Abstract Body (Do not enter title and authors here): Background: Environmental contributors to sudden death are not well understood but should inform emergency preparedness and mitigation strategies. We examined flood and pollution risk and sudden death from 2018 to 2021 in Lenoir, a rural North Carolina County which suffered extensive damage from recent hurricanes, most notably Hurricane Matthew in 2016.

Research Aim: Determine if census tracts with greater flood or pollution risk have higher sudden death rates.

Methods: We identified sudden deaths among adults aged 18-64 from death certificates using a published algorithm (Figure 1). We geocoded decedents’ addresses and linked them to census tract-level data from the EPA Climate and Economic Justice Screening Tool and American Community Survey. Flood risk was defined as the percentage of census tract residents at high (>25%) flood risk over the next 30 years, and pollution risk as the percentage of residents ≤1 mile from a Toxic Release Inventory site. We compared census tract-level sudden death rates by flood and pollution risk levels using incidence rate ratios (IRRs) estimated with Poisson regression, adjusted for racial distribution, median household income, and prevalence of coronary heart disease, diabetes, and hypertension.

Results: Among the 15 census tracts in the county, the median flood risk was 10% (range 4 to 16), and the median pollution risk was 8.4% (range 0 to 56.54). Of the 15 tracts, 2 were in the highest tertile for both flood and pollution risk. There were 242 sudden deaths in Lenoir County during the study period, a rate of 437 per 100,000. Tract-level sudden death rates ranged from 246 to 1,130 per 100,000 (Figure 2). Every increase of 10 percentage points in flood risk was associated with a 92% increase in sudden death rates (IRR 1.92, 95 % CI 1.40–2.64). Every 10-point increase in pollution risk was associated with a 14% increase in sudden death (IRR 1.14, 95 % CI 1.04–1.23) (Table 1). Being in the highest risk tertiles for both flood and pollution was associated with higher sudden death rates compared to being in the lowest tertiles for both (IRR 2.02, 95% CI 1.50-2.66).

Conclusions: Flood and industrial pollution risk were associated with higher sudden death rates within a rural county, even after accounting for socioeconomic and cardiometabolic burden. Locally-targeted environmental hazard preparedness and mitigation should be evaluated to prevent sudden deaths in vulnerable communities.