Abstracts

Rationale: Previous literature signals that comorbid depression in patients with epilepsy can lead to worsened outcomes, although the nature of this relationship remains unclear. This study evaluates health outcomes associated with comorbid depression in epilepsy. Methods: A cross-sectional survey was conducted of adult patients with epilepsy. Patients were identified from a large US health plan, and were required to have two or more diagnoses for epilepsy (ICD-9-CM 345.xx) or non-febrile convulsions (ICD-9-CM 780.3 or 780.39) on two separate dates of service as well as at least two pharmacy claims for AED medications on different dates of service. Data were collected on demographic and clinical characteristics, and validated measures of depression (CES-D and NDDI-E). Outcomes measured were seizure severity (SSQ) with higher scores associated with more severe seizure; quality of life (QOLIE-10) with higher scores associated with lower quality of life; cognitive function (MOS-COG) with higher scores associated with better cognition; and adverse events (Liverpool AEP) with higher scores associated with increased side effects; and medication adherence (Morisky and patient report). Cohorts were developed based on CES-D and NDDI-E scores: Cohort A (non-depressed for CES-D and NDDI-E); Cohort B (non-depressed CES-D and depressed NDDI-E); Cohort C (depressed CES-D and non-depressed NDDI-E); and Cohort D (depressed by CES-D and NDDI-E). All survey variables were analyzed descriptively. Results: Data were analyzed from 465 adult patients with epilepsy. Patients were 45% male, mean age of 44.77 years (SD 13.41), and 93% white. Overall, the CES-D categorized 36% as depressed and the NDDI-E identified 19% as depressed. Cohort A (n=291) consisted of patients identified as non-depressed and Cohort D (n=82) was comprised of patients categorized as depressed. For seizure severity, mean scores for Cohort A are 2.16 (SD 1.72) and Cohort D 3.42 (SD 1.45) (p=0.003). For quality of life, mean scores for Cohort A are 16.27 (SD 4.68) and for Cohort D are 27.46 (SD 7.02) (p<0.001). For cognition, mean scores for Cohort A are 83.37 (SD 17.92) and for Cohort D are 53.58 (SD 24.31) (p<0.001). For adverse events, mean scores for Cohort A are 30.24 (SD 8.63) and for Cohort D are 46.46 (SD 10.60) (p<0.001). When comparing Cohorts C (n=84) and D (n=82), significant differences were observed for specific adverse events of tiredness, feelings of aggression, nervousness/anxiety, concentration difficulty, shaky hands, weight gain, and depression (all, p<0.05). No significant differences were seen for adherence.