Air pollution associates with poor mental health and amplifies the premature cardiovascular death in the United States: longitudinal nationwideanalysis

Abstract Background While air pollution (i.e., particulate matter with aerodynamic diameter ≤2.5mm-PM2.5) and poor mental health (PMH) are linked to premature all-cause mortality, their interrelationship and joint impact on premature cardiovascular mortality (PCVM) in the United States, is unknown. Purpose Herein we sought to test the hypothesis that high exposure to PM2.5 associates with heightened PMH and an amplified PCVM risk related to PMH. Methods We analyzed annual PM2.5 levels and average PMH (days) data from the Center for Disease Control and Prevention (CDC) PLACES databases across 3047 U.S. counties. PM2.5 exposure was dichotomized (high/low) per World Health Organization standards; PMH was categorized into tertiles. Age adjusted PCVM rates (<65 years of age) were obtained from the CDC WONDER databases. County characteristics were sourced from County Health Rankings project. Using generalized linear mixed models with gamma distribution, we calculated rate ratios (RR). Results Among 315,720,938 residents lived in 3047 counties in 2013, 1,079,656 (0.34%) PCVM deaths recorded during study period (2013-2019). In the fully adjusted analyses*, high PM2.5 associated with elevated PMH (RR [95%CI]: 1.10 [1.08, 1.11], p<0.001]. In counties with high PM2.5 (≥10 µm2), PMH (T3 vs. T1) associated with a 3-fold increase in PCVM (RR: 1.15 [1.12, 1.18]) compared to low PM2.5 (1.05 [1.01, 1.08]), with p interaction <0.001. This trend persisted across PCVM subtypes (Figure1). Conclusion High PM2.5 worsens PMH, significantly amplifying the PCVM burden across the United States, beyond other social determinants of health. Targeted public health strategies must urgently address the interconnected pollution-mental health crisis to mitigate rising PCVM.