Distinct association of plasma BDNF concentration and cognitive function in depressed patients treated with vortioxetine or escitalopram.

Cognitive dysfunction is frequent in major depressive disorder (MDD), and brain-derived neurotrophic factor (BDNF) is involved both in regulation of cognition and in therapeutic response in MDD. The aim of this study was to determine if baseline plasma BDNF might predict change in cognitive function in MDD patients treated with vortioxetine or escitalopram, and whether the alterations in BDNF levels correlate with changes in cognitive performance during treatment. Drug-naive or drug-free patients with MDD (N=121) were sampled and evaluated at baseline and 4 weeks after treatment initiation with vortioxetine or escitalopram. Cognitive function was evaluated using the F-A-S test, Digit Span test, and Digit Symbol Coding test. Plasma BDNF was determined using ELISA. The results of the study indicate that both vortioxetine (V) and escitalopram (E) improved cognitive functions evaluated with F-A-S test (V: p<0.001; r=−0.427, E: p<0.001; r=−0.370), Digit Symbol Coding test (V: p<0.001; r=−0.706, E: p<0.001; r=−0.435), and Digit Span test-backward span (V: p=0.001; r=−0.311, E: p=0.042; r=−0.185), while only vortioxetine (p<0.001; r=−0.325) improved cognition evaluated with the Digit Span test-forward span. A moderate positive correlation between pretreatment plasma BDNF levels and improvement in cognitive performance was only detected in patients treated with vortioxetine (delta F-A-S test: p=0.011; r=0.325, delta Digit Span test-forward span: p=0.010, r=0.326). These results suggest that higher baseline plasma BDNF levels might be associated with improvements in verbal fluency and working memory in vortioxetine, but not escitalopram treated patients. Vortioxetine treatment was superior in simple attention efficiency.