Effect of high-level fine particulate matter and its interaction with meteorological factors on AECOPD in Shijiazhuang, China

Epidemiological evidence of the effect of high-level air pollution and its interaction with meteorological factors on the risk of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is limited. Daily data on AECOPD cases, air pollutants and meteorological factors were collected from 2015 to 2018 in Shijiazhuang. A distributed lag non-linear model (DLNM) was used to explore the lag and cumulative effect of PM 2.5 on the risk of AECOPD. The effect of the interaction between PM 2.5 and meteorological factors on AECOPD was estimated by a generalized additive model (GAM) and a stratification model. A total of 4766 patients with AECOPD were enrolled. After controlling for confounders, each 10 μg/m 3 increase in PM 2.5 led to a 5.8% increase in the risk of AECOPD on day lag 0. The cumulative effect of PM 2.5 on AECOPD risk showed an increasing trend after 3 days. Similar results were observed in both smoking and non-smoking patients. There was an interaction between PM 2.5 and meteorological factors, and the risk of AECOPD was higher in cold and lower humidity conditions than in other conditions. High-level PM 2.5 exposure is positively associated with the risk of AECOPD onset, and the effect of PM 2.5 can be modified by the temperature and relative humidity. Public health guidelines should pay close attention to AECOPD risk under the condition of high-level PM 2.5 with low temperature or low humidity.