Does Bariatric Surgery Improve Faecal Incontinence? A Systematic Review and Meta-analysis.

INTRODUCTION

Obesity increases the risk of pelvic floor disorders in individuals with obesity, including faecal incontinence. Faecal incontinence (FI) is a condition with important clinical and psychosocial consequences. Though it is associated with obesity, the effect of bariatric surgery on the prevalence and severity of FI is not well reported.

OBJECTIVE

To assess the effect of bariatric surgery on the prevalence and severity of FI in adult patients with obesity.

METHODS

This systematic review was conducted in accordance with the PRISMA statement. Two independent reviewers performed a literature search in MEDLINE, PubMed, Cochrane and Embase from 1 January 1980 to 12 January 2019. We included published English-language randomized control trials and observational studies assessing pre- and post-bariatric surgery prevalence or severity of FI. Random-effects models with DerSimonian and Laird's variance estimator were used for meta-analysis.

RESULTS

Thirteen studies were included, eight assessing prevalence (678 patients) and 11 assessing severity of FI (992 patients). There was no significant difference in prevalence post-operatively overall, though it trended towards a reduction [pooled OR=0.55; =0.075]. There was a significant reduction of FI prevalence in women post-bariatric surgery [95% CI 0.22 to 0.94, p=0.034]. There was a statistically significant reduction in FI prevalence following Roux-en-Y gastric bypass and one anastomosis gastric bypass [0.46, 95% CI 0.26 to 0.81; p=0.007]. There was no significant reduction of incontinence episodes post-operatively [pooled mean difference =-0.17, 95% CI -0.90 to 0.56; p=0.65]. Quality of life (QOL) was not significantly improved post-bariatric surgery [mean differences for the following facets of QOL: behaviour -0.35, 95% CI -0.94 to 0.24; depression 0.04, 95% CI -0.12 to 0.2; lifestyle -0.33, 95% CI -0.98 to 0.33; p values of 0.25, 0.61 and 0.33, respectively].

DISCUSSION

There was a significant reduction in FI prevalence in women and those who underwent Roux-en-Y or one anastomosis gastric bypass. Our results for FI prevalence overall, FI severity and impact on quality of life were not statistically significant. Larger studies are needed in this under-researched area to determine the true effect of bariatric surgery on FI.