The association between high particulate matter pollution and daily cause-specific hospital admissions: a time-series study in Yichang, China

Particulate matter (PM) air pollution is one of the major causes of morbidity and mortality in China. In this study, we estimated the short-term effects of PM on cause-specific hospitalization in Yichang, China. Daily data for PM level, meteorological factors, and hospital admissions (total hospitalization counts = 391,960) in Yichang between 2015 and 2017 were collected. We conducted a time-series study and applied a generalized additive model to evaluate the association between every 10 μg/m³ increment of PM and percent increase of hospitalization. We found positive and statistically significant associations between PM and hospital admissions for multiple outcomes, including all-cause, total respiratory, total cardiovascular diseases, and disease subcategories (hypertensive disease, coronary heart disease, stroke and the stroke subtype, chronic obstructive pulmonary disease, and lower respiratory infection). Each 10 μg/m³ increase in PM_2.5 at Lag01 (a moving average of Lag0 to Lag1), was significantly associated with an increase of 1.31% (95% CI: 0.79%, 1.83%), 1.12% (95% CI: 0.40%, 1.84%), and 1.14% (95% CI: 0.53%, 1.75%) in hospitalizations for all-cause, CVD, and respiratory, respectively. The association for PM₁₀ with all-cause, CVD, and respiratory admissions was similar but weaker than PM_2.5. The effect on admissions persisted for up to 7 days, and peaked at Lag01. The associations between PM and all-cause hospitalizations were stronger among older individuals and in cold seasons. It is therefore important to continue implementation of emission abatement and other effective measures in Yichang and other cities in China.