Treatment-Resistant Depression (TRD)Depressive DisordersAnxiety DisordersObsessive-Compulsive Disorder (OCD)Alcohol Use Disorder (AUD)Tobacco/Nicotine Use Disorder (TUD)Palliative & End-of-Life DistressSet & SettingImmunology & InflammationSubstance Use Disorders (SUD)

Clinical and biological predictors of psychedelic response in the treatment of psychiatric and addictive disorders: a systematic review

This systematic review (2021) of studies from 1990 to 2020 aimed to determine factors that can predict successful response to psychedelic treatment. In a variety of disorders, the authors found that the intensity of the experience was the best such predictor.

Authors

  • Romeo, B.
  • Hermand, M.
  • Pétillion, A.

Published

Journal of Psychiatric Research
meta Study

Abstract

Background

The use of psychedelic treatments has shown very promising results in some psychiatric and addictive disorders, but not all patients achieved a response.

Aim

The aim of this review is to explore the clinical and biological factors which could predict the response to psychedelics in psychiatric and addictive disorders.

Methods

A systematic research was performed on MEDLINE, PsycInfo, Web of science, and Scopus databases from January 1990 to May 2020. All studies investigating the predictive factors of response to psychedelics regardless of psychiatric or addictive disorders, were included.

Results

Twenty studies investigating addictive disorder, treatment-resistant depression, obsessive-compulsive disorder and depressive and anxiety symptoms in patients with life-threatening cancer were included in this review. We found that, in all indications, the main predictive factor of response to psychedelics is the intensity of the acute psychedelic experience. Indeed, we found this factor for alcohol and tobacco use disorders, treatment-resistant depression, and anxiety and depressive symptoms in patients with life-threatening cancer, but not for obsessive-compulsive disorder.

Conclusion

The intensity of the acute psychedelic experience was the main predicting factor of response. The action mechanism of this experience was not clear, but some hypotheses could be made, such as a modulation of serotoninergic system by 5-HT2A receptors agonism, a modulation of the default mode network (DMN) with an acute modular disintegration of the DMN followed by a re-integration of this network with a normal functioning, or an anti-inflammatory effect of this treatment.

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Research Summary of 'Clinical and biological predictors of psychedelic response in the treatment of psychiatric and addictive disorders: a systematic review'

Introduction

Psychedelic treatments have re-emerged in psychiatric research over the past two decades after earlier work in the mid-20th century. Recent clinical studies report promising efficacy signals across several indications: a 57% response rate at day 7 after a single ayahuasca administration in treatment‑resistant depression (TRD), reductions in heavy drinking days in alcohol use disorder (AUD), sustained abstinence in some tobacco-smoking cohorts (67% abstinence at 12 months after psilocybin in one report), and improvements in anxiety and depressive symptoms in patients with life‑threatening cancer. The biological mechanisms proposed to underlie these effects include agonism at serotonin receptors (notably 5‑HT2A), downstream glutamatergic activation and neurotrophic effects, transient modulation of the default mode network (DMN) with subsequent reintegration, and possible anti‑inflammatory actions. Clinical efficacy is also thought to depend heavily on ‘‘set and setting’’ and on psychotherapeutic support provided before, during and after dosing sessions. Romeo and colleagues set out to identify clinical and biological predictors of response to psychedelic interventions in psychiatric and addictive disorders. The investigators conducted a systematic review to determine which baseline characteristics, aspects of the acute psychedelic experience, imaging markers or other measures were associated with subsequent clinical outcomes, with the stated aim of better defining which patients are most likely to benefit from these treatments.

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Study Details

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