Stomach bugs may boost bowel disease risk: study

NEW YORK (Reuters Health) - A bout of diarrheal disease caused by the stomach bugs Salmonella or Campylobacter increases the odds that a person will develop inflammatory bowel disease, with the risk persisting 15 years or more after infection.

The risk is particularly high for hospitalized patients, Dr. Henrik Nielsen from Aarhaus University Hospital in Aalborg, Denmark, and colleagues report in the latest issue of the journal Gastroenterology.

Inflammatory bowel disease, or IBD, refers to a group of conditions, including Crohn’s disease and ulcerative colitis, marked by chronic inflammation in the intestines, leading to symptoms like abdominal pain and diarrhea.

Nielsen and colleagues compared the risks of IBD between 13,148 patients with documented gastroenteritis caused by Salmonella or Campylobacter and 26,216 uninfected controls.

Over the course of 7.5 years, IBD was diagnosed for the first time in far more gastroenteritis patients (107 or 1.2%) than healthy control subjects (73 or 0.5%), according to the researchers.

The increased risk of IBD with exposure to these stomach bugs was highest during the first year.

After accounting for a variety of factors that might influence the risk, stomach bug patients had nearly a threefold increased risk of developing IBD over the entire study period, and nearly a twofold increased risk in the first year after infection.

The risk of IBD was more than fivefold higher for patients hospitalized within days before or after the episode of gastroenteritis.

The increased risk of IBD after the gastroenteritis episode persisted throughout the 15-year observation period and was similar for Salmonella and Campylobacter and for a first-time diagnosis of Crohn’s disease and ulcerative colitis, the investigators report.

SOURCE: Gastroenterology, August 2009.