Abstract:
Objective To analyze the relationship between daily atmospheric exposure to fine particulate matter (PM2.5) and the number of hospital admissions for chronic obstructive pulmonary disease (COPD) in Lanzhou, China, from 2016 to 2019, and to assess the impact of environmental PM2.5 exposure on hospital admissions of COPD.
Methods Data on atmospheric pollutants, meteorological factors, and hospital admissions of COPD in Lanzhou from 2016 to 2019 were collected. A seasonal trend decomposition model was used to analyze the temporal trends of each factor. A principal component analysis was employed to reduce the dimensionality of meteorological and pollutant data and incorporate them into the model. The risk of hospital admissions for COPD due to PM2.5 exposure was assessed using a generalized additive model and a distributed lag non-linear model.
Results The overall atmospheric PM2.5 concentration in Lanzhou showed a declining trend from 2016 to 2019. Atmospheric PM2.5 exposure increased the risk of hospital admissions for COPD and exhibited a lag effect. For every 10 μg/m3 increase in PM2.5 concentration, the relative risk (RR) of cumulative hospital admissions for COPD over 14 days was 1.071 (95% confidence interval: 1.045-1.097). The peak single-day lag risk from PM2.5 exposure was higher in the cold season than in the warm season, while the 14-day cumulative lag risk was higher in the warm season than in the cold season. Patients aged ≥ 65 years and female patients were more affected by PM2.5 exposure. The impact of environmental PM2.5 exposure on COPD increased with the concentration and was not statistically significant when the PM2.5 concentration was < 27 μg/m3.
Conclusion The impact of atmospheric PM2.5 on COPD is related to age, sex, season (cold or warm), and PM2.5 concentration. Therefore, prevention and control strategies and measures should be formulated according to the characteristics of PM2.5 pollution in different seasons to minimize the harm of PM2.5 exposure.