Thesis Format
Integrated Article
Degree
Doctor of Philosophy
Program
Epidemiology and Biostatistics
Supervisor
Burneo, Jorge G.
2nd Supervisor
Speechley, Kathy N.
Co-Supervisor
Abstract
Air and noise pollution have been associated with the onset and symptoms of many health conditions, but its association with unprovoked seizures and new-onset epilepsy is unclear. The objectives of this thesis were to: (1) synthesize the literature examining associations between short- and long-term exposure to outdoor air and noise pollution and the risk of unprovoked seizures and new-onset epilepsy; and estimate the risk of new-onset epilepsy associated with long-term outdoor exposure to (2) fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ground-level ozone (O3), and (3) road traffic noise. We addressed Objective 1 using a systematic review and meta-analysis, including observational and ecological studies assessing the associations of air and noise pollution with unprovoked seizures and new-onset epilepsy. We addressed Objectives 2 and 3 using population-based nested case-control studies, including adults residing in Ontario as of January 1, 2010, without a history of epilepsy. Air and noise pollution were measured using three-year averages of the annual average PM2.5, NO2, and O3 concentrations, and the 8-hour nighttime, 16-hour daytime, and 24-hour road traffic noise levels, at the participant’s residence. We included only one study in the systematic review and meta-analysis that estimated the association of air pollution with new-onset epilepsy. No studies estimated the associations of noise pollution with either unprovoked seizures or new-onset epilepsy. We included 16 studies of the association of air pollution with unprovoked seizures, eight of which were synthesized quantitatively. We found that short-term exposure to O3 may reduce the risk of unprovoked seizures, and short-term exposure to NO2 and carbon monoxide may increase this risk. When estimating the association of air pollution with new-onset epilepsy, we found positive associations for O3 and PM2.5, and a negative association for NO2. When estimating the association of road traffic noise with new-onset epilepsy, we found positive but statistically insignificant associations with the 8-hour nighttime and 24-hour daytime estimates. Although additional research is needed, these findings indicate that air and noise pollution may be potential interventional targets to prevent the onset of epilepsy and improve patient quality of life.
Summary for Lay Audience
The association of air and noise pollution with seizures and the development of epilepsy is currently unclear. Therefore, the objectives of this thesis were to: (1) summarize prior research that examined the associations of outdoor air and noise pollution with the risk of seizures and the development of epilepsy; and estimate the risk of developing epilepsy associated with long-term exposure to (2) fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ground-level ozone (O3), and (3) road traffic noise. We addressed Objective 1 by searching for and summarizing prior research that has estimated the associations of air or noise pollution with seizures or the development of epilepsy. We addressed Objectives 2 and 3 using population-based studies, including adults living in Ontario as of January 1, 2010, without a history of epilepsy. Air and noise pollution were measured using three-year averages of the annual average PM2.5, NO2, and O3 concentrations, and the 8-hour nighttime, 16-hour daytime, and 24-hour road traffic noise levels at participants’ postal code. We found only one study that estimated the association of air pollution with new-onset epilepsy. We did not find any studies that estimated the associations of noise pollution with either seizures or the development of epilepsy. We found 16 studies of the association of air pollution with seizures. Of these 16 studies, we could average the effects estimated across eight, finding that higher short-term O3 exposure may reduce the risk of seizures, and higher short-term NO2 and carbon monoxide exposure may increase this risk. In our first study, which assessed the association of air pollution with the development of epilepsy, higher O3 and PM2.5 exposure was associated with an increased risk, and higher NO2 exposure was associated with a lower risk. In our second study, which assessed the association of road traffic noise with the development of epilepsy, we found a potential association between higher road traffic noise levels, especially at night, and an increased risk of developing epilepsy. Although additional research is needed, these findings suggest that reducing air and noise pollution may reduce seizures and prevent the development of epilepsy.
Recommended Citation
Antaya, Tresah C., "Association of Air and Noise Pollution with Unprovoked Seizures and New-Onset Epilepsy" (2024). Electronic Thesis and Dissertation Repository. 10647.
https://ir.lib.uwo.ca/etd/10647
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