Background Chronic Obstructive Pulmonary Disease (COPD) imposes a significant burden on individuals and communities. While differences in such burden are often studied across countries and healthcare systems, differences within jurisdictions have not been well evaluated. The aim of this study was to assess the trends of, and factors explaining, regional variability in the burden of COPD within a well-defined population with publicly funded healthcare system.

Methodology We used population-based health records of people aged 35 years or older diagnosed with COPD across the 16 health regions of British Columbia, Canada (2010–2020). The primary outcomes were prevalence, incidence, all-cause hospital admissions, and all-cause mortality, while secondary outcomes were COPD- and cardiovascular disease (CVD)-specific hospitalization and mortality. We used generalized linear models to examine how outcomes varied by regions and changed over time, controlling for sex, age, socioeconomic status, and rural/urban residence.

Results Over the 11-year study period, there were 312,014 individuals diagnosed with COPD (48.1% female, mean baseline age: 68.2 years). Across the province, standardized prevalence and all-cause mortality remained relatively stable during the study period, whereas incidence and all-cause hospitalization declined. There were up to a three-fold difference in standardized incidence and prevalence, and up to a two-fold difference in standardized all-cause hospitalization and mortality across regions (all p<0.05). These differences remained significant after controlling for case mix. Among COPD patients, both CVD-specific hospitalization and mortality were higher compared to COPD-specific hospitalization and mortality.

Conclusion Despite being governed by the same universal healthcare system, difference in burden of COPD across geographic regions in this Canadian province was significant. Heterogeneity was more prominent in incidence and prevalence, compared with hospitalization and mortality, suggesting that the variation in the process of care leading to diagnosis is more substantial than variation in COPD outcomes.

MS has received speaker fees and honoraria from AstraZeneca Global, AstraZeneca Canada, and GlaxoSmithKline for independent activities.

This study was funded by AstraZeneca Canada Inc. (F22-03733)

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Human Ethics Board of University of British Columbia (H23-00607) gave ethical approval for this work.

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