No changes in plasma brain-derived neurotrophic factor levels in treatment-resistant depression patients who...

To examine changes in plasma brain-derived neurotrophic factor (BDNF) levels in patients undergoing electroconvulsive therapy or magnetic seizure therapy, as well as any early or late variations in BDNF. Specific changes related to each technique were also evaluated.

We measured plasma BDNF before and throughout treatment in adult patients (18 to 65 years old) diagnosed with treatment-resistant depression who underwent convulsive therapy (electroconvulsive therapy or magnetic seizure therapy) in the ElectroMagnetic Convulsive therapy for DEpression (EMCODE) project.

We enrolled 31 participants (mean age = 38.4 years, SD = 11.88), of whom 14 (45.16%) underwent electroconvulsive therapy and 17 (54.84%) underwent magnetic seizure therapy. Notable improvements in depressive symptoms were observed in both groups, with no significant differences between them (p = 0.1046). However, no significant changes in plasma BDNF levels were observed for either technique pre- or post-treatment (mean difference = -93.01 pg/mL, 95%CI 545.88-359.86) or over time (coefficient = -67.95, standard error = 37.75, p = 0.072).

The findings suggest that no significant changes occurred in plasma BDNF levels following convulsive therapy, which challenges the notion that BDNF is a biomarker for treatment-resistant depression.