Abstracts

Rationale: People with epilepsy (PWE) have a higher risk of mortality than the general population, because of disparities in the receipt of appropriate epilepsy care, which may be affected by socioeconomic status, race/ethnicity and insurance coverage. Increased epilepsy prevalence has been associated with black race, low educational attainment, unemployment, and low income levels. Rural/urban residence may affect health through individual (no routine source of care,) or environmental (poverty, income inequality, physical access to care, health care shortages) factors. Health disparities seen in rural residents are likely amplified in rural PWE because of limited access to specialized care. While rural/urban mortality differences among PWE have been described, it is not known if geographic location has a differential effect by race/ethnicity. This analysis aims to examine the risk of mortality attributable to race/ethnicity and rural residence in the statewide population of South Carolina (SC) after adjusting for potential confounders.Methods: This statewide, retrospective cohort study of PWE seen in SC non-federal hospitals and emergency departments from 2000-2013 describes the hazard of mortality by race/ethnicity and rural/urban residential status in addition to other demographic and clinical characteristics. Differences in proportions were assessed by comparison of 95% confidence intervals. The association of race/ethnicity and rural/urban residence with mortality was further evaluated with Cox proportional hazard regression controlling for demographic and clinical covariables.Results: 87,452 PWE were identified, of whom 24,017 (27.5%) had died. Deceased PWE were more likely to be rural residents, black, male, older, live in an area with a median income of $36,000 to $54,000, be covered by Medicare, have 5 or more common comorbidities of epilepsy and have an epilepsy or seizure diagnosis in at least 50% of their annual average visits. After adjustment for all other covariables, the risk of mortality did not differ by rural/urban residence but was higher in black PWE (HR=1.15; 95% CI=1.12,1.18) but not significantly different for PWE of other races compared with white PWE. Male PWE had higher hazard as did Medicare, Medicaid or commercially insured PWE, those living in zip codes with annual median incomes less than $36,000, and those with 2 or more comorbid conditions.Conclusions: While other covariables were more strongly associated with mortality after adjustment (older age, insurance coverage, income level of zip code, and number of comorbidities), the finding of a higher hazard in black PWE than white PWE after adjustment for other demographic and clinical covariables is cause for concern.