Abstracts

Rationale: Seizure clusters (SCs) are multiple, distinct seizures that occur over a 24-hour period. Each SC carries a risk of progression to prolonged seizures and status epilepticus (SE). Rescue medications are taken as needed to stop SCs; however limited data exist on the impact of inconsistent use of rescue medications on the clinical and economic outcomes associated with SC. To evaluate the association between use of rescue medications and the effects on clinical outcomes and healthcare resource utilization in epilepsy patients experiencing SCs, a chart review was undertaken.Methods: An online, retrospective chart review of epilepsy patients with SCs was conducted among 186 geographically diverse US-based neurologists. Adults (≥18 years of age) who were diagnosed with SCs at least 12 months prior to chart abstraction and experienced ≥1 SC within the 12 months prior to the abstraction were eligible. Demographics, comorbidities, and seizure-related medical information over a 12-month period were collected by neurologists using a web-based form. Patients were grouped by use of rescue medication: those who used for all clusters (Always Users), those who did not use for at least one episode (Sometimes Users), and those who never used (Never Users). Adherence was defined as use of a prescribed rescue medication to treat a SC, as reported in the chart abstraction form. Multivariable logistic regression models were used to compare SC-related outcomes and resource utilization between groups.Results: 528 complete patient charts were collected; the mean age was 41 years, and 308 (58%) were male. 363 (69%) Always Users, 82 (16%) Sometimes Users, and 83 (16%) Never Users were identified. On average, these patients experienced 2.4±10.7, 4.0±4.3, and 1.5±1.8 SCs, respectively, in the last 12 months before chart abstraction (Table 1). Sometimes Users were more likely to progress to SE (31% vs 15%, P<0.01) and had more SC-related emergency department (ED) visits (67% vs 45%, P<0.01) and inpatient (IP) admissions (46% vs 26%, P<0.01) compared to Always Users. Although Never Users experienced significantly less SCs, they were comparable with Always Users when examining progression to SE (17% vs 15%, P=0.75), ED visits (45% vs 45%, P=0.921), and IP admissions (34% vs 26%, P=0.134). These results remained consistent after adjusting for clinical characteristics including age, gender, living situation, comorbidities, seizure type, and years since SC diagnosis.Conclusions: In this study of epilepsy patients with SC, patients with an increased frequency of SC and who were non-adherent to rescue medication had more adverse clinical outcomes (SE) and greater healthcare resource use (ED and IP). These findings suggest that patient adherence to rescue medication may be associated with improved clinical outcomes and healthcare resource use. Supported by Acorda Therapeutics, Inc.