Abstracts

Rationale: Depression is a common comorbid disorder in people with epilepsy and studies have suggested multiple sociodemographic and clinical factors that may be associated with the development of depression in a person with epilepsy. Recent studies have addressed this topic by looking at community samples and larger, more representative national populations. This case-control study examines a population of outpatients with epilepsy being served at the University of Washington Regional Epilepsy Center and affiliated neurology clinics. Methods: Project PEARL (Program for Encouraging Active, Rewarding Lives) is a CDC-funded randomized controlled trial studying an in-home intervention for patients with epilepsy and depression. PEARL has recruited 80 subjects to date through a screening process using the Patient Health Questionnaire-9 (PHQ-9). To complete the case-control study, 359 subjects who were screened for PEARL but found to be not depressed were sent questionnaires containing the same sociodemographic and clinical questions asked of the 80 PEARL trial subjects at baseline. A total of 185 subjects (55%) responded and 141 were able to serve as controls. Bivariate analyses were completed for all sociodemographic and clinical data. A logistic regression model was created using the unadjusted variables significantly associated with depression in the bivariate analyses (p<0.05). Results: In bivariate analyses, compared to non-depressed subjects, depressed subjects were significantly more likely to be unmarried, unemployed, less educated, less physically active, and to report more medical problems. Depressed subjects were significantly more likely than non-depressed subjects to report any type of seizure (with or without loss of consciousness) in the prior month or six months. Depressed subjects were significantly more likely to be using benzodiazepines, antidepressants, and not to be taking lamotrigine. In the multivariate logistic regression analysis, the odds of being depressed were significantly higher for subjects with epilepsy that were unmarried, unemployed, and reporting any medical problems. Subjects reporting any seizures with loss of consciousness in the prior six months were more likely to be depressed compared to subjects reporting no seizures [OR 5.7 (95% CI: 2.5 - 12.8)]. Subjects reporting any seizures without loss of consciousness in the prior six months were more likely to be depressed compared to subjects reporting no seizures [OR 2.2 (95% CI: 1.1 - 4.7)]. Adjusting for all other variables, subjects with epilepsy reporting lamotrigine use were less likely to be depressed compared to those not reporting lamotrigine use [OR 0.4 (95% CI: 0.2 - 0.8)]. Conclusions: This case-control study supports other evidence indicating that patients with epilepsy and other comorbid medical problems as well as breakthrough seizures are at risk for developing depression. In addition, it adds to the growing evidence suggesting that lamotrigine treatment in a patient with epilepsy may prevent or treat depression.