County-Level Geographic Access and Cardiovascular Disease Outcomes in Washington State.

BACKGROUND

Geographic access to specialized cardiac care varies widely, yet how these disparities relate to population-level cardiovascular disease (CVD) outcomes remains poorly understood.

OBJECTIVES

The objective of the study was to evaluate county-level disparities in geographic access to specialized cardiac care and their associations with CVD prevalence, hospitalization, and mortality across Washington state.

METHODS

We assessed county-level variation in average travel time and distance to facilities offering catheterization laboratory, coronary intervention, cardiac surgery, and emergency services across all 39 Washington state counties using publicly available data and the Google Maps API. Reliance on critical access hospitals (CAHs) was also evaluated. Age-adjusted CVD prevalence, mortality, and hospitalization rates were obtained from the CDC Atlas of Heart Disease and Stroke (2019-2021) and multivariable linear regression were used to assess associations between county-level accessibility metrics and CVD outcomes.

RESULTS

In adjusted univariable analyses, shorter travel time and distance to catheterization laboratories, coronary intervention, and cardiac surgery facilities were associated with higher cardiovascular and heart disease hospitalization rates (R2 = 0.34-0.50, all adjusted P < 0.05). Conversely, greater rurality and longer travel burden to these specialized cardiac services were associated with higher prevalence of coronary heart disease, hypertension, and stroke (R2 = 0.35-0.56; all adjusted P < 0.05). No county-level predictor was associated with overall heart disease prevalence. For mortality, higher area deprivation index and lower median household income were the only significant predictors, each associated with higher ischemic stroke mortality (R2 = 0.41-0.43; both adjusted P < 0.01). In multivariable analyses, travel burden remained independently associated with hospitalization but not with prevalence or mortality after adjustment for area deprivation, rurality, and age structure. CAH-reliant counties had lower hospitalization rates but higher CVD prevalence compared with non-CAH-reliant counties (all P < 0.05).

CONCLUSIONS

Greater travel burden to specialized cardiac care was associated with higher CVD prevalence and lower hospitalization but not mortality. Socioeconomic factors most strongly predicted CVD mortality, suggesting that reducing geographic disparities requires addressing both care access and socioeconomic determinants.