Effect of Air Pollution on Anxiety and Depression in Adults: A Cross-Sectional Study

Abstract

Background The association between exposure to air pollutants and mental disorders and its symptoms among adults has been suggested, although results are not consistent. The aim of this study was to analyze the association between exposure to air pollution and presence of symptoms of anxiety and depression, history of anxiety and depression disorders, and history of medication use (including benzodiazepines and antidepressants) in adults living in Barcelona. Methods A total of 958 adults (45 to 74 years old) residents in Barcelona, many of them offspring of Alzheimer disease patients from the ALFA (Alzheimer and Families) study, were included. We used Land Use Regression (LUR) models to estimate residential exposure to PM2.5, PM2.5 absorbance (PM2.5 abs), PM10, PM coarse, NO2 and NOx, measured in 2009. Between 2013 and 2014 participants answered the Goldberg Anxiety and Depression Scale (GADS) to evaluate the presence of symptoms of anxiety and depression. Additionally, self-reported history of anxiety and depression disorders and related medication use was recorded. Results In the city of Barcelona we observed an increased risk of psychiatric history of anxiety and depression disorders (occurring between 2009 and 2014) with increasing air pollution [e.g. for each 5 μg/m3 PM2.5 increase, an increased risk of depression of 4.55 (95% CI; 1.74, 11.87) was reported]. The same pattern was observed for the rest of the evaluated pollutants, showing significant associations for depression. Such associations were consistent with an increased risk of taking medication (occurring between 2009 and 2014) in relation to higher concentrations of air pollutants [e.g. for each 20 μg/m3 NOx increase, an increased risk of antidepressants use of 1.22 (1.04, 1.44) was reported]. However, no clear pattern of association was found for anxiety and depression symptoms measured with the GADS. Conclusions Our study shows that increasing exposure to air pollution may increase the risk of anxiety and depression and related medication intake. Further studies are needed to replicate our results and confirm this association.