Effects of exposure to fine particulate matter on the decline of lung function in rural areas in northwestern China.

Our aim was to clarify the main factors associated with lung function and to analyze the correlation between fine particulate matter (PM2.5) and lung function in a rural Chinese population. We analyzed data of 5195 participants in the China Northwest Natural Population Cohort: Ningxia Project who were ≥ 30 years old. They were recruited from 2018 to 2019, underwent spirometry during the physical examination, and completed a self-report questionnaire. A satellite-based spatiotemporal model was used to estimate the 2-year average PM2.5 exposure based on participants' home addresses. A generalized linear mixed model was used to test the relationship between PM2.5 concentration and lung function. Sex, age, exposure to cooking oil fumes, and occupational exposure were negatively correlated (P < 0.05) with forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). Educational status, economic level, tea consumption, and alcohol consumption were positively correlated (P < 0.05) with FVC and FEV1. The adjusted results of each model revealed that FVC and FEV1 decreased with increased exposure to PM2.5. There was a strong negative correlation between a PM2.5 concentration of 35.66 μg/m3 and FVC, FEV1, and FEV1/FVC, with unadjusted hazard ratios of - 0.06 (95% confidence interval, - 0.10 to - 0.01), - 0.13 (- 0.17 to - 0.10), and - 22.10 (- 24.62 to - 19.26), respectively. In conclusion, long-term exposure to high concentrations of ambient PM2.5 is related to reduce lung function among people in rural areas in northwestern China.