Therefore, correlations between BDNF levels and BPRS sub-scores were estimated, yielding the following results (Table 3): Rating scales of hostility (p = 0.0006), suspiciousness (p = 0.0260), conceptual disorganization (p = 0.0409), tension (p = 0.0228), uncooperativeness (p = 0.0006), excitement (p < 0.0001), and mannerisms and posturing (p = 0.0139) were positively correlated with BDNF levels in MDD+BD patients after ECT. Here, BDNF is linked to major depressive disorder.