Apparent temperature and air pollution vs. elderly population mortality in Metro Vancouver.

Abstract

BACKGROUND: Meteorological conditions and air pollution in urban environments have been associated with general population and elderly mortality, showing seasonal variation. OBJECTIVES: This study is designed to evaluate the relationship between apparent temperature (AT) and air pollution (PM₂.₅) vs. mortality in elderly population of Metro Vancouver. METHODS: Statistical analyses are performed on moving sum daily mortality rates vs. moving average AT and PM₂.₅ in 1-, 2-, 3-, 5-, and 7-day models for all seasons, warm temperatures above 15°C, and cold temperatures below 10°C. RESULTS: Approximately 37% of the variation in all-season mortality from circulatory and respiratory causes can be explained by the variation in 7-day moving average apparent temperature (r² = 0.37, p<0.001). Although the analytical results from air pollution models show increasingly better prediction ability of longer time-intervals (r² = 0.012, p<0.001 in a 7-day model), a very weak negative association between elderly mortality and air pollution is observed. CONCLUSIONS: Apparent temperature is associated with mortality from respiratory and circulatory causes in elderly population of Metro Vancouver. In a changing climate, one may anticipate to observe potential health impacts from the projected high- and particularly from the low-temperature extremes.