Alzheimer's Disease and Related Disorders Prevalence Differs by Appalachian Residence in Ohio.

Abstract

Areas within the Appalachian region may have a greater burden of under diagnosed Alzheimer's disease and related disorders (ADRD). To estimate the prevalence of ADRD in the Appalachian counties of Ohio, and to determine if differences exist by geographic location (Appalachian/non-Appalachian and rural/urban) and across time among Medicare beneficiaries. Centers for Medicare and Medicaid Services Public Use Files from 2007-2017 were used to estimate county-level ADRD prevalence among all fee-for-service beneficiaries in Ohio. Negative binomial regression was used to estimate prevalence overall, by Appalachian Regional Commission's Appalachian/non-Appalachian designation, and by rural/urban (Rural-Urban Continuum Codes) classification. Models were repeated, adjusting for county-level demographics and comorbidities. The prevalence of ADRD varied by both Appalachian residence and rural status (p = 0.008). Before adjustment by county-level demographics and comorbidities, the prevalence of ADRD in urban Appalachian counties was 1-3% lower than in urban non-Appalachian counties, while rural Appalachian counties had 2-3% higher prevalence compared to rural non-Appalachian counties. After adjustment, the differences between prevalence ratios were accentuated; the prevalence ratio was consistently higher for rural Appalachian counties, yet varied across the study period for urban counties (1.03 in 2007 to 0.97 in 2017). The results suggest a disparate burden of ADRD in Ohio with higher prevalence in rural Appalachian counties. This potential difference by Appalachian region is important to consider for availability of services and subsequent delivery of care. In order to better understand the disparity, further epidemiologic studies are necessary to better estimate the burden of ADRD.