ArticleThe international journal of neuropsychopharmacology2022
A Participant-Level Integrative Data Analysis of Differential Placebo Response for Suicidal Ideation and Nonsuicidal Depressive Symptoms in Clinical Trials of Intravenous Racemic Ketamine.
Article in The international journal of neuropsychopharmacology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers, 1 of them a synthesis that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
5 citing papers in PubMed, 1 synthesis or guideline pooled it, 8 citations in OpenAlex.
- Neurophysiological biomarkers of treatment response in suicidal ideation: a systematic review.Translational psychiatry · 2025Pooled it
- A pilot randomized controlled trial of ketamine in Borderline Personality Disorder.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2023Trial
- Psychedelic therapeutics in psychiatric conditions.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2026Review
- Clinical indicators of the suicide crisis and response to ketamine.Journal of affective disorders · 2025Article
- Ketamine in neuropsychiatric disorders: an update.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2024Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
11 authors at 7 institutions in 2 countries.
Funding
Abstract
backgroundClinical trials of intravenous (IV) racemic (R,S)-ketamine (hereafter referred to as IV ketamine) have consistently reported rapid and substantial reductions in overall depressive symptoms compared with saline (inactive placebo) or midazolam (active placebo). The evidence for IV ketamine's specific effects on suicidal ideation is less clear, however. This study sought to examine whether differential placebo (saline or midazolam) response to overall depressive symptoms vs suicidal ideation may help explain these divergent findings.
methodsData for this participant-level integrative data analysis were drawn from 151 participants across 10 studies, and linear regression was used to examine the relationship between placebo response for suicidal ideation vs other depressive symptoms indexed from standard rating scales-specifically, depressed mood, anhedonia, anxiety, and guilt-over time.
resultsFor participants receiving saline placebo (n = 46), greater placebo response was observed for suicidal ideation compared with other symptoms indexed from standard depression rating scales, except for anxiety. For those receiving midazolam placebo (n = 105), greater placebo response was observed for suicidal ideation compared with depressed mood or anhedonia, and no significant differences were observed when comparing suicidal ideation with anxiety or guilt.
conclusionsTaken together, the results provide preliminary evidence of a differential placebo response for suicidal ideation vs other depressive symptoms, while anxiety and suicidal ideation appear to produce similar placebo response profiles. These findings may help explain the more modest findings in clinical IV ketamine trials for suicidal ideation than overall depression.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.