Dr. Bombardier holds a Canada Research Chair in Knowledge Transfer for Musculoskeletal Care (2002–2016) and a Pfizer Research Chair in Rheumatology.
The Epidemiology of Rheumatoid Arthritis in Ontario, Canada†
Article first published online: 28 MAR 2014
Copyright © 2014 by the American College of Rheumatology
Arthritis & Rheumatology
Volume 66, Issue 4, pages 786–793, April 2014
How to Cite
Widdifield, J., Paterson, J. M., Bernatsky, S., Tu, K., Tomlinson, G., Kuriya, B., Thorne, J. C. and Bombardier, C. (2014), The Epidemiology of Rheumatoid Arthritis in Ontario, Canada. Arthritis & Rheumatology, 66: 786–793. doi: 10.1002/art.38306
The opinions, results, and conclusions herein are those of the authors and are independent from the funding sources. No endorsement by the Institute for Clinical Evaluative Sciences or the Ontario Ministry of Health and Long-Term Care is intended or should be inferred.
- Issue published online: 28 MAR 2014
- Article first published online: 28 MAR 2014
- Accepted manuscript online: 10 DEC 2013 02:30PM EST
- Manuscript Accepted: 3 DEC 2013
- Manuscript Received: 30 JUL 2013
- Canadian Institutes of Health Research (CIHR). Grant Number: 119348
- Institute for Clinical Evaluative Sciences, a nonprofit research corporation funded by the Ontario Ministry of Health and Long-Term Care
- Career award from the Fonds de la Recherche en Santé du Québec
- CIHR Fellowship Award in Primary Care Research
- CIHR Fellowship Award in Clinical Research
Epidemiologic assessments of sufficiently large populations are required in order to obtain robust estimates of disease prevalence and incidence, particularly when exploring the influence of various factors (age, sex, calendar time). We undertook this study to describe the epidemiology of rheumatoid arthritis (RA) over the past 15 years.
We used the Ontario Rheumatoid Arthritis administrative Database (ORAD), a validated population-based research database of all Ontarians with RA. The ORAD records were linked with census data to calculate crude and age and sex–standardized prevalence and incidence rates from 1996 to 2010. Vital statistics were used to estimate annual all-cause mortality during the study period.
As of 2010, there were 97,499 Ontarians with RA, corresponding to a cumulative prevalence of 0.9%. Age and sex–standardized RA prevalence increased steadily over time from 473 (95% confidence interval [95% CI] 469–478) per 100,000 population (0.49%) in 1996 to 784 (95% CI 779–789) per 100,000 population (0.9%) in 2010. Age and sex–standardized incidence per 100,000 population ranged from 62 (95% CI 60–63) in 1996 to 54 (95% CI 52–55) in 2010. All-cause mortality decreased by a relative 21.4% since 1996.
Over a 15-year period, we observed an increase in RA prevalence over time. This rise may be attributed to the increasing time to ascertain cases (which may have been latent in the population during earlier years of the study), increasing survival, and/or an increase in the aging background population. Incidence appears to be stable.