Irritable Bowel Syndrome: a 10-yr Natural History of Symptoms and Factors That Influence Consultation Behavior

Objective: Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder. The natural history of the condition has been studied extensively, but few studies have examined factors that predict its new onset or health care-seeking behavior.

Methods: Individuals, now aged 50-59 yr, originally enrolled in a population-screening program for Helicobacter pylori (H. pylori) were contacted via postal questionnaire, utilizing the Manning criteria for IBS diagnosis. Baseline demographic data, quality of life, and IBS and dyspepsia symptom data were already on file. Consent to examine primary care records was sought, and data regarding IBS- and dyspepsia-related consultations were extracted.

Results: Of 8,407 individuals originally involved, 3,873 (46%) provided symptom data at baseline and 10-yr follow-up. Of 3,659 individuals without IBS at baseline, 542 (15%) developed new-onset IBS at 10-yr follow-up. After multivariate logistic regression, lower quality of life at baseline (odds ratio [OR] 4.41, 99% confidence interval [CI] 2.92-6.65), dyspepsia at baseline (OR 1.77, 99% CI 1.28-2.46), and female gender (OR 2.14, 99% CI 1.56-2.94) were significant risk factors for new-onset IBS. Of 651 individuals with IBS at either baseline or 10-yr follow-up, 113 (17%) consulted a primary care physician with symptoms. H. pylori infection (OR 1.93, 99% CI 1.03-3.62) and any dyspepsia-related consultation (OR 2.14, 99% CI 1.15-4.00) significantly increased the likelihood of consultation.

Conclusions: Poor quality of life at baseline was a strong predictor of new-onset IBS, but not of IBS-related consultation behavior, which was associated with consultation for dyspepsia during the study period.