Abstracts

Rationale: There are few validated measures to evaluate humanistic outcomes in epilepsy and none which meet the guidance recently released by the FDA. We developed a patient-reported outcome (PRO) measure intended to be sensitive to changes in functional status and suitable for daily administration in clinical trials of new medications for epilepsy. Methods: The Functional Status Diary (FSD) for epilepsy was developed in accordance with the FDA PRO guidance, including the involvement of patients throughout the process. We used a two phase development process with the first phase presented here. Epilepsy specialists provided clinical input. Patient focus groups were recruited and conducted that targeted newly treated and drug resistant (refractory) patients with partial-onset seizures. Patients were asked to describe all aspects of functioning impacted by their epilepsy and to identify functional improvements anticipated with a significant reduction in seizure frequency. Based on the focus group results, items were drafted and refined through two iterative sets of cognitive debriefing interviews conducted with 17 additional patients. Results: Seven focus groups (n=46) were conducted in three geographic locations. Seventy percent of the patients were white, 59% were female, and the average age was 36 years (range 19-65 years); 19 were diagnosed with depression, and 9 with anxiety. All patients reported considerable impact from epilepsy. Specific constructs associated with an anticipated 50% reduction in seizures included increased independence; reduced worry; ability to do more in work, family, and social activities; reduced emotional fluctuations; more energy; better self-esteem; and improved short-term memory. Among these constructs, we selected those which would be mutable within the duration of a trial; could be collected daily along with seizure diary data, and were consistently identified by patients. Three items meeting these criteria were selected for inclusion in the FSD: 1) How would you rate your epilepsy-related worry? 2) How would you rate the extent to which epilepsy limited your ability to do what you needed to do? 3) How would you rate the extent to which epilepsy limited your ability to do what you wanted to do? Each item utilizes a 24-hour recall period and a 0-10 numeric rating response scale. Patients in debriefing interviews agreed that these items were highly relevant and easy to understand. Conclusions: This FSD addresses functional impacts which are applicable across a broad spectrum of patients with partial-onset seizures despite significant heterogeneity in this patient population. The second phase of development of the FSD will evaluate its psychometric properties and association with seizure frequency in a clinical trial.