Abstract
Objectives
To estimate provincial all-cause mortality rates of Saskatchewan people with rheumatoid arthritis (RA) for comparison with the general population over time and between different geographic regions.
Methods
Saskatchewan provincial administrative health databases (2001–2019) were utilized as data sources. Two RA case definitions were employed: (1) ≥ 3 physician billing diagnoses, at least 1 from a specialist (rheumatologist, general internist or orthopaedic surgeon) within 2 years; (2) ≥ 1 hospitalization diagnosis (ICD-9 code 714, and ICD-10-CA codes M05, M06). Data from these definitions were combined to create an administrative data RA cohort. All-cause mortality rates across geographic regions, between rural/urban residences and between sexes were examined.
Results
Over an 18-year span, between fiscal-year 2001–2002 and fiscal-year 2018–2019, age- and sex-adjusted mortality rates ranged from 17.10 to 21.04 (95% CI 14.77, 19.44; 18.03, 24.05)/1000 RA person-years, compared with mortality rates for the general Saskatchewan population without RA, which ranged from 9.37 to 10.88 (95% CI 9.23, 9.51; 10.72, 11.05)/1000 person-years. Fiscal-year mortality rate ratios ranged from 1.82 to 2.13 (95% CI 1.56, 2.13; 1.83, 2.46). Provincial mortality rates were higher in men than in women for both general and RA populations. Northern Saskatchewan mortality rates were significantly higher in the general population but did not achieve significance compared with other provincial regions for the RA population. Regression analysis identified age, male sex, RA and geographic region as factors contributing to increased mortality. A trend towards lower mortality rates over time was observed.
Conclusion
Higher mortality rates were observed in the RA population overall. Men had higher mortality rates, as did residents of Northern Saskatchewan compared with residents of other regions for the general population.
Résumé
Objectifs
Estimer les taux de mortalité provinciaux, toutes causes confondues, des habitants de la Saskatchewan atteints de polyarthrite rhumatoïde (PR) pour les comparer aux taux dans la population générale au fil du temps et entre différentes régions géographiques.
Méthode
Nos données sont extraites des bases de données administratives sur la santé de la Saskatchewan (2001–2019). Deux définitions de cas ont été employées pour la PR : 1) ≥ 3 factures de diagnostic médical, dont au moins une d’un(e) spécialiste (rhumatologue, interniste général[e] ou chirurgien[ne] orthopédiste) en l’espace de deux ans; 2) ≥ 1 diagnostic d’hospitalisation (code CIM-9 714 et codes CIM-10-CA M05 et M06). Les données de ces définitions ont été combinées pour créer une cohorte de personnes atteintes de PR dans les données administratives. Les taux de mortalité toutes causes confondues entre les régions géographiques, entre les lieux de résidence urbains et ruraux et entre les sexes ont été examinés.
Résultats
En l’espace de 18 ans, entre les exercices 2001-2002 et 2018-2019, les taux de mortalité rajustés selon l’âge et le sexe ont varié entre 17,10 et 21,04 (IC de 95 % : 14,77-19,44; 18,03-24,05)/1000 personnes-années pour les personnes atteintes de PR, tandis que les taux de mortalité de la population générale de la Saskatchewan non atteinte de PR se sont situés entre 9,37 et 10,88 (IC de 95 % : 9,23-9,51; 10,72-11,05)/1000 personnes-années. Les rapports de taux de mortalité par exercice ont varié entre 1,82 et 2,13 (IC de 95 % : 1,56-2,13; 1,83-2,46). Les taux de mortalité provinciaux des hommes étaient supérieurs à ceux des femmes, tant dans la population générale que chez les personnes atteintes de PR. Les taux de mortalité dans le Nord de la Saskatchewan étaient sensiblement plus élevés que dans les autres régions de la province pour la population générale, mais pas sensiblement plus élevés pour la population atteinte de PR. Selon les analyses de régression, l’âge, le sexe masculin, la PR et la région géographique étaient des facteurs contribuant à une mortalité accrue. Une tendance à la baisse des taux de mortalité au fil du temps a été observée.
Conclusion
Dans la population atteinte de PR, des taux de mortalité plus élevés ont été observés globalement. Dans la population générale, les taux de mortalité des hommes et ceux des résidents du Nord de la Saskatchewan étaient plus élevés que ceux des résidents des autres régions.
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Data availability
Data for this study were derived from Saskatchewan health administration databases.
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Funding
This work was supported by the Noreen Sutherland— Rheumatoid Arthritis—Royal University Hospital Foundation Endowment Fund.
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This study complies with the Declaration of Helsinki and was approved by the University of Saskatchewan Biomedical Research Ethics Board (BIO-REB 13-336).
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Taylor-Gjevre, R.M., Nair, B.V., Jin, S. et al. Higher mortality rates associated with rheumatoid arthritis in Saskatchewan, Canada, 2001–2019. Can J Public Health 112, 722–732 (2021). https://doi.org/10.17269/s41997-021-00476-w
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DOI: https://doi.org/10.17269/s41997-021-00476-w