Abstracts

Rationale: Outside of a modest relative increase for racial minorities in the United States (US), the incidence and prevalence of the epilepsies are considered to be racially indiscriminant. Little is known, however, about distribution of prevalence for epilepsy subtypes between Caucasians and other races. The Southeastern US has a relatively large African American minority population. This study exploited the large volume of patients diagnosed with various epilepsies in the University of Alabama at Birmingham (UAB) Seizure Monitoring Unit (SMU) to examine perceived differences in epilepsy prevalence between African-Americans and Caucasians.Methods: This study reviewed all admissions to the UAB SMU between 1998 and 2010. Primary epilepsy diagnoses were determined at the end of the evaluations based on history, exam, interictal EEG, and ictal EEG plus semiology (when seizures were captured). A total of 4567 admissions were examined. The population was 78% Caucasian, 19% African-American, and 3% other. The median age was 36 years (3043 females and 1684 males). Only prevalence measures of African-Americans (n=687) and Caucasians (n=2926) were compared. The database did not include diagnoses for 953 cases, but the within race percentage of cases in this group were equal between African-Americans and Caucasians. Prevalence for each of the following diagnostic groups was measured: temporal lobe epilepsy, extratemporal lobe epilepsy, generalized epilepsy, mixed or indeterminate epilepsy, non-diagnostic study, or psychogenic non-epileptic seizures.Results: See table for prevalence measures of each diagnostic classification for African-Americans and Caucasians. Patients represented all 67 counties in Alabama. In spite of few access barriers to the UAB SMU (all patients are cared for even those without medical insurance) African-American patients were under represented in this population 19% versus the expected demographic representation of 26% in Alabama. Females were also disproportionately represented in both races 2.1:1 for African Americans and 1.7:1 for Caucasians. Relative prevalence between African-Americans and Caucasians was remarkably similar for all epilepsies and remaining diagnostic categories except for temporal lobe epilepsy (statistically significantly greater in African Americans at the 95% confidence level).Conclusions: In this large, mostly adult, population with well-defined epilepsy diagnoses based on seizure monitoring, a disproportionate prevalence specific for temporal lobe epilepsy is identified in Southeastern US African Americans. Most of this relative increase in prevalence is carried by African American females, but the under representation by males in this population limits interpretation of a gender effect.