Defining Vascular Deserts to Describe Access to Care and Identify Sites for Targeted Limb Preservation Outreach

Abstract

Background: Access to care plays a critical role in limb salvage in chronic limb-threatening ischemia (CLTI). A "medical desert" describes a community lacking access to medical necessities, resulting in increased morbidity and mortality. We sought to describe vascular deserts, which we defined as regions with decreased access to specialty care.

Methods: All California providers performing vascular surgery procedures were identified through online provider and health care facility searches. Facility participation in the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) lower extremity bypass (LEB) and peripheral vascular intervention (PVI) modules was also determined. Addresses were geocoded with a 30-mile surrounding buffer using ArcGIS (Geographic information systems), creating maps based on care type, including all providers performing vascular procedures, board-certified vascular surgeons, and facilities participating in VQI modules. Public census data overlayed on the maps demonstrated population composition in desert versus nondesert regions. Subsequently, data from the Healthy Places Index (HPI) was overlayed, providing data regarding 25 social factors, comprising an overall HPI score and percent, with lower scores corresponding to poorer health and outcomes.

Results: Maps depicting care regions demonstrated decreased provider coverage with increasing specialty care, with the VQI provider map showing the most prominent "desert" regions. When comparing nondesert versus desert regions by care type, demographics including race, the percentage of the population 200% below the poverty line, and the rate of uninsured residents were described. Social determinants of health were then described for desert and nondesert regions by care type, including the HPI percentage and specific domain factors. The percentage of uninsured residents was significant only in the desert and nondesert areas served by board-certified vascular surgeons (19.6 vs. 16.8%, P < 0.001). The mean HPI percentile was significantly lower in board-certified provider and VQI facility deserts than nondeserts (50.48% vs. 40.65%, P < 0.001 and 52.68% vs. 43.12%, P < 0.001, respectively). The economic and education factor percentiles were significantly lower in all desert populations, while the housing, social, and pollution factors were significantly higher in nondesert regions. Health care access, transportation, and neighborhood factor percentiles were significantly lower in board-certified and VQI facility deserts than in the nondesert areas.

Conclusions: Access to vascular care plays a significant role in limb salvage. Through mapping vascular deserts, patient demographics, and social factors in desert regions are better understood, and areas that would benefit most from targeted outreach and limb preservation programs for CLTI are identified.