05-qEEG predictors of response to antidepressive treatment with ketamine

Abstract

Objective Time-course of ketamine effect was assessed in depressive patients by QEEG to elucidate changes associated with treatment and to assess potential predictors of response. Methods The analysis was completed from data of two double-blind, cross-over, placebo-controlled studies, assessing the effect of ketamine infusion (0.54 mg/kg) in 51 inpatients with MDD. EEG data were analysed during the infusion (10 and 30 min) and 24hours after ketamine administration using eLORETA. Results Ketamine induced immediate decrease of parietooccipital alpha-sources and an increase of gamma-sources in all subjects. Better response to treatment was connected with higher pre-treatment alpha activity in parietooccipital region, lower theta sources in mediofrontal areas and rostral cingulate and with lower lagged-phase alpha synchronization. Responders were also characterized by increase of mediofrontal delta/theta sources immediately after ketamine infusion. The intensity of psychotomimetic symptoms were strong predictor of ketamine antidepressive effect. Conclusion Our results suggest that higher pre-treatment occipital alpha activity together with lower theta activity in anterior cingulate and mediofrontal cortex and lower alpha lagged phase synchronization could serve as moderators of treatment response to ketamine. The antidepressive effect of ketamine seems to be undoubtedly connected with patient‘s psychotomimetic experience. Supported by grant AZV MZCR 15-33250A.