Severe Obesity Independently Increases Risk of Fecal Incontinence, highlights study
Severe obesity is an independent risk factor for fecal incontinence (FI) and is associated with significant alterations in anorectal physiology, as reported by a recent study published in the American Journal of Gastroenterology. This study aimed to evaluate the relationship between varying degrees of obesity and the prevalence of FI, as well as to explore the impact of obesity on anorectal function using high-resolution anorectal manometry (HRAM). The study was conducted by Nayna A. and colleagues.
This was a retrospective cohort study of 552 adults who were evaluated for anorectal symptoms by HRAM in a tertiary centre. Patients were divided into four BMI groups:
Non-obese (<25 kg/m²)
Overweight (25–29.9 kg/m²)
Class I obesity (30–34.9 kg/m²)
Class II and III obesity (>35 kg/m²)
Data on demographics, clinical history, surgical/obstetric history, medications, and HRAM findings were reviewed. Statistical analyses included Fisher exact tests, Student t-tests, logistic regression, and general linear regression to determine the relationship between BMI, FI, and anorectal function.
Results
Prevalence of FI and Obesity:
Patients with FI had a significantly higher mean BMI compared to those without FI (27.5 vs 25.9 kg/m², p = 0.013).
FI prevalence was significantly higher in class II and III obesity (31.7%) than in non-obese individuals (13.2%, p = 0.0024).
There were no differences in FI prevalence among the overweight or class I obesity groups.
Multivariable Analysis:
Class II and III obesity was an independent risk factor for FI, with an adjusted OR of 2.89 (95% CI: 1.28–6.50, p = 0.02).
Effect on Anorectal Physiology:
Among FI patients, independently higher BMI correlated with increased volume of first rectal sensation (β-coefficient 1.09, p = 0.016).
Class II and III obesity had a significant potential for increasing the rectal sensitivity, with β-coefficient being 18.9 (p = 0.027).
Class II and III obesity increases the risk of fecal incontinence independently and is associated with significant alterations in rectal sensitivity. Anorectal function testing should be considered an essential component of the diagnostic and management strategy for obese patients experiencing FI. These findings underscore the need for multidisciplinary approaches to address this complex condition effectively.
Reference:
Lodhia NA, Hiramoto B, Horton L, Goldin AH, Chan WW. Obesity is Independently Associated with Increased Risk of Fecal Incontinence and Altered Rectal Sensitivity. Am J Gastroenterol. 2025 Jan 8. doi: 10.14309/ajg.0000000000003308. Epub ahead of print. PMID: 39773574.
