Long-term exposure to ambient air pollution and effects on cardiovascular, respiratory and neurocognitive health

We plan to study the influence of ambient air pollution on cognitive,cardiovascular and pulmonary health in elderly Canadians who are participating in the Canadian Longitudinal Study on Aging (CLSA). To do this we will compare questionnaire-derived CLSA health data of 20,000 subjects between 45 and 85 years old with their neighborhood concentrations of air pollutants estimated using data from a national network of monitors and also from satellite-derived measurements. This study will also lay the groundwork for future longitudinal studies of the same air quality-health issues as the sample size is increased to 50,000, more in-depth individual data are collected, and participants are followed longitudinally on a regular basis for several years.

We obtained estimates of exposure to ambient air pollution (i.e., ozone, sulfur dioxide, nitrogen dioxide, fine particulate matter) for participants that corresponded to their respective residential postal codes at the time of survey. The source/methods used to obtain such data included Environment Canada’s National Air Pollution Surveillance (NAPS) network of ground monitors, and residential proximity to roadways determined by Geographic Information Systems. We tested associations between air pollution exposure and health indicators from the CLSA.
Using a cross-sectional design, we did not find consistent associations between air pollutants and health. Hopefully a longitudinal design in the future will provide consistent results.