Associations between Coarse Particulate Matter Air Pollution and Cause-Specific Mortality: A Nationwide Analysis in 272 Chinese Cities

Abstract

Background:

Coarse particulate matter with aerodynamic diameter between 2.5 and $10\mathrm{\mu }\mathrm{m}$ ( ${\mathrm{PM}}_{2.5–10}$ ) air pollution is a severe environmental problem in developing countries, but its challenges to public health were rarely evaluated.

Objective:

We aimed to investigate the associations between day-to-day changes in ${\mathrm{PM}}_{2.5–10}$ and cause-specific mortality in China.

Methods:

We conducted a nationwide daily time-series analysis in 272 main Chinese cities from 2013 to 2015. The associations between ${\mathrm{PM}}_{2.5–10}$ concentrations and mortality were analyzed in each city using overdispersed generalized additive models. Two-stage Bayesian hierarchical models were used to estimate national and regional average associations, and random-effect models were used to pool city-specific concentration–response curves. Two-pollutant models were adjusted for fine particles with aerodynamic diameter $\le 2.5\mathrm{\mu }\mathrm{m}$ ( ${\mathrm{PM}}_{2.5}$ ) or gaseous pollutants.

Results:

Overall, we observed positive and approximately linear concentration–response associations between ${\mathrm{PM}}_{2.5–10}$ and daily mortality. A $10{\text{-}\mathrm{\mu }\mathrm{g}/\mathrm{m}}^3$ increase in ${\mathrm{PM}}_{2.5–10}$ was associated with higher mortality due to nonaccidental causes [0.23%; 95% posterior interval (PI): 0.13, 0.33], cardiovascular diseases (CVDs; 0.25%; 95% PI: 0.13, 0.37), coronary heart disease (CHD; 0.21%; 95% PI: 0.05, 0.36), stroke (0.21%; 95% PI: 0.08, 0.35), respiratory diseases (0.26%; 95% PI: 0.07, 0.46), and chronic obstructive pulmonary disease (COPD; 0.34%; 95% PI: 0.12, 0.57). Associations were stronger for cities in southern vs. northern China, with significant differences for total and cardiovascular mortality. Associations with ${\mathrm{PM}}_{2.5–10}$ were of similar magnitude to those for ${\mathrm{PM}}_{2.5}$ in both single- and two-pollutant models with mutual adjustment. Associations were robust to adjustment for gaseous pollutants other than nitrogen dioxide and sulfur dioxide. Meta-regression indicated that a larger positive correlation between ${\mathrm{PM}}_{2.5–10}$ and ${\mathrm{PM}}_{2.5}$ predicted stronger city-specific associations between ${\mathrm{PM}}_{2.5–10}$ and total mortality.

Conclusions:

This analysis showed significant associations between short-term ${\mathrm{PM}}_{2.5–10}$ exposure and daily nonaccidental and cardiopulmonary mortality based on data from 272 cities located throughout China. Associations appeared to be independent of exposure to ${\mathrm{PM}}_{2.5}$ , carbon monoxide, and ozone. https://doi.org/10.1289/EHP2711