Abstract 4138321: Marine Microplastic Levels and the Prevalence of Cardio-Metabolic Diseases in Coastline Counties: An Ecological Analysis

Background: Micro- and nanoplastics are an emerging risk factor for the development of cardiovascular diseases. The association of marine microplastic levels (MMLs) with the burden of cardiometabolic diseases at a population level remains unexplored. Aim: To investigate the association between the average microplastic concentration in the ocean water body within 200 nautical miles of US coastline surveyed between 2015 and 2020, assigned to its most adjacent coastline county, and the prevalence of type 2 diabetes (T2D), coronary artery disease (CAD), and stroke in those counties. Methods: Microplastic concentration data within 200 nautical miles of the US coastline was spatially analyzed in ArcGIS Online to calculate mean MMLs. The coastal counties were stratified into four categories based on MMLs in the adjacent ocean water body: low (0-0.005 pieces/m 3 ), medium (0.005-1 pieces/m 3 ), high (1-10 pieces/m 3 ), or very high (≥10 pieces/m 3 ). BRFSS 2019-2020 survey data was used to correlate with the prevalence of type 2 diabetes (T2D), coronary artery disease (CAD), and stroke in these counties. Univariate and population-weighted multivariate quasi-Poisson regression adjusted for median county age, sex, physician access, and baseline community vulnerability theme of the US climate vulnerability index (CVI) was used to evaluate unadjusted and adjusted associations between disease prevalence and MMLs. Results: The mean age of the population was 43 ± 6 years. The mean prevalence of T2D, CAD, and stroke was significantly higher in counties with very high MMLs (13.03%, 8.94%, and 4.17%, respectively) compared to low MMLs (11.23%, 7.43%, and 3.51%, respectively, p < 0.001). The counties with very high MMLs exhibited an 18% higher adjusted prevalence of T2D (PR: 1.18 [1.13 – 1.23], p < 0.001), 7% higher adjusted prevalence of CAD (PR: 1.07, [1.03 – 1.11], p < 0.001), and 9% higher adjusted prevalence of stroke (PR: 1.09, 95% CI: 1.05 – 1.13, p < 0.001) compared to those with low levels. Conclusion: Our study establishes a significant association between marine microplastic levels and cardiometabolic disease prevalence in coastal counties.