Trial PaperAnxiety DisordersDepressive DisordersTreatment-Resistant Depression (TRD)Neurocognitive DisordersHealthy VolunteersKetamine

Neurocognitive Effects of Ketamine and Association with Antidepressant Response in Individuals with Treatment-Resistant Depression: A Randomized Controlled Trial

This randomised, double-blind, active placebo-controlled study (n=62) investigated the neurocognitive and antidepressant effects of ketamine (35 mg/70kg) or midazolam (3.15mg/70kg) compared to the benzodiazepine anesthetic midazolam in patients with depression. Neurocognitive performance improved independently of treatment condition or change in depression severity due to learning, which indicates an absence of adverse effects of ketamine on neurocognitive functioning in contrast to electroconvulsive therapy which impacts memory.

Authors

  • Sanjay Mathew
  • James Murrough
  • Dennis Charney

Published

Neuropsychopharmacology
individual Study

Abstract

Introduction

The glutamate N-methyl-D-aspartate (NMDA) receptor antagonist ketamine displays rapid antidepressant effects in patients with treatment-resistant depression (TRD); however, the potential for adverse neurocognitive effects in this population has not received adequate study. The current study was designed to investigate the delayed neurocognitive impact of ketamine in TRD and examine baseline antidepressant response predictors in the context of a randomized controlled trial.

Methods

In the current study, 62 patients (mean age=46.2±12.2) with TRD free of concomitant antidepressant medication underwent neurocognitive assessments using components of the MATRICS Consensus Cognitive Battery (MCCB) before and after a single intravenous infusion of ketamine (0.5 mg/kg) or midazolam (0.045 mg/kg). Participants were randomized to ketamine or midazolam in a 2:1 fashion under double-blind conditions and underwent depression symptom assessments at 24, 48, 72 h, and 7 days post treatment using the Montgomery-Asberg Depression Rating Scale (MADRS). Post-treatment neurocognitive assessment was conducted once at 7 days.

Results

Neurocognitive performance improved following the treatment regardless of treatment condition. There was no differential effect of treatment on neurocognitive performance and no association with antidepressant response. Slower processing speed at baseline uniquely predicted greater improvement in depression at 24 h following ketamine (t=2.3, p=0.027), while controlling for age, depression severity, and performance on other neurocognitive domains.

Discussion

In the current study, we found that ketamine was devoid of adverse neurocognitive effects at 7 days post treatment and that slower baseline processing speed was associated with greater antidepressant response. Future studies are required to further define the neurocognitive profile of ketamine in clinical samples and to identify clinically useful response moderators.

Available with Blossom Pro

Research Summary of 'Neurocognitive Effects of Ketamine and Association with Antidepressant Response in Individuals with Treatment-Resistant Depression: A Randomized Controlled Trial'

Introduction

Ketamine is a high-affinity, noncompetitive NMDA glutamate receptor antagonist that has demonstrated rapid antidepressant effects in patients with treatment-resistant depression (TRD). Although single-dose ketamine (commonly 0.5 mg/kg over a slow 40-minute infusion) produces acute dissociative and cognitive effects that typically resolve within hours, there is limited data on its delayed or persistent neurocognitive impact in clinical mood-disorder populations. Prior work by the same group and others reported acute memory impairments following ketamine in healthy volunteers and in an open-label TRD sample, and an earlier observation that slower baseline processing speed was associated with greater antidepressant response at 24 hours. Murrough and colleagues designed the present two-site, double-blind, randomised controlled trial to extend those findings. The study aimed to (1) characterise the effect of a single sub-anesthetic ketamine infusion on neurocognitive performance measured 7 days post-treatment, and (2) examine whether baseline neurocognitive functioning predicts rapid antidepressant response to ketamine. The primary hypothesis was that ketamine would not worsen neurocognitive functioning at 7 days and that slower baseline processing speed would predict greater symptom improvement at 24 hours.

Expert Research Summaries

Go Pro to access AI-powered section-by-section summaries, editorial takes, and the full research toolkit.

Full Text PDF

Full Paper PDF

Create a free account to open full-text PDFs.

Study Details

References (3)

Papers cited by this study that are also in Blossom

Antidepressant Efficacy of Ketamine in Treatment-Resistant Major Depression: A Two-Site Randomized Controlled Trial

Murrough, J. W., Iosifescu, D. V., Chang, L. C. et al. · American Journal of Psychiatry (2013)

Rapid and Longer-Term Antidepressant Effects of Repeated Ketamine Infusions in Treatment-Resistant Major Depression

Murrough, J. W., Perez, A. M., Pillemer, S. et al. · Biological Psychiatry (2012)

Replication of Ketamine’s Antidepressant Efficacy in Bipolar Depression: A Randomized Controlled Add-On Trial

Zarate, C. A., Brutsche, N. E., Ibrahim, L. et al. · Biological Psychiatry (2012)

757 cited

Cited By (21)

Papers in Blossom that reference this study

Neurocognitive effects of subanesthetic serial ketamine infusions in treatment resistant depression

Zavaliangos-Petropulu, A., Mcclintock, S. M., Khalil, J. et al. · Journal of Affective Disorders (2023)

Ketamine as Add-On Treatment in Psychotic Treatment-Resistant Depression

Chmielewska, Z., Jakuszkowiak-Wojten, K., Wiglusz, M. S. et al. · Brain Sciences (2023)

Acute effects of ketamine and esketamine on cognition in healthy subjects: A meta-analysis

Zhornitsky, S., Pelletier, R., Assaf, R. et al. · Progress in Neuro-Psychopharmacology and Biological Psychiatry (2022)

Neurocognitive effects of repeated ketamine infusions in comorbid posttraumatic stress disorder and major depressive disorder

Albott, C. S., Lim, K. O., Erbes, C. et al. · Journal of Affective Disorders (2022)

Acute cognitive effects of single-dose intravenous ketamine in major depressive and posttraumatic stress disorder

Davis, M. T., Dellagiogia, N., Maruff, P. et al. · Translational Psychiatry (2021)

Show all 21 papers
Targeting glutamate signalling in depression: progress and prospects

Murrough, J. W., Abdallah, C. G., Mathew, S. J. · Nature Reviews Drug Discovery (2021)

Antidepressant and neurocognitive effects of serial ketamine administration versus ECT in depressed patients

Basso, L., Bönke, L., Aust, S. et al. · Journal of Psychiatric Research (2020)

159 cited
Altered peripheral immune profiles in treatment-resistant depression: response to ketamine and prediction of treatment outcome

Kiraly, D. D., Horn, S. R., Van Dam, N. T. et al. · Translational Psychiatry (2017)

Ketamine for the treatment of major depressive disorder and bipolar depression: A review of the literature

Grady, S. E., Marsh, T. A., Tenhouse, A. et al. · Mental Health Clinician (2017)

Ketamine for treatment-resistant depression: recent developments and clinical applications

Schwartz, J., Murrough, J. W., Iosifescu, D. V. · Evidence-Based Mental Health (2016)

Ketamine for Treatment-Resistant Unipolar and Bipolar Major Depression: Critical Review and Implications for Clinical Practice

Bobo, W. V., Vande Voort, J. L., Croarkin, P. E. et al. · Depression and Anxiety (2016)

Ketamine as a promising prototype for a new generation of rapid-acting antidepressants

Abdallah, C. G., Averill, L. A., Krystal, J. H. · Annals of the New York Academy of Sciences (2015)

Your Personal Research Library

Go Pro to save papers, add notes, rate studies, and organize your research into custom shelves.