Background:
Alteration of brain derived neurotrophic factor (BDNF) has been suggested as a mechanism of ketamine’s anti-depressant effects. Although ketamine use during electroconvulsive therapy (ECT) has gained support, studies have been equivocal regarding its efficacy. The aim of this prospective dual-arm randomized clinical trial is to evaluate ketamine’s anti-depressive effects and plasma BDNF changes when used as a primary anesthetic for ECT.
Methods:
Subjects undergoing ECT index course were randomized and blinded to receive either methohexital (1.0mg/kg) or ketamine (1.0mg/kg) anesthesia. Demographics, periprocedural hemodynamics, seizure data, depression severity using self-reported and clinician-assessed questionnaires were gathered before and after ECT. Cognitive scoring and plasma BDNF concentrations were also obtained before and after ECTs.
Results:
There were no differences in demographics, hemodynamics, seizure lengths or cognitive scores between the ketamine (n=11;72 ECTs) and methohexital (n=11;59 ECTs) groups. Ketamine caused more significant improvement in depression after final ECT (clinician-assessed questinnaire ; p=0.02) and 72 hours later (self-reported questionnaire; p=0.01) compared with methohexital. Higher pre-ECT plasma BDNF were correlated with better pre-ECT PHQ-9 scores (p=0.01). Though pre-ECT plasma BDNF serum levels were similar in both groups (p=0.71), BDNF increased after ECT only in the ketamine arm (p=0.01).
Conclusions:
Our data suggest that ketamine may be beneficial as an anesthetic for ECT and that plasma BDNF correlates with the severity of depression supporting the neurotrophic hypothesis of depression. Further studies are warranted to evaluate sustainability of ketamine’s anti-depressant effects in ECT and role of BDNF as a marker of depression.
