Trial PaperBipolar DisorderDepressive DisordersSchizophreniaAdolescentsMajor Depressive Disorder (MDD)SuicidalityImmunology & InflammationKetamine

Comparative effectiveness of repeated ketamine infusions in treating anhedonia in bipolar and unipolar depression

This open-label study (n=97) investigated the effects of six intravenous ketamine infusions (35mg/70kg) on anhedonia (the inability to feel pleasure) in patients with major depressive disorder (MDD) (n=77) or bipolar depression (BD) (n=20). A significant reduction in the MADRS anhedonia subscale score was observed at 4hrs after the first infusion and was maintained with repeated infusions. Reductions were similar in both MDD and BD groups.

Authors

  • Yuping Ning
  • Wei Zheng

Published

Journal of Affective Disorders
individual Study

Abstract

Objectives

Anhedonia is a common, persistent, and disabling phenomenon in patients with major depressive disorder (MDD) and bipolar depression (BD). This study was conducted to investigate the comparative effectiveness of repeated ketamine infusions in treating anhedonia in Chinese individuals suffering from MDD and BD.

Methods

Ninety-seven individuals suffering from MDD (n = 77) or BD (n = 20) were treated with six intravenous infusions of ketamine (0.5 mg/kg) administered over 40 min. Anhedonia was measured through the Montgomery-Åsberg Depression Rating Scale (MADRS). The antianhedonic response and remission were defined as ≥ 50% and ≥ 75% reduction in MADRS anhedonia subscale score one day after the sixth infusion, respectively.

Results

Anti-anhedonic response and remission rates after the sixth ketamine infusion were 48.5% (95% confidence interval = 38.3%-58.6%) and 30.9% (95% confidence interval = 21.6%-40.3%), respectively. When compared to baseline, a significant reduction in the MADRS anhedonia subscale score was observed at 4 h after the first infusion and was maintained with repeated infusions at any time point (all Ps < 0.05). The anti-anhedonic effect of ketamine did not differ between the MDD and BD groups.

Conclusion

This preliminary study found that repeated ketamine infusions appeared to be effective at rapidly ameliorating anhedonia, with similar efficacy in MDD and BD.

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Research Summary of 'Comparative effectiveness of repeated ketamine infusions in treating anhedonia in bipolar and unipolar depression'

Introduction

Anhedonia, defined as a reduced capacity to experience or anticipate pleasure, is a core symptom of both major depressive disorder (MDD) and bipolar depression (BD). The extracted text notes that clinically significant anhedonia affects a substantial minority of patients (up to 37% in MDD and 52% in BD) and is associated with poorer treatment outcomes. Conventional antidepressant treatments have limited efficacy for anhedonia and can produce emotional blunting or sexual side effects. Non‑pharmacological approaches such as electroconvulsive therapy and transcranial magnetic stimulation have shown some benefit, but no approved medication specifically targets anhedonia. Zheng and colleagues frame ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, as a promising rapid‑acting treatment that has previously reduced depressive symptoms and suicidal ideation in MDD and BD and shown antianhedonic effects after single infusions. Biological mechanisms discussed by the authors include brain-derived neurotrophic factor (BDNF), inflammatory and kynurenine pathways, and reversal of anhedonic phenotypes in animal models. The primary aim of this single-arm, open-label study was to evaluate the antianhedonic effects of six intravenous ketamine infusions (0.5 mg/kg) in a sample of Chinese patients with MDD and BD, and to compare outcomes between the diagnostic groups.

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Study Details

References (6)

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Cited By (2)

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4 cited
Antianhedonic effects of serial intravenous subanaesthetic ketamine in anxious versus nonanxious depression

Zheng, W., Yang, X. H., Gu, L. M. et al. · Journal of Affective Disorders (2022)

10 cited

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