Abstract WP149: Mid-2010s Reversal in U.S. Stroke–Diabetes Mellitus Co-Mortality: Geographic and Demographic Disparities in National Trends, 1999–2020

Background: Stroke and diabetes mellitus share causes, making co-mortality a key risk marker. After decades of gains, U.S. progress plateaued in the mid-2010s as risk-factor control faltered and stroke declines reversed, exposing disparities by ethnicity, region, rurality, race, and sex. Objective: To evaluate national trends in stroke–diabetes co-mortality in the U.S. from 1999–2020, with emphasis on geographic and demographic disparities. Methods: We analyzed U.S. death certificates from CDC WONDER (1999–2020), defining stroke as the underlying cause (ICD-10: I60–I64, I69.0–I69.4) and diabetes as the contributing cause (E10–E14). Age-adjusted mortality rates (AAMRs), per 100,000, were calculated and stratified by sex, race, ethnicity, Census region, and urbanization. Trends were assessed with Joinpoint regression, estimating annual percent changes (APCs). Results: From 1999–2020, 222,658 stroke–diabetes deaths were identified. Nationwide, AAMR declined from 4.3 in 1999 to 2.7 in 2020, with a steep fall until the mid-2010s followed by a reversal. Hispanics had a higher mean AAMR (3.8) than non-Hispanics (3.1). Regional variation was marked, with the South (3.5) and West (3.4) exceeding the Midwest (3.0) and Northeast (2.4); post-2014 increases were concentrated in the South/West. Non-metropolitan areas had higher mean AAMRs (3.6) than metropolitan areas (3.0), with the sharpest resurgence after 2015 in rural settings. By race, Black/African Americans had the highest mean AAMR (5.6), Whites the lowest (2.7), while American Indians/Alaska Natives declined steadily, and Asians/Pacific Islanders reversed upward post-2015. By sex, men consistently had higher mean AAMRs (3.3) than women (2.8). Conclusions: Stroke–diabetes co-mortality in the U.S. shows a mid-2010s reversal, with Hispanic/Latino, Southern/Western, and rural groups most affected. These trends reflect faltering control of blood pressure and diabetes, unequal access to stroke-ready care, and a 2020 pandemic spike. Priorities include tighter control of hemoglobin A1c, blood pressure, and LDL cholesterol: optimized statin use; screening for nonalcoholic fatty liver disease (NAFLD) in diabetes care; and expanded rural access to intravenous thrombolysis and endovascular thrombectomy.