Central obesity has been linked to the risk of incontinence

American scientists conducted a population-based study and found that central obesity is associated with an increased risk of fecal incontinence and is a more reliable predictor of this condition than body mass index (BMI). The paper is reported in the journal Clinical Gastroenterology and Hepatology. Walter Chan from Brigham and Women's Hospital and colleagues from various research centers in the United States analyzed data from the NHANES national survey from 2005-2010. The researchers were interested in participants who answered questions related to bowel health. Fecal incontinence (encopresis) was defined as involuntary expulsion of dense or liquid feces and mucus at least once during the previous month. A marker of central (abdominal) obesity was the ratio of waist circumference to height (waist/height index, ITR).

Of the 7,606 participants included, fecal incontinence was noted by 9.2 percent. Its prevalence was found to increase with each quartile increase in both ITR (by 5.3-12.5 percent) and BMI (by 7.1-10.5 percent), with a stronger association with ITR than with BMI in each quartile. In stepwise multivariable logistic regression analysis, only ITR, but not BMI, remained a significant predictor of encopresis when comparing the fourth and first quartiles of body parameters - the odds ratio (OR) was 1.77 (95 percent confidence interval 1.11-2.80; p = 0.017).