Asthma and Chronic Obstructive Pulmonary Disease (COPD) Prevalence and Health Services Use in Ontario Me ´ tis: A Population-Based Cohort Study Andrea S. Gershon 1,2,3,4 *, Saba Khan 2 , Julie Klein-Geltink 2 , Drew Wilton 2 , Teresa To 2,3,4 , Eric J. Crighton 2,5 , Lisa Pigeau 6 , Jo MacQuarrie 6 , Yvon Allard 6 , Storm J. Russell 6 , David A. Henry 2,4 1 Department of Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada, 2 Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada, 3 Child Health Evaluative Sciences, The Hospital for Sick Children, Toronto, Ontario, Canada, 4 University of Toronto, Toronto, Ontario, Canada, 5 Department of Geography, University of Ottawa, Ottawa, Ontario, Canada, 6 Me ´tis Nation of Ontario, Ontario, Canada Abstract Introduction: Chronic respiratory diseases cause a significant health and economic burden around the world. In Canada, Aboriginal populations are at increased risk of asthma and chronic obstructive pulmonary disease (COPD). There is little known, however, about these diseases in the Canadian Me ´tis population, who have mixed Aboriginal and European ancestry. A population-based study was conducted to quantify asthma and COPD prevalence and health services use in the Me ´ tis population of Ontario, Canada’s largest province. Methods: The Me ´tis Nation of Ontario Citizenship Registry was linked to provincial health administrative databases to measure and compare burden of asthma and COPD between the Me ´ tis and non-Me ´ tis populations of Ontario between 2009 and 2012. Asthma and COPD prevalence, health services use (general physician and specialist visits, emergency department visits, hospitalizations), and mortality were measured. Results: Prevalences of asthma and COPD were 30% and 70% higher, respectively, in the Me ´tis compared to the general Ontario population (p,0.001). General physician and specialist visits were significantly lower in Me ´tis with asthma, while general physician visits for COPD were significantly higher. Emergency department visits and hospitalizations were generally higher for Me ´tis compared to non-Me ´tis with either disease. All-cause mortality in Me ´tis with COPD was 1.3 times higher compared to non-Me ´tis with COPD (p = 0.01). Conclusion: There is a high burden of asthma and COPD in Ontario Me ´ tis, with significant prevalence and acute health services use related to these diseases. Lower rates of physician visits suggest barriers in access to primary care services. Citation: Gershon AS, Khan S, Klein-Geltink J, Wilton D, To T, et al. (2014) Asthma and Chronic Obstructive Pulmonary Disease (COPD) Prevalence and Health Services Use in Ontario Me ´tis: A Population-Based Cohort Study. PLoS ONE 9(4): e95899. doi:10.1371/journal.pone.0095899 Editor: Anna Nolan, New York University School of Medicine, United States of America Received November 18, 2013; Accepted April 1, 2014; Published April 23, 2014 Copyright: ß 2014 Gershon et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This study was 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 (MOHLTC). 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 MOHLTC is intended or should be inferred. Funding for this study was provided by the Public Health Agency of Canada. The opinions expressed in this publication are those of the authors/researchers and do not necessarily reflect the official views of the Public Health Agency of Canada. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: andrea.gershon@ices.on.ca Introduction Chronic respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD), are a leading cause of morbidity and mortality worldwide [1]. Globally, 235 million people are believed to suffer from asthma, while COPD is the 4 th leading cause of death [2], [3]. In Canada, asthma affects about 13% of the population and is the most common chronic disease of childhood [4]. COPD (also known as emphysema or chronic bronchitis) affects about 10% of the Canadian adult population and is a leading cause of chronic disease hospitalization [5], [6]. Altogether, chronic respiratory diseases are estimated to cost $154 billion per year in direct and indirect costs nationally [7]. Aboriginal peoples have been found to be at increased risk of chronic respiratory diseases in many countries, including Canada [8]. In a recent Canadian survey study, self-reported prevalence of respiratory disease was significantly higher in Aboriginal peoples aged 15 and older compared to non-Aboriginals (15% vs. 10%) [9]. Aboriginal peoples in Canada also appear to have higher rates of respiratory disease-related emergency department visits and mortality [10], [11]. However, most respiratory disease studies in the Canadian Aboriginal population have focused on First Nations and Inuit peoples; relatively little is known about these diseases in the Me ´tis population. The Me ´tis are one of the founding Aboriginal Peoples of Canada, descended from unions between First Nations women and European men. In the 2011 Canadian National Household PLOS ONE | www.plosone.org 1 April 2014 | Volume 9 | Issue 4 | e95899