Health care utilization differences between First Nations people and the general population with inflammatory bowel disease: a retrospective cohort study from Saskatchewan, Canada

BACKGROUND: Indigenous people in Canada often face barriers to access specialized care, with limited data in evaluating health care utilization among Indigenous people with inflammatory bowel disease (IBD). We aimed to compare health care utilization between First Nations patients and those in the general population diagnosed with IBD in Saskatchewan. METHODS: We conducted a patient-oriented, population-based, retrospective cohort study by linking administrative health databases of Saskatchewan between fiscal years 1998/99 and 2017/18. We designed and completed this study in partnership with Indigenous patients and family advocates. We applied a validated algorithm to identify IBD incident cases and then used the self-declared First Nations status variable to divide those cases. We applied a 1:5 ratio for age and sex matching and used Cox proportional models to assess associations. Hazard ratios (HRs) and 95% confidence intervals (CIs) were reported. RESULTS: We created a matched cohort with 696 IBD incident cases: 116 First Nations patients and 580 patients in the general population. We observed differences between the groups for IBD-specific hospital admissions (HR 1.33, 95% CI 1.01–1.75), IBD-related hospital admissions (HR 1.55, 95% CI 1.20–2.01), medication claims for IBD (HR 0.52, 95% CI 0.41–0.65) and 5-aminosalicylic acid claims (HR 0.56, 95% CI 0.45–0.71) adjusting by rural or urban residence and diagnosis type. There were no significant differences in the hazard rate of outpatient gastroenterology visits (HR 1.13, 95% CI 0.90–1.41), colonoscopies (HR 1.14, 95% CI 0.92–1.41) and surgeries for IBD (HR 1.14, 95% CI 0.80–1.64). INTERPRETATION: We identified that First Nations patients diagnosed with IBD had a higher rate of hospital admissions owing to IBD than patients in the general population diagnosed with IBD. We also found an inverse association between First Nations status and having prescription medication claims for IBD.