Increased BDNF levels after electroconvulsive therapy in patients with major depressive disorder: A meta-analysis study

Objective: We performed a systematic review and meta-analysis to estimate brain-derived neurotrophic factor (BDNF) level in patients with major depressive disorder (MDD) after electroconvulsive therapy (ECT). Method: A comprehensive search of the Cochrane Library, MEDLINE, LILACS, Grey literature, and EMBASE was performed for papers published from January 1990 to April 2016. The following key terms were searched: major depressive disorder, unipolar depression, brain-derived neurotrophic factor, and electroconvulsive therapy. Results: A total of 252 citations were identified by the search strategy, and nine studies met the inclusion criteria of the meta-analysis. BDNF levels were increased among patients with MDD after Ecr (P value = 0.006). The standardized mean difference was 0.56 (95% CI: 0.17-0.96). Additionally, we found significant heterogeneity between studies (I-2 = 73%). Conclusion: Our findings suggest a potential role of BDNF as a marker of treatment response after Ecr in patients with MDD. (C) 2016 Elsevier Ltd. All rights reserved.