Date of Award
Doctor of Philosophy (PhD)
Applied Health Research and Evaluation
Corey A. Kalbaugh
Peripheral artery disease (PAD) is a progressive circulatory disorder of the lower extremities that occurs when atherosclerotic plaques obstruct arteries carrying blood from the heart to the legs. PAD is associated with reduced quality of life and increased risk of poor outcomes, particularly among disadvantaged groups. There is a need to better understand disparities experienced by disadvantaged groups. Thus, the purpose of this doctoral research was to explore the association of geographic, economic, and socio-demographic factors with PAD. South Carolina is an ideal location to investigate disparities of PAD due to the risk profile of South Carolina residents and the availability of a robust repository of all payor health care data.
Unplanned hospital readmissions among patients with PAD are associated with serious complications, increased mortality, and high costs. We found adjusted readmission rates for patients with PAD ranged from 35.3 per 1000 to 370.7 per 1000 patients with PAD and the risk of readmission was significantly associated with the proportion of patients with PAD who are younger, have Medicare, and have hypertension. Our spatial model identified significant geographic variation in readmission rates throughout South Carolina as well as clusters of high rates of readmissions.
Individuals with PAD incur higher health care-related expenditures than those without PAD but little is known about PAD-costs differences between insurance providers. Our study found that length of stay, and total charge varied significantly by insurance provider. Medicare and Medicaid patients both had longer length of stays than patients with private insurance. However, Medicare patients had higher total charges than patients with private insurance, while Medicaid patients had lower total charges.
Socioeconomic factors have been shown to be associated with amputation in PAD; however, analyses have typically focused on individual-level measures of socioeconomic status and not community-level measures. After controlling for death and adjusting for demographic and medical covariates, we found an increased hazard of amputation among individuals in a distressed community, which persisted across racial strata. Notably, Black individuals having higher incidence of amputation, regardless of the community distress level.
Witrick, Brian A., "Advanced Epidemiologic Methods to Estimate Disparities in Peripheral Artery Disease in South Carolina by Geographic Location, Payor Status, and Socio-Demographics" (2022). All Dissertations. 3053.
Author ORCID Identifier
Available for download on Saturday, April 08, 2023