Prolonged Life Expectancy for Those Dying of Stroke by Achieving the Daily PM_2.5 Targets

This time-series study collects data on stroke-related mortality, years of life lost (YLL), air pollution, and meteorological conditions in 96 Chinese cities from 2013 to 2016 and proposes a three-stage strategy to generate the national and regional estimations of avoidable YLL, gains in life expectancy and stroke-related population attributable fraction by postulating that the daily fine particulate matter (PM_2.5) has been kept under certain standards. A total of 1 318 911 stroke deaths are analyzed. Each 10 µg m^-3 increment in PM_2.5 at lag₀₃ is associated with a city-mean increase of 0.31 (95% CI: 0.19, 0.44) years of life lost from stroke. A number of 914.11 (95% CI: 538.28, 1288.94) years of city-mean life lost from stoke could be avoided by attaining the WHO's Air Quality Guidelines (AQG) (25 µg m^-3). Moreover, by applying the AQG standard, 0.11 (0.08, 0.15) years of life lost might be prevented for each death, and about 0.91% (95% CI: 0.62%, 1.19%) of the total years of life lost from stroke might be explained by the daily excess PM_2.5 exposure. This study indicates that stroke patients can have a longer life expectancy if stricter PM_2.5 standards are put in place, especially ischemic stroke patients.