Greater Physician Supply Associated with Lower Mortality in Rural Counties: A 23-Year County-Level Longitudinal Observational Study.

Rural U.S. residents face higher mortality rates and reduced access to primary care physicians. Prior studies report mixed findings on physician supply and health outcomes, and few have examined whether increasing supply reduces rural-urban mortality disparities. The objective was to quantify the marginal benefits of additional primary care physician supply in rural and urban areas, independent of other healthcare and socioeconomic factors. We conducted a 23-year county-level longitudinal observational study of 2942 U.S. counties (1992-2014). Mortality rates were obtained from CDC WONDER, physician supply and socioeconomic characteristics from the Area Health Resource File, and rural-urban classification from the USDA's 2013 Rural-Urban Continuum Codes. We estimated regressions of age-adjusted mortality rates as a function of physician supply, rurality, and county-level characteristics. Despite the higher per-capita supply of hospital beds and post-acute care services in rural areas, physician supply was lower and grow more slowly than in urban areas. County-level analysis showed a negative association between physician supply and mortality. In rural counties, greater physician supply was associated with lower mortality rate; an increase of 1 physician was associated with 1.4 (CI: -1.963 to -0.836) and 0.936 (CI: -1.411 to -0.462) fewer deaths per 100 k population of older adults in rural counties adjacent and non-adjacent respectively, compared to 0.038 fewer deaths per 100 k population of older adults in urban areas. The declining physicians supply in areas where the number of physicians is already low is an alarming problem for rural communities. Efforts by policymakers to broaden rural health networks and increase rural medical personnel may be needed to address disparities in access to care and associated mortality outcomes. Although the dataset covers 1992 to 2014, the findings remain highly relevant given the continued rural physician shortages and widening mortality disparities that persist across the United States.