Mapping Healthcare Financial Burden: County-Level Out-of-Pocket Spending in the U.S.

Introduction: Out-of-pocket healthcare costs can be associated with a substantial financial burden, particularly when considered relative to local income. Although prior work has characterized geographic variation in healthcare spending, less is known about how out-of-pocket spending relates to local economic capacity. Methods: This is a longitudinal ecologic county-level analysis of out-of-pocket healthcare spending relative to per capita income across the U.S. from 2010 to 2019. All-ages county-level per capita mean out-of-pocket spending estimates were obtained from the Institute for Health Metrics and Evaluation, and county-level per capita personal income was obtained from the Bureau of Economic Analysis. The ratio of out-of-pocket spending to per capita income was calculated as a measure of population-level healthcare financial burden. National trends were summarized using population-weighted medians and IQRs. Change over time was quantified through estimated annual percentage changes. Results: Among 3,085 U.S. counties with available data, the national median out-of-pocket-to-income ratio declined from 2.09% (IQR=1.82–2.49) in 2010 to 1.57% (IQR=1.37–1.84) in 2019, corresponding to an estimated annual percentage change of −2.61% (95% CI= −3.02, −2.23). Although most counties experienced a decreasing burden, clusters of increasing out-of-pocket burden were observed, including in parts of New York, West Virginia, and the Upper Midwest. Conclusions: Although the population-level out-of-pocket healthcare burden declined nationally over the past decade, this improvement was uneven across counties. Integrating out-of-pocket spending with local income reveals substate hotspots of financial burden that may be obscured by broader geographic averages, providing a scalable framework to inform geographically targeted health system planning and policy evaluation.