Abstracts

Rationale: Mental illness rates are disproportionately high in those with epilepsy and psychiatric conditions may lower seizure threshold or increase risk of treatment resistance. Understanding how psychiatric comorbidity affects crisis-based health resource use could help inform care approaches that minimize epilepsy burden. To better understand effects of psychiatric comorbidity on epilepsy we conducted a 5-year retrospective analysis from a large safety-net healthcare network and compared the occurrence of negative health events (NHEs), defined as emergency department (ED) visits and hospitalizations, among individuals with epilepsy and mental illness (E-MI) vs. those with epilepsy alone (E).Methods: Electronic health record (EHR) data from a large Midwestern U.S. safety net healthcare system were queried to identify a study population of adults ≥ 18 years with a diagnosis of epilepsy, with or without mental illness. We assessed demographic and clinical characteristics for each of the 5 years, and compared NHEs between subgroups with E-MI vs. E. An additional analysis focused on individuals who remained in the healthcare system over the entire 5-year study time-frame. NHE counts and hospital length of stay for individuals with E-MI and E were assessed, as were hospital discharge diagnoses.Results: The number (approximately 2,000) and characteristics of individuals for each year of the study period was relatively consistent. In 2014, mean age of individuals with epilepsy was 48 (range 18-95), 48.5% women, 51.1% White, 38.2% African-American, and 8.6% Hispanic. There were 1599 (78.9%) individuals in the E subgroup and 428 (21.1 %) in the E-MI subgroup. Most variables between the E-MI and E subgroups were similar, except that E-MI individuals were less likely to be employed or commercially insured. Overall, NHEs were common, with nearly 1/3 (30.1%) of all individuals with epilepsy having an ED visit during the year, 13.4% hospitalized and 37.8% had either an ED visit or hospitalization. Individuals with E-MI had significantly more NHEs compared to individuals with epilepsy only, as evidenced by higher rates of any NHE (p< .001), ED visits (p < .001) and hospitalizations (p<.001). For the 981 individuals who remained in the health system over the entire 5 year period, the cumulative differential in ED and hospital use between E-MI and E subgroups was substantial. Most NHEs were directly related to seizures for the group overall, while substance-use complications appeared as a top reason for hospitalization only in the E-MI group.Conclusions: Individuals with E-MI made up just over 20% of all people with epilepsy in a safety-net system and had higher rates of NHEs than those without mental illness. Better and earlier identification of individuals with E-MI and assistance with self-management that includes helping individuals to optimize care in ambulatory care settings as opposed to the ED and including treatment for substance use disorders could eventually reduce NHEs in this vulnerable subgroup of individuals with epilepsy.