County‐Level Contributors to Geographic Variation in Medicare Fee‐for‐Service Stroke Hospitalization Rates: A Cross‐Sectional Study

BACKGROUND: Stroke hospitalization represents underlying stroke incidence and hospital utilization. We sought to identify factors associated with county-level hospitalization rates (HRs) and counties with HRs above or below expectation using publicly available data. METHODS: , the most impactful factors, and characterized proportional difference between crude and predicted HRs. RESULTS: =0.57). The most impactful factors associated with stroke HRs were prevalence of coronary heart disease, hypertension, smoking, nonadherence to antihypertensive medication, and elevation above sea level. Counties in the northwest United States generally had lower-than-expected HRs. CONCLUSIONS: Considerable unexplained county-level variance in stroke HRs exists after accounting for a wide variety of known and potential predictors. Future work to clarify the mechanism of known predictors and explain variance may inform interventions to improve systems of care.