospectively assessed. Fecal incontinence was defined by a Cleveland Clinic Incontinence Score ( CCIS ) >4. Obesity was defined by a body mass index ≥30 kg/m 2 . Obese patients were case‐matched with two age‐ and sex‐matched non‐obese patients. Key Results A total of 201 patients were included (67 obese matched with 134 non‐obese). The CCIS , Knowles‐Eccersley‐Scott Symptom Constipation Score and quality of life score were comparable between obese and non‐obese patients with FI . Factors significantly associated with obesity in FI patients were cholecystectomy (odds ratio [ OR ]=3.45 [1.19‐10.32], P =.0230), irritable bowel syndrome ‐ diarrhea ( OR =2.94 [1.22‐7.19], P =.0158), upper part of the anal canal resting pressure ≥22 mm Hg ( OR =3.45 [1.45‐8.76], P =.0045), maximum rectal tolerable volume ≥240 mL ( OR =3.14 [1.34‐7.54], P =.0082), and abdominal pressure ≥28 mm Hg ( OR =2.75 [1.13‐7.33], P =.0248) by multivariate analysis. Conclusions & Inferences Obese patients with FI had a comparable severity of FI to that of non‐obese patients with FI . Regarding obesity in patients with FI , physicians should focus on stool consistency.