Abstracts

Rationale: The Human Epilepsy Project (HEP) is a prospective, observational study whose primary goal is to identify clinical characteristics and biomarkers predictive of disease treatment response, progression, and outcome in participants with newly treated focal epilepsy. As part of this larger investigation, cognitive data are collected to determine if they are predictive of treatment outcome, and to delineate the adverse cognitive effects of antiepileptic drug (AED) treatment and ongoing seizures. Multiple factors can contribute to cognitive impairments in people with epilepsy. When studied together with other patient and disease variables, it may be possible to leverage information regarding baseline cognitive impairments to better predict disease factors (e.g., refractory seizures). The aim of this report was to assess the proportion of patients with newly treated focal epilepsy that have cognitive impairments.Methods: Patients with epilepsy enrolled in the HEP study underwent cognitive testing with Cogstate, a battery of computerized tests available online that assesses functions such as attention, memory, and processing speed. The Cogstate battery has been shown to be sensitive to disease and drug effects. Participants in HEP completed the tests following the enrollment visit and every 3 months thereafter for the duration of their participation. The tasks included: Detection (DET), Identification (IDN), One Back Memory (ONB), One Card Learning (OCL), and Groton Maze Learning (GML). Outcomes variables included speed for DET, IDN and ONB; accuracy for OCL; and total errors for the GML. The normed scores were reviewed to determine the percentage of patients with low scores (i.e., <1 SD from healthy controls) for each test and for two or more tests in the battery at enrollment.Results: 176 patients have undergone cognitive testing at enrollment. Patients with impaired scores for each test relative to healthy controls were as follows: DET=26%, IDN=18%, ONB=27%, OCL=37%, AND GML=20%. Impairment on two or more tests in the battery was found in 36% of the population. In comparison, 15% of the normative sample would be expected to fall below 1 SD.Conclusions: The findings indicate that there are cognitive impairments in a sizable portion of patients with newly treated focal epilepsy. Future analyses with follow-up data will determine if these impairments are related to task familiarity or are predictive of treatment outcome and/or adverse cognitive effects of AED treatment and ongoing seizures. Sources of funding: The Epilepsy Study Consortium (ESCI) is a non-profit organization dedicated to accelerating the development of new therapies in epilepsy to improve patient care. The funding provided to ESCI to support HEP comes from industry, philanthropy and foundations (UCB Pharma, Finding A Cure for Epilepsy and Seizures, Pfizer, Lundbeck, The Andrews Foundation, Friends of Faces and others).