Ambient air pollution, low-grade inflammation, and lung function: Evidences from the UK Biobank.

The associations of ambient air pollution exposure and low-grade inflammation with lung function remain uncertain. In this study, 276,289 subjects were enrolled in the UK Biobank. Individual exposure to ambient air pollution (including nitrogen dioxide [NO], nitrogen oxides [NO]), and particulate matter [PM, PM PM]) were estimated by using the land-use regression model. Forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV) were tested, and low-grade inflammation score (INFLA score) was calculated for each subject. In this cross-sectional study, the median concentrations of air pollution were 9.89 µg/m for PM, 15.98 µg/m for PM, 6.09 µg/m for PM, 25.60 µg/m for NO, and 41.46 µg/m for NO, respectively. We observed that PM, PM, PM, NO, NO was negatively associated with lung function. Besides, significant positive associations between PM exposure and low-grade inflammation were noted. Per interquartile range (IQR) increase in PM, PM, and PM was related to higher INFLA score, and the β (95 % CI) was 0.06 (0.03, 0.08), 0.03 (0.02, 0.05), and 0.03 (0.01, 0.04), respectively. Additionally, we found significant negative associations between INFLA scores and lung function. One-unit increase in INFLA score was linked with 12.41- and 11.31-ml decreases in FVC and FEV, respectively. Compared with individuals with low air pollution exposure and low INFLA scores, participants with high air pollution and high INFLA scores had the lowest FVC and FEV. Additionally, we observed that INFLA scores could modify the relationships of PM, NO and NO with FVC and FEV (P <0.05). The negative impact of air pollutants on lung function was more pronounced in subjects with high INFLA scores in comparison to those with low INFLA scores. In conclusion, we demonstrated negative associations between ambient air pollution and lung function, and the observed associations were strengthened and modified by low-grade inflammation.