More Inflammatory Foods, More Fecal Incontinence?

Older women who consumed a proinflammatory diet had a greater risk of fecal incontinence, prospective data from the Nurses’ Health Study found.

In analyses that adjusted for dietary fiber and other relevant covariates, those whose proinflammatory diet scores were in the highest quintile had a 17% greater risk of fecal incontinence compared to those with scores in the lowest quintile (HR 1.17, 95% CI 1.08-1.27), reported Kyle Staller, MD, MPH, of the Massachusetts General Hospital in Boston, and colleagues.

This difference was seen for both solid stool (HR 1.26, 95% CI 1.13-1.41) and liquid stool (HR 1.19, 95% CI 1.08-1.31) incontinence, according to the findings in Clinical Gastroenterology and Hepatology.

Secondary analyses, again looking at the highest versus lowest quintile, showed the relationship was even more pronounced in those with severe fecal incontinence, meaning it occurred weekly:

• Overall: HR 1.25 (95% CI 1.14-1.38)
• Solid stool: HR 1.29 (95% CI 1.14-1.45)
• Liquid stool: HR 1.27 (95% CI 1.11-1.45)

“Proinflammatory diet may contribute to liquid stool FI [fecal incontinence] through interactions with gut microbiota and subsequent bowel disturbances,” Staller’s group suggested. “In solid stool FI, proinflammatory diet may have a direct impact on neuromuscular continence mechanisms, as inflammation may diminish the neuromuscular function and integrity of the pelvic floor.”

“The authors do a good job of establishing a plausible explanation for the relationship between a proinflammatory diet and fecal incontinence,” said Lona Sandon, PhD, RDN, of the University of Texas Southwestern Medical Center in Dallas, who was not involved in the study. “However, we cannot establish a cause and effect with this type of study, and we do not know if this same relationship also occurs in men.”

Fecal incontinence can significantly affect quality of life, especially for older postmenopausal women, Staller’s group noted. Modifiable factors such as diet can help in developing prevention strategies. The new findings build on the researchers’ previous work, which showed that greater fiber intake was linked to a reduced risk of liquid but not solid stool incontinence, “perhaps because fiber normalizes stool consistency through water absorption with stool bulking,” they wrote.

In the current study, the researchers found the association between a proinflammatory diet and incontinence to be independent of fiber intake.

“Because of studies [such] as this, we are beginning to appreciate the proinflammatory and anti-inflammatory effects of foods in the body,” said Gail Cresci, PhD, RD, of the Cleveland Clinic in Ohio. “Low-grade inflammation occurs with many chronic diseases such as hypertension, type 2 diabetes, and cardiovascular disease.”

“Interestingly, these conditions occurred at higher rates in subjects with higher fecal incontinence,” said Cresci, who was not involved in this study. “Moreover, these chronic diseases are associated with the consumption of a ‘Western diet,’ one that includes foods such as red and processed meats, refined grains, and simple sugars.”

“Women of any age can benefit from adopting a less inflammatory diet pattern now to promote health and lower risk or manage symptoms of chronic disease,” Sandon told MedPage Today. “A good place to start is making room for more fruits and vegetables at meals or as snacks, and substituting red or processed meats for other choices such as fish, legumes, beans, and nuts.”

For their study, Staller and colleagues examined data on 57,432 women (median age 73) from the Nurses’ Health Study from 2006 to 2012. Participants enrolled in the study ranged from 30 to 55 years at the time the study began in 1976.

The analysis included those who reported no fecal incontinence at the start of the follow-up period (2008-2012), and excluded those with a history of colorectal cancer, inflammatory bowel disease, and/or immobility. Follow-up questionnaires assessed changes in dietary habits and incontinence episodes, of which 6,896 occurred. Women were followed until death, June 2012, or the date of their last returned questionnaire.

Proinflammatory dietary patterns were measured using the validated energy-adjusted empirical dietary inflammatory pattern (EDIP) score — which looks at intake of 18 food groups predictive of three established plasma inflammatory markers. Higher EDIP scores indicate a more proinflammatory diet: baseline scores were a median 0.56 for the highest quintile and -0.12 for the lowest.

Mean daily fiber intake was higher among those with the least proinflammatory diet based on EDIP scores (19.2 vs 18.1 g for lowest vs highest quintile), as was daily alcohol consumption (13.5 vs 3 g). Red meat intake was lower in those with the least proinflammatory diet (1.1 vs 2.5 servings per week), as was intake of processed meat (0.5 vs 1.5 servings per week).

The researchers also found that a long-term proinflammatory diet, using average EDIP scores from 1984-2010 questionnaires, was linked to a greater risk of fecal incontinence.

Limitations, noted Staller and colleagues, included the possibility for residual confounding, despite controlling for several risk factors for incontinence.