Stroke systems of care: evaluating disparities after stroke legislation implementation in Rhode Island.

INTRODUCTION: The Rhode Island Stroke Prevention and Treatment Act aimed to establish a standardised system of care for stroke patients through designated stroke centres, revise emergency medical services (EMS) protocols, and establish a centralised stroke database. While Stroke Systems of Care (SSOC) laws have proven effective in reducing overall stroke mortality, their benefits among racial minorities and economically disadvantaged groups remain unclear. This study investigates the impact of the Act and its amendment on stroke mortality rates across different racial groups. METHODS: Data from the Rhode Island Department of Labor and Training, Centers for Disease Control Atlas of Heart Disease and Stroke, and US Census Bureau for 2006-2019 were analysed. A linear regression model analysed mortality rates among White, Black and Hispanic residents before and after the Act's implementation. Trends were further validated using a segmented regression and mixed-effects model. RESULTS: Difference-in-differences analysis showed SSOC implementation reduced statewide all-stroke mortality by 8.56 deaths per 100 000 (95% CI -10.56 to -6.56; p<0.001). White and Hispanic groups declined, but the Black population diverged significantly from White (+20.80; 95% CI 4.83 to 36.77; p=0.011). Interrupted time series confirmed higher Black baseline mortality (β=9.70; 95% CI 2.00 to 17.40; p=0.014) and an abrupt post-implementation increase (β=29.14; 95% CI 16.64 to 41.63; p<0.001), followed by annual decline (β=-6.98; 95% CI -10.24 to -3.61; p<0.001). After amendment, Black mortality rose immediately (+19.80; 95% CI 2.15 to 37.44; p=0.028) and annually (+8.40; 95% CI 1.33 to 15.47; p=0.020). White and Hispanic groups showed no significant amendment-period changes. CONCLUSION: While SSOC significantly reduced overall stroke mortality in Rhode Island, the benefits were not equitably distributed across racial groups. These findings underscore the need for future stroke legislation to incorporate culturally competent, evidence-based strategies addressing social determinants of health to reduce disparities and ensure equitable care.