022 - Use of health care utilization heatmaps to inform statewide telehealth policy and expansion in South Carolina

Background:
Telehealth has long been touted for its promise to extend access to health care to those in rural and underserved communities. The exponential increase in telehealth utilization brought about by the pandemic has raised important policy considerations and are even more urgent as temporary policy provisions allowing telehealth during the public health emergency are soon to sunset. As we grapple with the future of telehealth and push for more equitable access to this modality, it is critical that the research community supply relevant, digestible data to facilitate informed decision and policy making. Applying various mapping techniques to claims data, telehealth administrative data, and social determinants of health data may prove helpful in speeding the data to telehealth policy pipeline.
The Medical University of South Carolina (MUSC)-one of two National Telehealth Centers of Excellence and the administrative headquarters for the state-funded South Carolina Telehealth Alliance (SCTA)-began using geographic heat mapping to inform its strategic planning and advocacy among policymakers. This year, three heat mapping methods were deployed to investigate a) gaps in access to outpatient specialty care in SC to inform targeted telehealth specialty services, b) hospital outmigration patterns to inform hospital-based telehealth consultative support to rural hospitals, and c) virtual urgent care (VUC) utilization among vulnerable populations to inform advocacy for payment by Medicaid.
Methods:
Outpatient Specialty Care: Using a 5% national Medicare data set from 2018-2019, E/M CPT codes were filtered by billing provider specialty and grouped by patient county. Specialty visit volumes per capita for each county were calculated, and counties were stratified to into quartiles for heat mapping based on county visit rates. Additionally, for the counties in the bottom 3 quartiles, the number of visits needed for each county to advance to the quartile above them was calculated and overlayed onto the county map. This helped visualize the scale of added telehealth specialty visits needed in each county to achieve more equitable access.
Hospital Outmigration: To visualize hospital outmigration, we analyzed the same 5% sample of Medicaid data, this time by inpatient specialty CPT codes and patient county to determine "demand" for inpatient specialty services per capita by county. This was then compared with HCUP hospital admission data during the same time period to determine county "supply" per capita. The difference between these numbers was calculated for each county, and this difference was used to place counties in quartiles to indicate levels of outmigration that might be mitigated by telehealth consultative support.
VUC Utilization: Finally, using MUSC's VUC database, MUSC calculated the rates of VUC encounters per capita by patient zip code. Zip codes were stratified into quartiles based on their rate and mapped. Utilization rate maps were then compared with zip code mapping of social vulnerability based on the CDC's social vulnerability index (SVI).
Results & Discussion: Heatmap results show low specialty care utilization and neuro admissions to local county hospitals among Medicare participants in rural counties in SC, particularly along the I-95 corridor which is a region known for low access to care and poorer health outcomes. Heatmaps of virtual urgent care visits per capita (that were free during COVID) within the large contiguous Charleston tri-county area in coastal SC show an inverse relationship to the areas with the lowest social vulnerability. This trend of low utilization among the most vulnerable population was also found in a New York study. Simple but powerful data driven methods are needed to ensure state policymakers understand and support efforts to reach the most vulnerable populations in order to realize the promise of increased access using telehealth particularly in rural and underserved states.

telehealth, telemedicine, virtual care

mapping

data visualization

health equity

public health

health policy 

Beginner

Influence

International Conference on Health Policy Statistics 2023