The relation between past exposure to fine particulate air pollution and prevalent anxiety: observational cohort study

Objective: To determine whether higher past exposure to particulate air pollution is associated with prevalent high symptoms of anxiety. Design: Observational cohort study. Setting: Nurses’ Health Study. Participants: 71 271 women enrolled in the Nurses’ Health Study residing throughout the contiguous United States who had valid estimates on exposure to particulate matter for at least one exposure period of interest and data on anxiety symptoms. Main outcome measures Meaningfully high symptoms of anxiety, defined as a score of 6 points or greater on the phobic anxiety subscale of the Crown-Crisp index, administered in 2004. Results: The 71 271 eligible women were aged between 57 and 85 years (mean 70 years) at the time of assessment of anxiety symptoms, with a prevalence of high anxiety symptoms of 15%. Exposure to particulate matter was characterized using estimated average exposure to particulate matter