Patterns of inflammatory bowel diseases in Northwestern Ontario: a single-centre cohort study

Health impacts of geographic disparity are amplified in chronic conditions such as inflammatory bowel disease (IBD). Northwestern Ontario (NWO)’s low population density may pose challenges to delivering equitable healthcare. To describe clinical characteristics and care outcomes of IBD patients in NWO. This study identified adult IBD patients assessed by gastroenterologists at the Thunder Bay Regional Health Sciences Centre, the only tertiary centre in NWO. Data from January 1, 1999 to October 1, 2024 were collected. Regions outside of a census metropolitan area were considered rural. Primary outcome was proportion of patients with​​ active disease living in rural versus urban areas. Multivariable logistic regression was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs). We identified the frequency of IBD to be 530 per 100,000 people in NWO. Of 1231 included patients, 634 (51.5%) had ulcerative colitis (UC) and 559 (45.4%) had Crohn’s disease (CD). Baseline demographics were similar between urban and rural residents. Among UC patients, there was no region-dependent difference in the rates of active disease (aOR 0.74; 95% CI 0.46–1.2; p = 0.22). Among CD patients, the rate of active disease was significantly higher among rural residents (aOR 1.59; 95% CI 1.03–2.46; p = 0.038). For both UC and CD, rural residents had lower rates of ED presentation compared to urban residents (aOR 0.44; 95% CI 0.30–0.64; p < 0.01 and aOR 0.65; 95% CI 0.43–0.97; p = 0.036, respectively). NWO carries a significant burden of IBD. Urban and rural residents demonstrate homogeneity in patient and disease characteristics. While rural residence does not preclude care by a gastroenterology specialist, it may pose barriers to timely assessment by a specialist in an acute setting. Future studies examining IBD care in remote Canadian regions may inform strategies to provide equitable care to mitigate the challenges of geographic disparity.