Abstract TP133: Impact of Proximity to Certified Stroke Centers on Stroke Outcomes and Risk Profiles in the United States

Geographic disparity in stroke is well researched, with consensus being that greater distance from a certified stroke center (SC) is associated with worse outcomes. The extent to which geographic access interacts with other stroke risk factors remains unclear. This study investigates the impact of SC proximity on various comorbidity risk factors and stroke outcomes across the United States. This study analyzed 3,068 U.S. counties and 2,460 certified SCs. Data from the CDC Atlas of Heart Disease and Stroke and EMNet’s findERnow database informed this study. Metrics included distance from the center of a county to the nearest SC, stroke prevalence and mortality (per 100,000 people), comorbidity, and health utilization rates. Gamma regression was used to analyze across continuous distance and ordinal regression was used for categorized ranges. Both ischemic (RR 0.90, 95% CI [0.89, 0.92]; P<0.001) and hemorrhagic (RR 0.45, 95% CI [0.40, 0.51]; P<0.001) stroke prevalence were negatively associated with distance from a certified SC. Increased distance from a certified SC was positively correlated with coronary heart disease prevalence (OR 2.05, 95% CI [1.71, 2.46]; P<0.001) and negatively correlated with smoking prevalence (OR 0.93, 95% CI [0.90, 0.99]; P<0.001). Stroke prevalence for the total population was higher in counties with higher rates of obesity (RR 1.01, 95% CI [1.00, 1.02]; P=0.003), smoking (RR 4.04, 95% CI [2.50, 6.55]; P<0.001), and hypercholesterolemia (RR 3.12, 95%CI [1.80, 5.40]; P<0.001). Counties with high rates of regular cholesterol screening had decreased mortality from stroke (RR 0.98, 95% CI [0.97, 0.98]; P<0.001). These counties had no association with range from nearest SC (OR 0.97, 95% CI [0.92, 1.02]; P=0.214). Mortality rates for ischemic (RR 0.99, 95% CI [0.99,0.99]; P<0.001) but not hemorrhagic (RR 1.00, 95% CI [0.99, 1.00]; P=0.268) stroke were significantly correlated with SC distance. When stratifying for race, only Native American populations demonstrated higher mortality with increased SC distance (OR 1.14, 95% CI [1.03, 1.25]; P=0.009). Certain groups may face a higher mortality burden from stroke regardless of proximity to certified SCs. This could be due to lack of access to health screening and increased chronic disease burden, leading to more severe presentations to the hospital. Efforts to reduce stroke disparities should focus on prevention and access to care beyond geographic proximity to certified stroke centers.