The purpose of this study was to find out the frequency, incidence, and age at the beginning of rheumatoid arthritis (RA) among First Nations (FN) and non-FN people in Manitoba, Canada. All Manitobans had access to population-based administrative health records from April 1, 1995, to March 31, 2010. The Federal Indian Registry File was used to identify the FN population. Using Poisson regression, the crude and adjusted RA prevalence and incidence rates were compared and presented as relative rates (RRs) with 95 percent confidence intervals (CIs). Student t tests were used to compare mean (CI) diagnostic age and physician visits. Rheumatoid arthritis crude prevalence grew to 0.65 percent between 2000 and 2010; adjusted RA prevalence in females was 1.0 percent and in males was 0.53 percent. The adjusted RA prevalence in 2009/2010 was greater in FN than non-FN, especially among those aged 29 to 48 years. Between 2000 and 2010, the crude RA incidence fell from 46.7/100,000 to 13.4/100,000 people. Adjusted RA incidence remained greater in FN than in non-FN, especially among those aged 29 to 48 years. The FN population was younger than the non-FN population at the time of diagnosis. The FN population saw more doctors but saw fewer rheumatologists than the non-FN population.
In Manitoba, the prevalence of rheumatoid arthritis is growing while the incidence of RA is declining. The FN population has a higher frequency and incidence of RA, and they are diagnosed at a younger age than the non-FN population. This large care gap, when paired with fewer rheumatologist visits, underlines the need to enhance rheumatology care delivery to the FN population.
