Plasma brain-derived neurotrophic factor (BDNF) concentration and the BDNF Val66Met polymorphism in suicide: a prospective study in patients with depressive disorder

PURPOSE: The relationship was investigated between brain-derived neurotrophic factor (BDNF) concentrations, a BDNF polymorphism (196G>A), and the response to selective serotonin reuptake inhibitors (SSRIs) among Chinese patients with major depressive disorder (MDD). PATIENTS AND METHODS: A total of 125 patients and 91 healthy controls were enrolled. The disease progression and treatment responses were evaluated using the Hamilton depression rating scale (HAMD24), the Hamilton anxiety scale, the Beck depression index, and BDNF concentrations at the baseline, 4, 8, and 12 weeks after treatment. Responders were defined as patients with at least a 50% decrease in the HAMD24. RESULTS: The BDNF concentrations were significantly lower in MDD (947±297 vs 1187±236 pg/mL, p=0.019), in MDD with attempted suicide than those without (779±231 vs 993±298, p=0.024) at the baseline. The BDNF concentrations remarkably increased in response to SSRI treatment. Significant correlations were noted between the BDNF concentrations and suicide ideation or attempted suicide (p<0.01), but not with HAMD24 or depression. BDNF 196G>A correlated with neither suicide ideation nor treatment responses. CONCLUSION: BDNF concentrations were significantly lower in patients with attempted suicide/ideation. BDNF concentrations could serve as a response marker for antidepressant treatment in MDD.