The relationship between air pollution and depression and anxiety disorders – A systematic evaluation and meta-analysis of a cohort-based study

Objective: To explore the correlation between air pollution and the onset of depression and anxiety disorders, to draw more comprehensive and integrated conclusions, and to provide recommendations for maintaining mental health and developing policies to reduce mental health risks caused by air pollution. Methods: Meta-analysis of cohort study articles exploring the relationship between air pollution and depression or anxiety disorders included in Pubmed, Web Of Science, CNKI, and Wan Fang database before October 31, 2022, and subgroup analysis of the association between air pollution and depression and anxiety disorders regarding the air pollutants studied, the study population, and Publication bias analysis and sensitivity analysis. Results: A total of 25 articles meeting the criteria were included in this study, including 23 articles examining the relationship between air pollution and depression and 5 articles examining the relationship between air pollution and anxiety disorders. The results of the meta-analysis were based on the type of pollutant and showed that there was a high degree of heterogeneity among the studies on the relationship between air pollution and depression and a significant heterogeneity among the studies on PM 2.5 and the risk of anxiety disorders ( I 2 = 71%, p < .01), so a random-effects model was selected for the analysis. CO, O 3 , and SO 2 and depression onset had combined RR values of 1.10 (1.00, 1.20), 1.06 (0.87, 1.29), 1.17 (1.06, 1.31), 1.19 (0.90, 1.58), 1.03 (0.99, 1.07), and 1.09 (0.97, 1.24), respectively, and PM 2.5 and anxiety The combined RR value for morbidity was 1.10 (0.99, 1.22). The results of sensitivity analysis showed that the combined results were stable and reliable. The results of Egger regression method test showed that none of them had significant publication bias ( p > .05). Limitation: Combined exposure to air pollutants on depression and anxiety, further studies by other researchers are needed in the future. Conclusions: PM 2.5 and NO 2 exposure, especially long-term exposure, may be associated with the onset of depression, and no association was found for the time being between PM 10 , CO, O 3 , SO 2 exposure and depression and PM 2.5 exposure and anxiety disorders.