Improvement in life expectancy for ischemic heart diseases by achieving daily ambient PM_(2.5) standards in China

摘要

Background: The potential impacts of daily ambient fine particulate pollution (PM_(2.5)) exposure on year of life lost (YLL) due to ischemic heart diseases (IHD) remain uncertain. We aimed to estimate the improvement in IHD-related life expectancy by attaining the daily air quality standards of ambient PM_(2.5) in China. Methods and results: This study was based on daily mortality data covering 96 Chinese cities from 2013 to 2016. Regional- and national-associations between IHD-related YLLs and daily PM_(2.5) were estimated by generalized additive models. We further evaluated the IHD-related avoidable YLLs with an assumption that the daily PM_(2.5) was below the ambient air quality standards of World Health Organization (WHO) and China, and calculated the improvement of life expectancy by dividing the avoidable YLLs by the overall number of IHD mortality. We totally recorded 1,485,140 IHD deaths from 2013 to 2016. At the national level, we found a positive association between IHD-related YLLs and daily PM_(2.5). Per 10 μg/m~3 increment of four-day averaged ambient PM_(2.5) related to an increase of 0.40 IHD-related YLLs (95% CI: 0.28, 0.51). By achieving the WHO'S air quality guideline, we estimated that an averaged number of 1346.94 (95% CI: 932.61, 1761.27) YLLs can be avoided for the IHD deaths in each city. On average, the life expectancy can be improved by 0.15 years (95% CI: 0.11, 0.19) for each death. Conclusions: Our study provides a nationwide picture of the life expectancy improvements by reaching the daily PM_(2.5) standards in China, indicating that people can live longer in an environment with higher air quality.