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Cited by 134Posttraumatic Stress Disorder ResearchNeuroendocrine regulation and behaviorStress Responses and Cortisol

Intranasal Oxytocin to Prevent Posttraumatic Stress Disorder Symptoms: A Randomized Controlled Trial in Emergency Department Patients

Open access
van Zuiden, Mirjam, Frijling, Jessie L., Nawijn, Laura, Koch, Saskia B.J., Goslings, J. Carel, Luitse, Jan S., Biesheuvel, Tessa H., Honig, Adriaan +2 more·2017·Biological Psychiatry
DOI 10.1016/j.biopsych.2016.11.012
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Abstract

Background There are currently few preventive interventions available for posttraumatic stress disorder (PTSD). Intranasal oxytocin administration early after trauma may prevent PTSD, because oxytocin administration was previously found to beneficially impact PTSD vulnerability factors, including neural fear responsiveness, peripheral stress reactivity, and socioemotional functioning. Therefore, we investigated the effects of intranasal oxytocin administration early after trauma on subsequent clinician-rated PTSD symptoms. We then assessed whether baseline characteristics moderated the intervention's effects.Methods We performed a multicenter, randomized, double-blind, placebo-controlled clinical trial. Adult emergency department patients with moderate to severe acute distress (n = 120; 85% accident victims) were randomized to intranasal oxytocin (8 days/40 IU twice daily) or placebo (8 days/10 puffs twice daily), initiated within 12 days posttrauma. The Clinician-Administered PTSD Scale (CAPS) was administered at baseline (within 10 days posttrauma) and at 1.5, 3, and 6 months posttrauma. The intention-to-treat sample included 107 participants (oxytocin: n = 53; placebo: n = 54).Results We did not observe a significant group difference in CAPS total score at 1.5 months posttrauma (primary outcome) or across follow-up (secondary outcome). Secondary analyses showed that participants with high baseline CAPS scores receiving oxytocin had significantly lower CAPS scores across follow-up than participants with high baseline CAPS scores receiving placebo.Conclusions Oxytocin administration early after trauma did not attenuate clinician-rated PTSD symptoms in all trauma-exposed participants with acute distress. However, participants with high acute clinician-rated PTSD symptom severity did show beneficial effects of oxytocin. Although replication is warranted, these findings suggest that oxytocin administration is a promising preventive intervention for PTSD for individuals with high acute PTSD symptoms.

AI snapshot

Written from the paper’s full text.

TL;DR

In a multicenter randomized placebo-controlled trial, repeated intranasal oxytocin initiated early after trauma did not reduce clinician-rated PTSD symptoms overall in emergency department patients with acute distress. However, secondary moderator analyses found that oxytocin-treated participants with high acute PTSD symptom severity (baseline CAPS ≥45) had significantly lower PTSD symptoms across 6-month follow-up than placebo-treated participants.

Key findings

  • No significant group difference in the primary outcome, CAPS total score at 1.5 months posttrauma: oxytocin n=43, mean 25.84 (SD 22.97) vs placebo n=48, mean 27.44 (SD 22.03); square-root transformed mean difference 0.23 (SE 0.45), t89=0.509, p=.612, Cohen’s d=0.107.
  • Across follow-up, CAPS scores decreased significantly over time (B=-0.35, SE=0.05, t=-7.175, p<.001), but there was no significant overall intervention effect on intercept (B=-0.30, SE=0.37, t=-0.826, p=.409) or linear slope (B=0.04, SE=0.07, t=0.504, p=.614; Cohen’s d=0.133).
  • Baseline CAPS total score significantly moderated the intervention effect on follow-up CAPS scores (baseline CAPS × intervention on intercept: B=-0.73, SE=0.30, t=-2.389, p=.017). For participants with baseline CAPS ≥45, oxytocin was associated with lower CAPS scores across follow-up than placebo (F1,106=8.212, p=.006, Cohen’s d=0.864); for baseline CAPS <45, no significant effect was found (F1,106=0.822, p=.367, Cohen’s d=-0.221).
  • In exploratory pairwise comparisons among participants with baseline CAPS ≥45, oxytocin-treated participants also had lower IES-R (F1,107=8.181, p=.005, Cohen’s d=0.869), HADS-depression (F1,107=7.180, p=.014, Cohen’s d=0.752), and HADS-anxiety (F1,106=4.982, p=.038, Cohen’s d=0.623) scores across follow-up. Overall self-reported PTSD, anxiety, and depression symptoms did not show significant group differences (Cohen’s d: IES-R 0.195; HADS-anxiety 0.207; HADS-depression 0.113).

Methods

  • Multicenter, double-blind, randomized placebo-controlled trial in three Amsterdam emergency departments; adults aged 18–65 with moderate to severe acute distress after trauma were screened, and 120 were randomized. The intention-to-treat sample included 107 participants (oxytocin n=53; placebo n=54); 85% were accident victims.
  • Participants received intranasal oxytocin (40 IU/dose, twice daily for 8 days) or placebo (0.9% NaCl, 10 puffs twice daily), initiated within 12 days posttrauma. The Clinician-Administered PTSD Scale (CAPS) was administered at baseline within 10 days posttrauma and at 1.5, 3, and 6 months; primary outcome was CAPS total score at 1.5 months.
  • Analyses were intention-to-treat in SPSS v22, with multiple imputation for missing outcome data and linear mixed models for follow-up CAPS, IES-R, and HADS scores. Moderator analyses examined sex, childhood trauma, peritraumatic/immediate distress, and baseline acute symptom severity; a preplanned interim analysis after 50% of planned inclusion found conditional power <.20 and recruitment was halted.

Limitations

  • The paper states that inclusion was halted after the interim analysis showed low conditional power, resulting in a modest sample size; replication is important.
  • The paper states considerable variability in baseline CAPS scores: only 40.2% scored above the CAPS ≥45 threshold; screeners may have had lower specificity for PTSD than previously reported, and PTSD screening positives declined from 19.8% at 1.5 months to 6.0% at 6 months. It also notes that 23% reported mental health care use during follow-up, which may have stimulated help-seeking and contributed to symptom decrease.
  • The paper states that >80% of participants visited the ED because of accidents, so trauma type moderation could not be investigated; it also did not investigate different timing, dosage, or duration of oxytocin administration. Evident from the text: the beneficial findings in high acute PTSD symptom participants come from secondary and exploratory analyses and require replication.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.biopsych.2016.11.012

Cites

73 of 73 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 35 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    HADS-depression scores at follow-up significantly decreased over time.

    “IES-R, HADS-anxiety, and HADS-depression scores at follow-up also significantly decreased over time”
    Quote in the paperNot a substantial claim
  • Findingown data

    No significant group difference in CAPS total score at 1.5 months posttrauma between oxytocin and placebo (primary outcome).

    “There was no significant difference in CAPS total score at 1.5 months posttrauma between oxytocin (n 5 43, mean [SD]: 25.84 [22.97]) and placebo (n 5 48, mean [SD]: 27.44 [22.03]; square root transformed mean difference [SE]: 0.23 [0.45], t 89 5 0.509, p 5 .612,95% confidence interval: -0.67 to 1.13, Cohen's d 5 0.107).”
    Quote in the paperSubstantial claim
  • Findingown data

    CAPS total scores significantly decreased from 1.5 to 6 months posttrauma.

    “CAPS total scores significantly decreased from 1.5 to 6 months posttrauma (B [SE]: -0.35 [0.05], t 5 -7.175, p , .001)”
    Quote in the paperNot a substantial claim
  • Findingown data

    IES-R scores at follow-up significantly decreased over time.

    “IES-R, HADS-anxiety, and HADS-depression scores at follow-up also significantly decreased over time”
    Quote in the paperNot a substantial claim
  • Findingown data

    HADS-anxiety scores at follow-up significantly decreased over time.

    “IES-R, HADS-anxiety, and HADS-depression scores at follow-up also significantly decreased over time”
    Quote in the paperNot a substantial claim
  • May combine two claims. 14
  • Classified as probably not a substantial claim. 8
  • The quote only partly states this claim. 1

  • May combine two claims.

    Findingown data

    No significant group differences in overall symptom severity or symptom decrease over time for IES-R, HADS-anxiety, and HADS-depression.

    “without significant group differences in overall symptom severity or symptom decrease over time (Cohen's d 5 IES-R, 0.195; HADS-anxiety, 0.207; HADS-depression, 0.113; Table 2).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In both treatment groups, PTSD symptom severity decreased steadily over time, with the percentage of participants screening positive for PTSD declining from 19.8% at 1.5 months posttrauma to 6.0% at 6 months posttrauma.

    “in both treatment groups we observed a steady decrease in PTSD symptom severity over time: the percentage of participants screening positive for PTSD declined from 19.8% at 1.5 months posttrauma to 6.0% at 6 months posttrauma.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data

    No significant group differences in demographic, trauma and screening, or baseline clinical characteristics.

    “We observed no significant group differences in demographic, trauma and screening, or baseline clinical characteristics.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    In recently trauma-exposed individuals, intranasal oxytocin within 10 days posttrauma increased amygdala reactivity to fearful faces and decreased amygdala-ventrolateral prefrontal functional connectivity after a trauma reminder.

    “In recently traumaexposed individuals, however, intranasal oxytocin within 10 days posttrauma increased amygdala reactivity to fearful faces (27) and decreased amygdala-ventrolateral prefrontal functional connectivity after a trauma reminder (28).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [27] Frijling, 2016, Effects of intranasal oxytocin on amygdala reactivity to emotional faces in recently trauma-exposed individuals, Soc Cogn Affect Neurosci source

      Not checked in the free run.

    • cites [28] Frijling, 2016, Intranasal oxytocin affects amygdala functional connectivity after trauma script-driven imagery in distressed recently trauma-exposed individuals, Neuropsychopharmacology source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    Participants receiving oxytocin reported having administered significantly more intranasal doses than those receiving placebo.

    “participants receiving oxytocin reported having administered significantly more intranasal doses than those receiving placebo (Mann-Whitney U: 742.00, p 5 .017).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data

    No significant group differences in subjective intervention allocation awareness, use of mental health care or psychopharmaceuticals, or reported adverse events during the trial.

    “In addition, there were no significant group differences in subjective intervention allocation awareness, use of mental health care or psychopharmaceuticals (Table 1), or reported adverse events during the trial (Supplemental Table S2).”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Study design and conductown data

    Analyses in completers only showed comparable results to intention-to-treat analyses.

    “Analyses in completers only (oxytocin: n 5 39, placebo: n 5 40) showed comparable results (Table 2).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Oxytocin administration may modulate glucocorticoid and autonomic stress reactivity, dampen anxiety and neural threat processing, and beneficially impact socioemotional processes and prosocial behavior.

    “Accumulating evidence from studies in animals and in healthy and psychiatric human populations shows that oxytocin administration may modulate glucocorticoid (16) and autonomic stress reactivity (17), dampen anxiety and neural threat processing (18,19), and beneficially impact socioemotional processes and prosocial behavior (20,21) [but see also (22,23) for seemingly nonprosocial effects].”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [16] Cardoso, 2014, A meta-analytic review of the impact of intranasal oxytocin administration on cortisol concentrations during laboratory tasks: Moderation by method and mental health, Psychoneuroendocrinology source

      Not checked in the free run.

    • cites [17] Kubzansky, 2012, A heartfelt response: Oxytocin effects on response to social stress in men and women, Biol Psychol source

      Not checked in the free run.

    • cites [18] Kirsch, 2005, Oxytocin modulates neural circuitry for social cognition and fear in humans, J Neurosci source

      Not checked in the free run.

    • cites [19] Wigton, 2015, Neurophysiological effects of acute oxytocin administration: Systematic review and meta-analysis of placebo-controlled imaging studies, J Psychiatry Neurosci source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The need for effective and safe PTSD prevention is longstanding and ongoing, with no preventive interventions currently at the stage of widespread implementation.

    “Notably, the need for effective and safe PTSD prevention is longstanding and ongoing, with no preventive interventions currently at the stage of widespread implementation (57).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [57] Howlett, 2016, Prevention of trauma and stressor-related disorders: A review, Neuropsychopharmacology source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data

    The interim analysis at 50% of planned inclusion indicated low conditional power to detect a significant effect of oxytocin on clinician-rated PTSD symptom severity at study completion, and inclusion was halted.

    “As the interim analysis at 50% of planned inclusion indicated low conditional power to detect a significant effect of oxytocin on clinician-rated PTSD symptom severity at study completion, we halted inclusion.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    An online cognitive behavioral therapy-based intervention only reduced PTSD symptoms in participants with high acute PTSD symptoms.

    “an online cognitive behavioral therapy-based intervention only reduced PTSD symptoms in participants with high acute PTSD symptoms (63).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [63] Mouthaan, 2013, Internet-based early intervention to prevent posttraumatic stress disorder in injury patients: Randomized controlled trial, J Med Internet Res source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The oxytocin intervention was initiated within approximately 2 weeks posttrauma, and therefore it is also of interest for use in ED patients for whom immediate intervention is not feasible or in traumatized populations that are not immediately brought to the attention of health care professionals.

    “In addition, the oxytocin intervention was initiated within approximately 2 weeks posttrauma, and therefore it is also of interest for use in ED patients for whom immediate intervention is not feasible or in traumatized populations that are not immediately brought to the attention of health care professionals.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The study may have included more participants with relatively low PTSD risk than anticipated, potentially explaining why a differential intervention effect dependent on clinician-rated acute PTSD severity was found instead of the hypothesized overall intervention effect.

    “Therefore, we may have included more participants with relatively low PTSD risk than anticipated, potentially also explaining why we found a differential intervention effect dependent on clinician-rated acute PTSD severity instead of the hypothesized overall intervention effect.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    The lower specificity of the screeners may be because the screening questionnaires were administered earlier after trauma than in previous validation studies.

    “This may be because our screening questionnaires were administered earlier after trauma than in previous validation studies.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    Oxytocin-treated participants with high acute PTSD symptoms had significantly lower PTSD symptom severity across the complete follow-up period up to 6 months posttrauma, indicating a long-term protective effect.

    “Relative to placebo-treated individuals with high acute PTSD symptoms, oxytocin-treated participants with high acute PTSD symptoms had significantly lower PTSD symptom severity across the complete follow-up period up to 6 months posttrauma, indicating a long-term protective effect.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Previously, hydrocortisone and prolonged exposure initiated within 12 hours posttrauma in ED patients, and brief cognitive behavioral therapy within the first weeks posttrauma in patients with acute stress disorder, were found to reduce subsequent PTSD symptom severity.

    “Previously, hydrocortisone (4,5) and prolonged exposure (3) initiated within 12 hours posttrauma in ED patients, and brief cognitive behavioral therapy within the first weeks posttrauma in patients with acute stress disorder (6), were found to reduce subsequent PTSD symptom severity.”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [4] Delahanty, 2013, The efficacy of initial hydrocortisone administration at preventing posttraumatic distress in adult trauma patients: A randomized trial, CNS Spectr source

      Not checked in the free run.

    • cites [5] Zohar, 2011, High dose hydrocortisone immediately after trauma may alter the trajectory of PTSD: Interplay between clinical and animal studies, Eur Neuropsychopharmacol source

      Not checked in the free run.

    • cites [3] Rothbaum, 2012, Early intervention may prevent the development of posttraumatic stress disorder: A randomized pilot civilian study with modified prolonged exposure, Biol Psychiatry source

      Not checked in the free run.

    • cites [6] Roberts, 2010, Early psychological interventions to treat acute traumatic stress symptoms, Cochrane Database Syst Rev

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The study did not investigate whether a different timing, dosage, or duration of oxytocin administration would also be effective in reducing subsequent PTSD symptom severity.

    “we did not investigate whether a different timing, dosage, or duration of oxytocin administration would also be effective in reducing subsequent PTSD symptom severity.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In rodents, central oxytocin administration before conditioned fear extinction improved social fear extinction but impaired nonsocial fear extinction.

    “in rodents, central oxytocin administration before conditioned fear extinction improved social fear extinction (68) but impaired nonsocial fear extinction (69).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [68] Zoicas, 2014, Brain oxytocin in social fear conditioning and its extinction: Involvement of the lateral septum, Neuropsychopharmacology source

      Not checked in the free run.

    • cites [69] Toth, 2012, Central administration of oxytocin receptor ligands affects cued fear extinction in rats and mice in a timepoint-dependent manner, Psychopharmacology (Berl) source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    Rothbaum et al. observed that rape victims benefitted most from early prolonged exposure compared to ED patients with other types of trauma exposure.

    “Rothbaum et al. (3) observed that rape victims benefitted most from early prolonged exposure compared to ED patients with other types of trauma exposure.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [3] Rothbaum, 2012, Early intervention may prevent the development of posttraumatic stress disorder: A randomized pilot civilian study with modified prolonged exposure, Biol Psychiatry source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    There is ongoing debate on the pharmacodynamics of intranasal oxytocin administration.

    “There is ongoing debate on pharmacodynamics of intranasal oxytocin administration (70)(71)(72)(73).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [70] Carson, 2016, Improving research standards to restore trust in intranasal oxytocin, Biol Psychiatry source

      Not checked in the free run.

    • cites [71] Leng, 2016, Intranasal oxytocin: Myths and delusions, Biol Psychiatry source

      Not checked in the free run.

    • cites [72] Quintana, 2016, Intranasal oxytocin mechanisms can be better understood, but its effects on social cognition and behavior are not to be sniffed at, Biol Psychiatry source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    Participating in the trial may have stimulated participants to seek professional help relatively early, which could be an alternative explanation for the observed steady decrease in symptom severity.

    “This may indicate that participating in this trial stimulated participants to seek professional help relatively early, which could be an alternative explanation for the observed steady decrease in symptom severity.”
    Quote in the paperNot a substantial claim
21 of 21

  • The paper relies on this without support.

    It had not yet been investigated whether oxytocin administration early after trauma may prevent PTSD development.

    “It has not yet been investigated whether oxytocin administration early after trauma may prevent PTSD development.”

  • The paper relies on this without support.

    Actual clinical effects of oxytocin administration in recently trauma-exposed individuals were not investigated.

    “However, actual clinical effects were not investigated.”

  • The paper relies on this without support.

    This study is the largest published clinical randomized controlled trial on effects of intranasal oxytocin on psychiatric symptoms to date.

    “This study is the largest published clinical randomized controlled trial on effects of intranasal oxytocin on psychiatric symptoms to date.”

  • The paper relies on this without support.

    This is the first randomized controlled trial assessing whether sex, trauma history, and baseline symptom severity moderate the effects of repeated oxytocin administration.

    “to the best of our knowledge, this is the first randomized controlled trial assessing whether sex, trauma history, and baseline symptom severity moderate the effects of repeated oxytocin administration.”
4 of 4

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

  • Sex moderator slope confidence interval is inconsistent with its estimate

    Minor

    The slope confidence interval has a midpoint of 0.47, far from the reported estimate of -0.07; its upper bound appears inconsistent with the estimate and standard error.

    Reported -0.07 · recomputed 0.47

  • Placebo dropout percentage uses the wrong denominator

    Minor

    The table gives 54 placebo participants. Six dropouts among 54 participants is 11.1% to one decimal place, not 11.3%.

    Reported 11.3 · recomputed 11.111111

2 of 2

Cites

Flagged first, then by citations

1 of the 74 references couldn’t be matched to a known paper.

Research works printed but not linked: 1

  1. deRoon-Cassini, 2014, Prediction of chronic PTSD using early fMRI evidence of emotion dysregulation in trauma survivors, Biol Psychiatry, 75, 169S

Cited by

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Related

Authors
van Zuiden, M., Frijling, J. L., Nawijn, L., Koch, S. B. J., Goslings, J. C., Luitse, J. S., Biesheuvel, T. H., Honig, A., Veltman, D. J., & Olff, M.
Affiliations
  • Amsterdam UMC Location University of Amsterdam (NL)
  • Amsterdam UMC Location Vrije Universiteit Amsterdam (NL)
  • OLVG (NL)
  • Arq Psychotrauma Expert Group (NL)
ORCID
Venue
Biological Psychiatry
Publisher
Elsevier BV
Published
2017-06
Volume
81
Issue
12
Pages
1030-1040
ISSN
0006-3223 (ISSN-L)
DOI
10.1016/j.biopsych.2016.11.012
OpenAlex
W2560374635
Semantic Scholar
bd1046552426fd73c914244a4959edc03a4d85fe
Cited by
134
References
74
Citations by year
2026: 8 · 2025: 6 · 2024: 7 · 2023: 9 · 2022: 18 · 2021: 19 · 2020: 13 · 2019: 20 · 2018: 26 · 2017: 8
FWCI
23.90
Type
journal article
Language
en
Open access
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Biological Psychiatry (publishedVersion)
  • PubMed (publishedVersion)
  • Amsterdam UMC (VU Amsterdam) - Institutional Repository (publishedVersion)
  • Data Archiving and Networked Services (DANS) (submittedVersion)
  • Pure Amsterdam UMC (submittedVersion)
Funders
ZonMw (91210041)
Topics
  • Social Sciences › Psychology › Clinical Psychology › Posttraumatic Stress Disorder Research
  • Social Sciences › Psychology › Social Psychology › Neuroendocrine regulation and behavior
  • Life Sciences › Neuroscience › Behavioral Neuroscience › Stress Responses and Cortisol
Keywords
intranasal oxytocin, emergency department patients, placebo-controlled intervention, accident victims, intervention moderators
MeSH terms
Administration, Intranasal, Adolescent, Adult, Aged, Double-Blind Method, Emergency Service, Hospital, Female, Humans, Male, Middle Aged, Oxytocin, Stress Disorders, Post-Traumatic, Treatment Outcome, Young Adult

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