The prevalence of extraintestinal diseases in inflammatory bowel disease: A population-based study

OBJECTIVE: The aim of this study was to determine the prevalence of the maj or extraintestinal manifestations of inflammatory bowel disease (IBD) and t heir relation to disease diagnosis and gender. METHODS: We used the population-based University of Manitoba IBD Database, which includes longitudinal files on all subjects of all health system cont acts identified by International Classification of Diseases, 9th Revision, Clinical Modification codes for visit diagnosis. We extracted a cohort from our database, which included subjects with a known diagnosis of IBD for at least 10 yr. We then determined how many contacts each subject had for eac h of the following extraintestinal IBD-associated immune diseases: primary sclerosing cholangitis, ankylosing spondylitis, iritis/uveitis, pyoderma ga ngrenosum, and erythema nodosum. We calculated the prevalence of the extrai ntestinal diseases using an administrative definition of having at least fi ve health system contacts for the diagnosis in question. This administrativ e definition has previously been validated in Crohn's disease and ulcerativ e colitis (UC). RESULTS: A total of 6.2% of patients with IBD had one of six major extraint estinal diseases studied in this report. Only 0.3% of patients had multiple extraintestinal diseases. Iritis/ uveitis was the most common extraintesti nal disease of all assessed (2.2% of women and 1.1% of men). Iritis/uveitis was more common among women, particularly those with UC (3.8%). Primary sc lerosing cholangitis was most common among men with UC (3%). Ankylosing spo ndylitis was more common among men, and the highest rate was seen among men with Crohn's disease (2.7%). Pyoderma gangrenosum was more common in Crohn 's (1.2%) with no gender predilection. Erythema nodosum was similarly prese nt in Crohn's and UC but was more common among women (1.9%). CONCLUSIONS: The associations of immune mediated diseases in extraintestina l sites may help us to further our understanding of IBD pathogenesis, and i t may help us in developing a paradigm of disease subsets. (Am J Gastroente rol 2001;96:1116-1122. (C) 2001 by Am. Coll. of Gastroenterology).