Outdoor Air Pollution in Canada: Associations with Major Depressive Episodes and Depressive Symptoms
| dc.contributor.advisor | Patten, Scott | |
| dc.contributor.author | Dores, Ashley Katherine | |
| dc.contributor.committeemember | Fick, Gordon | |
| dc.contributor.committeemember | MacMaster, Frank | |
| dc.date | 2021-11 | |
| dc.date.accessioned | 2021-07-16T16:25:46Z | |
| dc.date.available | 2021-07-16T16:25:46Z | |
| dc.date.issued | 2021-07-08 | |
| dc.description.abstract | Objective: The objective of this thesis was to assess whether exposure to increased levels of outdoor air pollution is associated with an increased prevalence of major depression. Methods: The prevalence of major depressive episode (MDE) from 2011 to 2014 and moderate-severe depressive symptoms of major depression from 2015-2016 were derived from six consecutive survey years of the annual Canadian Community Health Survey (CCHS). The Canadian Urban Environmental Research Consortium provided estimates of the annual average concentration of fine particulate matter ≤2.5 micrometers (µm) in diameter (PM2.5) (2012-2015), ozone (O3) (2013-2015), sulfur dioxide (SO2) (2011-2015), and nitrogen dioxide (NO2) (2012). Outdoor air pollution data was linked with the annual CCHS survey data via 6-digit residential postal codes. Long-term exposure to increased levels of residential outdoor air pollution was defined by the upper quartile of the annual average concentration of PM2.5, O3, SO2, and NO2. Log-binomial models were used to estimate prevalence ratios with corresponding 95% confidence intervals. Single outdoor air pollutant models included adjustment for age, sex, marital status, income, education, employment status, urban versus rural households, cigarette smoking, and chronic illness. Results: Overall, these findings did not suggest that exposure to increased levels of outdoor air pollution is associated with an elevated prevalence of MDE or moderate-severe symptoms of major depression. No evidence of modification or confounding was observed. Conclusions: The analysis did not find evidence that outdoor air pollution is associated with major depression in Canada. Although outdoor air pollution was not identified as a neighbourhood-level determinant of major depression, these results should be generalized to other countries with caution. The null results that we observed may be due to the relatively low levels of outdoor air pollution in Canada. Air pollution at these levels may not be sufficient to activate the relevant mechanisms of major depression (e.g., inflammation, aggravation of chronic conditions, production of depressive symptoms). Future research should examine whether outdoor air pollution is linked to major depression in regions with higher levels of outdoor air pollution or during intervals of elevated exposure such as those that may occur during natural disasters. | en_US |
| dc.identifier.citation | Dores, A. K. (2021). Outdoor Air Pollution in Canada: Associations with Major Depressive Episodes and Depressive Symptoms (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. | en_US |
| dc.identifier.doi | http://dx.doi.org/10.11575/PRISM/39012 | |
| dc.identifier.uri | http://hdl.handle.net/1880/113632 | |
| dc.language.iso | eng | en_US |
| dc.publisher.faculty | Cumming School of Medicine | en_US |
| dc.publisher.institution | University of Calgary | en |
| dc.rights | University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. | en_US |
| dc.subject.classification | Epidemiology | en_US |
| dc.subject.classification | Mental Health | en_US |
| dc.title | Outdoor Air Pollution in Canada: Associations with Major Depressive Episodes and Depressive Symptoms | en_US |
| dc.type | master thesis | en_US |
| thesis.degree.discipline | Medicine – Community Health Sciences | en_US |
| thesis.degree.grantor | University of Calgary | en_US |
| thesis.degree.name | Master of Science (MSc) | en_US |
| ucalgary.item.requestcopy | true | en_US |