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Psychiatry

Therapeutic effects of classic serotonergic psychedelics: A systematic review of modern-era clinical studies

Abstract

Objective: To conduct a systematic review of modern-era (post-millennium) clinical studies assessing the therapeutic effects of serotonergic psychedelics drugs for mental health conditions. Although the main focus was on efficacy and safety, study characteristics, duration of antidepressants effects across studies, and the role of the subjective drug experiences were also reviewed and presented.

Method: A systematic literature search (1 Jan 2000 to 1 May 2020) was conducted in PubMed and PsychINFO for studies of patients undergoing treatment with a serotonergic psychedelic.

Results: Data from 16 papers, representing 10 independent psychedelic-assisted therapy trials (psilocybin = 7, ayahuasca = 2, LSD = 1), were extracted, presented in figures and tables, and narratively synthesized and discussed. Across these studies, a total of 188 patients suffering either cancer- or illness-related anxiety and depression disorders (C/I-RADD), major depressive disorder (MDD), obsessive-compulsive disorder (OCD) or substance use disorder (SUD) were included. The reviewed studies established feasibility and evidence of safety, alongside promising early data of efficacy in the treatment of depression, anxiety, OCD, and tobacco and alcohol use disorders. For a majority of patients, the therapeutic effects appeared to be long-lasting (weeks-months) after only 1 to 3 treatment session(s). All studies were conducted in line with guidelines for the safe conduct of psychedelic therapy, and no severe adverse events were reported.

Conclusion: The resurrection of clinical psychedelic research provides early evidence for treatment efficacy and safety for a range of psychiatric conditions, and constitutes an exciting new treatment avenue in a health area with major unmet needs.

Andersen, K., Carhart-Harris, R., Nutt, D. J., & Erritzoe, D. (2021). Therapeutic effects of classic serotonergic psychedelics: A systematic review of modern-era clinical studies. Acta psychiatrica Scandinavica, 143(2), 101–118. https://doi.org/10.1111/acps.13249

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Hallucinations Under Psychedelics and in the Schizophrenia Spectrum: An Interdisciplinary and Multiscale Comparison

Abstract

The recent renaissance of psychedelic science has reignited interest in the similarity of drug-induced experiences to those more commonly observed in psychiatric contexts such as the schizophrenia-spectrum. This report from a multidisciplinary working group of the International Consortium on Hallucinations Research (ICHR) addresses this issue, putting special emphasis on hallucinatory experiences. We review evidence collected at different scales of understanding, from pharmacology to brain-imaging, phenomenology and anthropology, highlighting similarities and differences between hallucinations under psychedelics and in the schizophrenia-spectrum disorders. Finally, we attempt to integrate these findings using computational approaches and conclude with recommendations for future research.

Leptourgos, P., Fortier-Davy, M., Carhart-Harris, R., Corlett, P. R., Dupuis, D., Halberstadt, A. L., Kometer, M., Kozakova, E., LarØi, F., Noorani, T. N., Preller, K. H., Waters, F., Zaytseva, Y., & Jardri, R. (2020). Hallucinations Under Psychedelics and in the Schizophrenia Spectrum: An Interdisciplinary and Multiscale Comparison. Schizophrenia bulletin, 46(6), 1396–1408. https://doi.org/10.1093/schbul/sbaa117

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Effect of Ketamine on Rumination in Treatment-Resistant Depressive Patients

Abstract

Background: A rapid antidepressant effect of ketamine has repeatedly been documented in the literature, and identifying clinical features associated with a better response to this treatment is currently an essential question. Considering the relationship between rumination and depression and the need to identify potential predictors of response to ketamine, we analyzed the effect of a single injection of ketamine 0.5 mg/kg on rumination in treatment-resistant depressive (TRD) patients and explored whether baseline ruminative style and early improvements of rumination would predict a greater antidepressant effect of ketamine.

Methods: Ten TRD outpatients who participated in a 4-week open study on the antidepressant effect of ketamine also completed the Ruminative Response Scale the day before, the day after, and a week after ketamine administration.

Results: We found that in our patients, a single rapid 1-minute intravenous injection of ketamine 0.5 mg/kg was efficacious in reducing rumination, but neither severity of rumination at baseline nor early improvements of rumination after ketamine injection predicted antidepressant response.

Conclusions: Our preliminary data suggest that a single injection of ketamine 0.5 mg/kg can be efficacious in reducing rumination in TRD patients but rumination does not seem to be a useful clinical predictor of response to ketamine. Larger studies are necessary to confirm these results.

Vidal, S., Jermann, F., Aubry, J. M., Richard-Lepouriel, H., & Kosel, M. (2020). Effect of Ketamine on Rumination in Treatment-Resistant Depressive Patients. Journal of clinical psychopharmacology, 40(6), 607–610. https://doi.org/10.1097/JCP.0000000000001305

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Neurocognitive impact of ketamine treatment in major depressive disorder: A review on human and animal studies – PubMed

Abstract

Background: Most recent evidence support a rapid and sustained antidepressant effect of subanesthetic dose of intravenous ketamine in patients with major depressive disorder (MDD). However, clinical and animal studies investigating the effects of intravenous ketamine on specific functional domains disrupted by depression reported conflicting results. Therefore, the aim of this review is to provide an overview of the recent findings exploring the cognitive effects of ketamine in depression.
Methods: After a bibliographic search on PubMed, Medline and PsycInfo, we retrieved 11 original studies meeting our research criteria, 7 in humans with MDD or Treatment Resistant Disorder and 4 using rats models for depression.
Results: Overall the results showed that a) ketamine reduced activation and normalized connectivity measures of several brain regions related to depressive behaviors and reversed deficits in cognitive flexibility and coping response strategy in rats with depressive features, and b) ketamine leads to a no significant impairment on neurocognitive functions in most of the studies, with only three studies observing improvements in speed of processing, verbal learning, sustained attention and response control, verbal and working memory.
Limitations: The methodological heterogeneity, in terms of neuropsychological tests used and cognitive domain explored, of the studies included.
Conclusions: Most of the studies included showed no significant cognitive impairments in MDD patients after ketamine treatment. Furthermore, the results of the fMRI studies considered suggest that ketamine may have a normalizing effect on brain functions during attentional and emotional processing in MDD patients. However, further studies are needed to confirm these preliminary evidences.
Crisanti, C., Enrico, P., Fiorentini, A., Delvecchio, G., & Brambilla, P. (2020). Neurocognitive impact of ketamine treatment in major depressive disorder: A review on human and animal studies. Journal of Affective Disorders., 10.1016/j.jad.2020.07.119
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Metabolic Risk Factors and Cardiovascular Safety in Ketamine Use for Treatment Resistant Depression

Abstract

Introduction: Ketamine exhibits antidepressant properties in treatment-resistant depression (TRD) with some concern over its cardiovascular safety and tolerability issues. This paper reports on the cardiovascular safety in short-term intravenous ketamine treatment in TRD inpatients with major depressive disorder (MDD) and bipolar disorder (BP).

Materials and methods: The observational study population comprises 35 MDD and 14 BP subjects treated with intravenous ketamine.

Results: Blood pressure (RR) and heart rate (HR) values returned to baseline within 1.5-hours post infusion with no sequelae for all study subjects. Six time points were analyzed for each infusion: 0′, 15′, 30′, 45′, 60′ and 90′ for RR and HR. After the infusion significant peaks in systolic (p = 0.004) and diastolic (p = 0.038) RR were seen. In concomitant medication with selective serotonin reuptake inhibitors (SSRIs), higher RR peaks (p = 0.020; p = 0.048) were seen as compared to other subjects. The decrease in HR was greater (p = 0.02) in the absence of concomitant medication with mood stabilizers as compared to subjects receiving mood stabilizing medication accompanied by the observation of a greater decrease in diastolic RR among those taking mood stabilizers (p = 0.009).

Limitations: The study may be underpowered due to the small sample size. The observations apply to an inhomogeneous TRD population in a single-site, pilot study, with no blinding and are limited to the acute administration.

Conclusion: The study demonstrates good safety and tolerability profile of intravenous ketamine as add-on intervention to current psychotropic medication in TRD, regardless of the MDD or BP type of mood disorders. The abatement of elevated RR and BP scores was observed in time with no sequelae nor harm. Still, cardiovascular risks appear to be more pronounced in subjects with comorbid arterial hypertension and diabetes mellitus.

Szarmach, J., Cubała, W. J., Włodarczyk, A., & Gałuszko-Węgielnik, M. (2020). Metabolic Risk Factors and Cardiovascular Safety in Ketamine Use for Treatment Resistant Depression. Neuropsychiatric disease and treatment, 16, 2539–2551. https://doi.org/10.2147/NDT.S273287

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Rapid and sustained decreases in suicidality following a single dose of ayahuasca among individuals with recurrent major depressive disorder: results from an open-label trial

Abstract

Rationale: Suicidality is a major public health concern with limited treatment options. Accordingly, there is a need for innovative interventions for suicidality. Preliminary evidence indicates that treatment with the psychedelic ayahuasca may lead to decreases in depressive symptoms among individuals with major depressive disorder (MDD). However, there remains limited understanding of whether ayahuasca also leads to reductions in suicidality.

Objective: To examine the acute and post-acute effect of ayahuasca on suicidality among individuals with MDD.

Methods: We conducted a secondary analysis of an open-label trial in which individuals with recurrent MDD received a single dose of ayahuasca (N = 17). Suicidality was assessed at baseline; during the intervention; and 1, 7, 14, and 21 days after the intervention.

Results: Among individuals with suicidality at baseline (n = 15), there were significant acute (i.e., 40, 80, 140, and 180 min after administration) and post-acute (1, 7, 14, and 21 days after administration) decreases in suicidality following administration of ayahuasca. Post-acute effect sizes for decreases in suicidality were large (Hedges’ g = 1.31-1.75), with the largest effect size 21 days after the intervention (g = 1.75).

Conclusions: When administered in the appropriate context, ayahuasca may lead to rapid and sustained reductions in suicidality among individuals with MDD. Randomized, double-blind studies with larger sample sizes are needed to confirm this early finding.

Zeifman, R. J., Singhal, N., Dos Santos, R. G., Sanches, R. F., de Lima Osório, F., Hallak, J., & Weissman, C. R. (2021). Rapid and sustained decreases in suicidality following a single dose of ayahuasca among individuals with recurrent major depressive disorder: results from an open-label trial. Psychopharmacology, 238(2), 453–459. https://doi.org/10.1007/s00213-020-05692-9

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Predicting therapeutic response to oral ketamine for chronic suicidal ideation: a Bayesian network for clinical decision support

Abstract

Background: The glutamatergic modulator ketamine has been shown to result in rapid reductions in both suicidal ideation (SI) and depressive symptoms in clinical trials. There is a practical need for identification of pre-treatment predictors of ketamine response. Previous studies indicate links between treatment response and body mass index (BMI), depression symptoms and previous suicide attempts. Our aim was to explore the use of clinical and demographic factors to predict response to serial doses of oral ketamine for chronic suicidal ideation.

Methods: Thirty-two participants completed the Oral Ketamine Trial on Suicidality (OKTOS). Data for the current study were drawn from pre-treatment and follow-up time-points of OKTOS. Only clinical and sociodemographic variables were included in this analysis. Data were used to create a proof of concept Bayesian network (BN) model of variables predicting prolonged response to oral ketamine, as defined by the Beck Scale for Suicide Ideation (BSS).

Results: The network of potential predictors of response was evaluated using receiver operating characteristic (ROC) curve analyses. A combination of nine demographic and clinical variables predicted prolonged ketamine response, with strong contributions from BMI, Social and Occupational Functioning Assessment Scale (SOFAS), Montgomery-Asberg Depression Rating Scale (MADRS), number of suicide attempts, employment status and age. We evaluated and optimised the proposed network to increase the area under the ROC curve (AUC). The performance evaluation demonstrated that the BN predicted prolonged ketamine response with 97% accuracy, and AUC = 0.87.

Conclusions: At present, validated tools to facilitate risk assessment are infrequently used in psychiatric practice. Pre-treatment assessment of individuals’ likelihood of response to oral ketamine for chronic suicidal ideation could be beneficial in making more informed decisions about likelihood of success for this treatment course. Clinical trials registration number ACTRN12618001412224, retrospectively registered 23/8/2018.

Beaudequin, D., Can, A. T., Dutton, M., Jones, M., Gallay, C., Schwenn, P., Yang, C., Forsyth, G., Simcock, G., Hermens, D. F., & Lagopoulos, J. (2020). Predicting therapeutic response to oral ketamine for chronic suicidal ideation: a Bayesian network for clinical decision support. BMC psychiatry, 20(1), 519. https://doi.org/10.1186/s12888-020-02925-1

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Toxicokinetics and Toxicodynamics of Ayahuasca Alkaloids N, N-Dimethyltryptamine (DMT), Harmine, Harmaline and Tetrahydroharmine: Clinical and Forensic Impact

Abstract

Ayahuasca is a hallucinogenic botanical beverage originally used by indigenous Amazonian tribes in religious ceremonies and therapeutic practices. While ethnobotanical surveys still indicate its spiritual and medicinal uses, consumption of ayahuasca has been progressively related with a recreational purpose, particularly in Western societies. The ayahuasca aqueous concoction is typically prepared from the leaves of the N,N-dimethyltryptamine (DMT)-containing Psychotria viridis, and the stem and bark of Banisteriopsis caapi, the plant source of harmala alkaloids. Herein, the toxicokinetics and toxicodynamics of the psychoactive DMT and harmala alkaloids harmine, harmaline and tetrahydroharmine, are comprehensively covered, particularly emphasizing the psychological, physiological, and toxic effects deriving from their concomitant intake. Potential therapeutic utility, particularly in mental and psychiatric disorders, and forensic aspects of DMT and ayahuasca are also reviewed and discussed. Following administration of ayahuasca, DMT is rapidly absorbed and distributed. Harmala alkaloids act as potent inhibitors of monoamine oxidase A (MAO-A), preventing extensive first-pass degradation of DMT into 3-indole-acetic acid (3-IAA), and enabling sufficient amounts of DMT to reach the brain. DMT has affinity for a variety of serotonergic and non-serotonergic receptors, though its psychotropic effects are mainly related with the activation of serotonin receptors type 2A (5-HT2A). Mildly to rarely severe psychedelic adverse effects are reported for ayahuasca or its alkaloids individually, but abuse does not lead to dependence or tolerance. For a long time, the evidence has pointed to potential psychotherapeutic benefits in the treatment of depression, anxiety, and substance abuse disorders; and although misuse of ayahuasca has been diverting attention away from such clinical potential, research onto its therapeutic effects has now strongly resurged.

Brito-da-Costa, A. M., Dias-da-Silva, D., Gomes, N., Dinis-Oliveira, R. J., & Madureira-Carvalho, Á. (2020). Toxicokinetics and Toxicodynamics of Ayahuasca Alkaloids N,N-Dimethyltryptamine (DMT), Harmine, Harmaline and Tetrahydroharmine: Clinical and Forensic Impact. Pharmaceuticals (Basel, Switzerland), 13(11), 334. https://doi.org/10.3390/ph13110334

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Psychedelic Psychiatry: Preparing for Novel Treatments Involving Altered States of Consciousness

Abstract

The past decade has seen a renaissance of research interest into the psychotherapeutic potential of psychedelic compounds. In 2019, Oakland and Denver became the first two jurisdictions in the United States to decriminalize the possession of psychedelic-containing organisms. As research and public policy continue to evolve, it becomes increasingly plausible that psychedelics will become viable treatment options for psychiatric conditions. Psychiatrists should be integral to models of psychedelic prescription and patient management. The risk for adverse psychological and medical effects from psychedelic sessions necessitates psychiatric supervision. The literature on psychedelic-assisted psychotherapy may provide wisdom regarding practical aspects of managing patients’ treatment sessions.

Holoyda B. (2020). Psychedelic Psychiatry: Preparing for Novel Treatments Involving Altered States of Consciousness. Psychiatric services (Washington, D.C.), 71(12), 1297–1299. https://doi.org/10.1176/appi.ps.202000213

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The effectiveness of intravenous ketamine in adults with treatment-resistant major depressive disorder and bipolar disorder presenting with prominent anxiety: Results from the Canadian Rapid Treatment Center of Excellence

Abstract

Background: Individuals meeting criteria for treatment-resistant depression (TRD) are differentially affected by high levels of anxiety symptoms.

Aims: There is a need to identify the efficacy of novel rapid-onset treatments in adults with mood disorders and comorbid anxious-distress.

Methods: This study included patients with treatment-resistant major depressive disorder (MDD) or bipolar disorder (BD) who were receiving intravenous (IV) ketamine treatment at a community-based clinic.Anxious-distress was proxied using items from the Quick Inventory of Depressive Symptomatology-Self Report 16-item (QIDS-SR16) and Generalized Anxiety Disorder 7-item (GAD7) scales. The difference in QIDS-SR16 total score, QIDS-SR16 suicidal ideation (SI) item and GAD7 score were analyzed between groups.

Results: A total of 209 adults with MDD (n = 177) and BD (n = 26) were included in this analysis. From this sample, 94 patients (mean = 45 ± 13.9 years) met the criteria for anxious-distress. Individuals meeting the criteria for anxious-distress exhibited a significantly greater reduction in QIDS-SR16 total score following four infusions (p = 0.02) when compared with patients not meeting the anxious-distress criteria. Both anxious-distressed and low-anxiety patients exhibited a significant reduction in SI (p < 0.0001) following four infusions.Finally, there was a significantly greater reduction in anxiety symptoms in the anxious-distress group compared with the non-anxious distress group following three (p = 0.02) and four infusions (p < 0.001).

Conclusion: Patients with TRD and prominent anxiety receiving IV ketamine exhibited a significant reduction in depressive, SI and anxiety symptoms.

McIntyre, R. S., Rodrigues, N. B., Lipsitz, O., Nasri, F., Gill, H., Lui, L. M., Subramaniapillai, M., Kratiuk, K., Teopiz, K., Ho, R., Lee, Y., Mansur, R. B., & Rosenblat, J. D. (2021). The effectiveness of intravenous ketamine in adults with treatment-resistant major depressive disorder and bipolar disorder presenting with prominent anxiety: Results from the Canadian Rapid Treatment Center of Excellence. Journal of psychopharmacology (Oxford, England), 35(2), 128–136. https://doi.org/10.1177/0269881120954048

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