Socioeconomic Status, Sex, Age and Access to Medications for COPD in Ontario, Canada

Abstract

Disparities in COPD health outcomes have been found with older individuals, men and those of lower socioeconomic status doing worse. We sought to determine if this was due to differences in access to COPD medications. We conducted a retrospective cohort study using population health administrative data from Ontario, Canada, a province with universal prescription drug coverage for older adults. All individuals with COPD aged 67 years and older in 2008 who were not taking inhaled long-acting bronchodilators or inhaled corticosteroids were followed for 2 years. Poisson regression was used to determine the effects of age, sex, and socioeconomic status on the likelihood of initiating one of these medications, after adjusting for potential confounders. Over the study period, 54,050 of 185,698 (29.1%) older individuals with COPD not previously taking any inhaled long-acting bronchodilators or corticosteroids were initiated on one or more of these medications. After adjustment, individuals of low socioeconomic status, measured using neighborhood income level quintiles, were slightly more likely to initiate COPD medications than those of high socioeconomic status (relative risk (RR) 1.05; 95% confidence interval (95% CI) 1.02–1.08). While men received COPD medication at a consistent rate across all age groups, the likelihood that a woman received medication decreased with increasing age. With the exception of older women, there was minimal disparity in prescription for COPD medications. Disparity in health outcomes among Ontario COPD patients is not clearly explained by differences in medication access by socioeconomic status, sex or age.

Keywords:

• community health
• drug coverage
• health inequity
• population health

Disclaimer: The opinions, results and conclusions reported in this paper are those of the authors and are independent from the funding sources. No endorsement by ICES or the Ontario Ministry of Health and Long-Term Care is intended or should be inferred. ICES had no role in the study design, collection, analysis, or interpretation of the data, writing of the report, or in the decision to submit the report for publication.

Author contributions: All authors contributed to the study concept and design, the analysis and interpretation of the data, and the critical revision of the manuscript for important intellectual content; they have all given their final approval to submit the manuscript for publication.

Study data: The datasets used in this study were linked using unique encoded identifiers and analyzed at the Institute for Clinical Evaluative Sciences.

Declaration of Interest Statement

All authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Funding

Dr. Gershon is supported by a Fellowship for Translational Health Research from the Physicians’ Services Incorporated Foundation, Toronto, Ontario and was supported by a New Investigator Award funded by team grant OTG-88591 from the Canadian Institutes of Health Research Institute of Nutrition, Metabolism and Diabetes while working on this study. Dr. To is supported by The Dales Award in Medical Research from the University of Toronto, Toronto, Ontario, Canada. Funding for this project was made available through the Government of Ontario. This study was also supported by the Institute for Clinical Evaluative Sciences (ICES), which is funded by an annual grant from the Ontario Ministry of Health and Long-Term Care.