McNally MA et al. (2008) Biliary events and increased risk of new onset irritable bowel syndrome: a population-based cohort study. Aliment Pharmacol Ther 28: 334–343

IBS and biliary disease might be linked; however, it is not clear if IBS is a risk factor for biliary disease or if biliary disease predisposes individuals to the development of IBS. McNally et al. performed a population-based, prospective, cohort study to investigate this potential association. Their results suggest that the diagnosis of a biliary event is associated with an approximate twofold increase in the risk of developing IBS.

Between 1988 and 2003, McNally et al. sent a validated gastrointestinal symptom survey and subsequent follow-up survey to a random sample of Olmsted County residents, MN, USA. The medical history of participants was reviewed to identify individuals with a diagnosis of a biliary event (gallstones or cholecystectomy). A total of 819 eligible individuals responded to both surveys. This group included 726 individuals without IBS and 93 individuals with IBS at initial survey. A previous biliary event was identified in 59 individuals at initial survey. During the 10-year follow-up, no significant association was found between the presence of IBS at initial survey and the subsequent development of biliary events. However, 16% of individuals with a history of a biliary event at initial survey developed new onset IBS during follow-up compared with 8.5% of individuals without a biliary event at initial survey or during follow-up (odds ratio 2.2; 95% CI 1.1–4.6; P = 0.03).

In light of these findings, McNally et al. suggest that the diagnosis of a biliary event could possibly be used as a disease marker for IBS.