Measuring the Short-Term Effect of Ambient Air Pollution on Acute Health Service Use in Ontarians Living with Chronic Obstructive Pulmonary Disease

摘要

Short-term air pollution exposure has been associated with increased morbidity, especially amongst vulnerable populations like those with Chronic Obstructive Pulmonary Disease (COPD). The Air Quality Health Index (AQHI) is an aggregate measure of overall ambient air pollution. It was designed to communicate to the public in an understandable way air quality levels, associated health risks, and strategies to reduce exposure. Its formulation was based on relative mortality and little is known about the association between the AQHI and morbidity amongst individuals with COPD. The objective of my dissertation is to determine the association between ambient air pollution and acute health service use (HSU - hospitalization and emergency department [ED] visits) amongst individuals with COPD. My first original research study determined the perception and knowledge of individuals with COPD, regarding air pollution health risks, assessment, and exposure reduction strategies. The second quantified the association between the AQHI and acute HSU, and the final study examined whether temperature modifies this association. While Canadians with COPD believed that air pollution affects health, their level of knowledge regarding air quality assessment, health risks, and strategies to reduce exposure was lacking. The AQHI was associated with increased risk of acute HSU for non-accidental, COPD and cardiovascular (CVD) causes. A statistically significant association between the AQHI and CVD hospitalization was observed at all temperatures, whereas the association with COPD hospitalization was only significant at higher temperatures. Results also suggested individuals with prior history of hospitalization for COPD, lower respiratory tract infection, or acute myocardial infarction may be more vulnerable. These findings provide important insights for policy and public health strategy. Reducing the negative health effects of air pollution amongst individuals with COPD requires patient and health care provider education, real-time dissemination of air quality levels regardless of temperature, and specific recommendations on how to reduce exposure.