Irritable bowel syndrome and the incidence of colorectal neoplasia: a prospective cohort study with community-based screened population in Taiwan
Menée à Taïwan auprès de 39 384 participants âgés de plus de 40 ans ayant participé, depuis 1999, à un programme de dépistage de cancer colorectal par test de recherche de sang occulte dans les selles, cette étude de cohorte prospective évalue l'association entre un syndrome de l'intestin irritable et le risque de néoplasie colorectale
Background: We aim to report the prevalence of irritable bowel syndrome (IBS) and elucidate the influence of IBS on the incidence of colorectal neoplasm through a community-screening-based, longitudinal follow-up study. Methods: We enroled 39 384 community residents aged 40 years or older who had participated in a community-based colorectal cancer-screening programme with an immunochemical faecal occult test since 1999. We followed a cohort that was free of colorectal neoplasm (excluding colorectal neoplasm at baseline) to ascertain the incident colorectal neoplasm through each round of screening and used a nationwide cancer registry. Information on IBS was obtained by linking this screened cohort with population-based health insurance claim data. Other confounding factors were also collected via questionnaire or biochemical tests. Results:The overall period prevalence of IBS was 23%, increasing from 14.7% for subjects aged 40–49 years to 43.7% for those aged 70 years and more. After controlling for age, gender and family history of colorectal cancer, screenees who had been diagnosed as having IBS exhibited a significantly elevated level (21%; adjusted hazard ratio (HR)=1.21 (95% CI: 1.02–1.42)) of incident colorectal adenoma compared with those who had not been diagnosed with IBS. A similar finding was noted for invasive carcinoma; however, the size of the effect was of borderline statistical significance (adjusted HR=1.20 (95% CI: 0.94–1.53)). Conclusions: IBS led to an increased risk for incident colorectal neoplasm.