Association of change in air quality with hospital admission for acute exacerbation of chronic obstructive pulmonary disease in Guangdong, China: A province-wide ecological study.

To assess possible effect of air quality improvements, we investigated the temporal change in hospital admissions for acute exacerbations of chronic obstructive pulmonary disease (AECOPD) associated with pollutant concentrations. We collected daily concentrations of particulate matter (i.e., PM 2.5 , PM 10 and PM coarse), sulfur dioxide (SO 2), nitrogen dioxide (NO 2), carbon monoxide (CO), ozone (O 3), and admissions for AECOPD for 21 cities in Guangdong from 2013 to 2017. We examined the association of air pollution with AECOPD admissions using two-stage time-series analysis, and estimated the annual attributable fractions, numbers, and direct hospitalization costs of AECOPD admissions with principal component analysis. From 2013–2017, mean daily concentrations of SO 2 , PM 10 and PM 2.5 declined by nearly 40%, 30%, and 26% respectively. As the average daily 8 h O 3 concentration increased considerably, the number of days exceeding WHO target (i.e.,100 μg/m³) increased from 103 in 2015–152 in 2017. For each interquartile range increase in pollutant concentration, the relative risks of AECOPD admission at lag 0–3 were 1. 093 (95% CI 1. 06–1. 13) for PM 2.5 , 1. 092 (95% CI 1. 08–1. 11) for O 3 , and 1. 092 (95% CI 1. 05–1. 14) for SO 2. Attributable fractions of AECOPD admission advanced by air pollution declined from 9. 5% in 2013 to 4.9% in 2016, then increased to 6. 0% in 2017. A similar declining trend was observed for direct AECOPD hospitalization costs. Declined attributable hospital admissions for AECOPD may be associated with the reduction in concentrations of PM 2.5 , PM 10 and SO 2 in Guangdong, while O 3 has emerged as an important risk factor. Summarizes the main finding of the work： Reduction in PM may result in declined attributable hospitalizations for AECOPD, while O 3 has emerged as an important risk factor following an intervention. ● The Guangdong province-wide interventional regulation on air pollution is effective. ● Association of air quality with hospital admissions for AECOPD is further confirmed. ● Reduction in PM and SO 2 may particularly lead to declined attributable AECOPD admissions. ● O 3 has emerged as an important risk factor for incidence of AECOPD. ● Principal component analysis is useful in determining major air pollutants. [ABSTRACT FROM AUTHOR]