Risk factors for depression in community-treated epilepsy: Systematic review

Abstract Objective Depression is one of the most common psychiatric comorbidities in epilepsy; however, the factors contributing to this association remain unclear. There is a growing consensus that methodological limitations, particularly selection bias, affect many of the original studies. A systematic review focussed on community-based studies offers an alternative approach for the identification of the risk factors for depression. Methods Searches were performed in MEDLINE (Ovid), 2000 to 31 December 2013, EMBASE, and Google Scholar to identify studies examining risk factors for depression in epilepsy. Community-based studies of adults with epilepsy that reported at least one risk factor for depression were included. Results The search identified 17 studies that met selection criteria, representing a combined total of 12,212 people with epilepsy with a mean sample size of 718. The most consistent risk factors for depression were sociodemographic factors, despite the fact that most studies focus on epilepsy-related factors. Significance Most studies lacked a systematic conceptual approach to investigating depression, and few risk factors were consistently well studied. Future community-based studies require a detailed systematic approach to improve the ability to detect risk factors for depression in epilepsy. Psychological factors were rarely studied in community-based samples with epilepsy, although the consistent association with depression in the few studies that did suggests this warrants further examination.