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Roger S McIntyre

University of Toronto, University Health Network

138 papers in the library · 4,098 citations · publishing 0-2026

Papers

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Active mechanisms of ketamine-assisted psychotherapy: A systematic review.

Journal of Affective Disorders October 15, 2022 Isak Joneborg, Yena Lee, Joshua D. Di Vincenzo et al.

Few studies have evaluated the efficacy of ketamine-assisted psychotherapy (KAP) in the treatment of treatment-resistant depression (TRD) and substance use disorders (SUD). A systematic review of clinical trials reporting on the efficacy of KAP and discussing mechanisms of action, identified on PubMed and PsycInfo. Five randomized-controlled trials reported on the efficacy of KAP treatment and...

A Research Domain Criteria (RDoC)-Guided Dashboard to Review Psilocybin Target Domains: A Systematic Review.

CNS Drugs October 1, 2022 Niloufar Pouyan, Zahra Halvaei Khankahdani, Farnaz Younesi Sisi et al. 16 citations

Preliminary results from randomized controlled studies as well as identified molecular, cellular, and circuit targets of select psychedelics (e.g., psilocybin) suggest that their effects are transdiagnostic. In this review, we exploit the Research Domain Criteria (RDoC) transdiagnostic framework, to synthesize extant literature on psilocybin. We aimed to identify RDoC-based effects of...

DOI: 10.1007/s40263-022-00944-y (opens in new tab) Full text (opens in new tab) Psychedelics Mental health research Behavioral neuroscience Psilocybin therapy +1

The Canadian Network for Mood and Anxiety Treatments (CANMAT) Task Force Report: Serotonergic Psychedelic Treatments for Major Depressive Disorder

The Canadian Journal of Psychiatry August 17, 2022 Joshua D. Rosenblat, Muhammad Ishrat Husain, Yena Lee et al. 58 citations

Objective Serotonergic psychedelics are re-emerging as potential novel treatments for several psychiatric disorders including major depressive disorder. The Canadian Network for Mood and Anxiety Treatments (CANMAT) convened a task force to review the evidence and provide a consensus recommendation for the clinical use of psychedelic treatments for major depressive disorder. Methods A systematic...

A review of potential neuropathological changes associated with ketamine

Expert Opinion on Drug Safety May 3, 2022 Danica Nogo, Hana Nazal, Yuetong Song et al. 17 citations

INTRODUCTION: Ketamine is an established intervention for treatment-resistant depression (TRD). However, long-term adverse effects with repeated doses remain insufficiently characterized. Although several animal models have shown N-methyl-D-aspartate glutamate receptor antagonists to produce various neuropathological reactions, attention surrounding the risk of brain lesions has been minimal....

Real-world effectiveness of ketamine in treatment-resistant depression: A systematic review & meta-analysis.

Journal of Psychiatric Research May 1, 2022 Yazen Alnefeesi, David C J Chen-Li, Ella Krane et al. 177 citations

Ketamine is a promising therapeutic option in treatment-resistant depression (TRD). The acute efficacy of ketamine in TRD has been demonstrated in replicated randomised-controlled trials (RCTs), but the generalizability of RCT data to real-world practice is limited. To this end, we conducted a systematic review (Search date: 25/12/2021; 1482 records identified) and meta-analysis of studies...

The abuse liability of ketamine: A scoping review of preclinical and clinical studies.

Journal of Psychiatric Research May 1, 2022 Tuyen T. Le, Isabel Pazos Cordero, Muhammad Youshay Jawad et al. 82 citations

While ketamine has been used clinically over the past decades, it has only been recently shown to be a promising therapy for treatment-resistant depression (TRD). However, ketamine and related dissociative agents may also be misused recreationally, creating significant concerns for abuse liability when prescribed for depression. Although the abuse potential of ketamine is widely recognized,...

The Effects of Psilocybin in Adults with Major Depressive Disorder and the General Population: Findings from Neuroimaging Studies

Psychiatry Research April 25, 2022 Hartej Gill, Parnian Puramat, Pankti Patel et al. 16 citations

The use of psilocybin as treatment for major depressive disorder (MDD) has been examined as a promising alternative to traditional first-line options. We reviewed existing literature to provide a synthesis of the extant neuroimaging observations with psilocybin, and to identify putative therapeutic targets for target engagement studies with psilocybin, and potentially other psychedelics. We...

Hallucinogen persisting perceptual disorder: a scoping review covering frequency, risk factors, prevention, and treatment

Expert Opinion on Drug Safety April 15, 2022 Marcus A. Doyle, Susan Ling, Leanna M.W. Lui et al. 24 citations

INTRODUCTION: Hallucinogen persisting perception disorder (HPPD) affects a subset of persons who use hallucinogens and is defined as the repeated experience of hallucinations and other perceptual disturbances as a result of prior intoxications. As select hallucinogens are under development for the treatment of selectmental disorders, there is a need to better characterize this disorder. AREAS...

The efficacy and safety of adjunctive intranasal esketamine treatment in major depressive disorder: a systematic review and meta-analysis

Expert Opinion on Drug Safety April 6, 2022 Muhammad Youshay Jawad, Joshua D. Di Vincenzo, Felicia Ceban et al. 29 citations

INTRODUCTION: Intranasal (IN) esketamine represents an innovative treatment for individuals with treatment resistant depression and depression with suicidal ideation and behavior. Herein, we synthesize extant long-term studies (≥ 4 weeks) regarding this treatment. RESEARCH DESIGN AND METHODS: The interventional studies of IN esketamine in patients with depression having a study period of at...

Intravenous ketamine for depression: A clinical discussion reconsidering best practices in acute hypertension management.

Frontiers in Psychiatry 2022 Ryan Yip, Jennifer Swainson, Atul Khullar et al. 13 citations

Ketamine is a versatile medication with an emerging role for the treatment of numerous psychiatric conditions, including treatment resistant depression. Current psychiatry guidelines for its intravenous administration to treat depression recommend regular blood pressure monitoring and an aggressive approach to potential transient hypertensive episodes induced by ketamine infusions. While this...

DOI: 10.3389/fpsyt.2022.1017504 (opens in new tab) Full text (opens in new tab) Hypertension Hypertensive emergency Ketamine infusion Treatment resistant depression

Frequency analysis of symptomatic worsening following ketamine infusions for treatment resistant depression in a real-world sample: Results from the canadian rapid treatment center of excellence.

Psychiatry Research 2022 Joshua D. Di Vincenzo, Orly Lipsitz, Nelson B Rodrigues et al. 11 citations

Antidepressants are associated with symptomatic worsening in a subgroup of patients. Replicated evidence has demonstrated rapid and robust antidepressant effects with intravenous (IV) ketamine in treatment resistant depression (TRD); however, the risk of ketamine worsening depressive symptoms in a subgroup of patients remains unknown. Herein we report a retrospective analysis on the rates of...

Molecular Mechanisms of Psilocybin and Implications for the Treatment of Depression

CNS Drugs November 17, 2021 Susan Ling, Felicia Ceban, Leanna M.W. Lui et al. 123 citations

Therapeutic deficiencies with monoaminergic antidepressants invites the need to identify and develop novel rapid-acting antidepressants. Hitherto, ketamine and esketamine are identified as safe, well-tolerated rapid-acting antidepressants in adults with treatment-resistant depression, and also mitigate measures of suicidality. Psilocybin is a naturally occurring psychoactive alkaloid and...

Ketamine for psychotic depression: An overview of the glutamatergic system and ketamine's mechanisms associated with antidepressant and psychotomimetic effects.

Psychiatry Research October 1, 2021 Tuyen T. Le, Joshua D. Di Vincenzo, Kayla M Teopiz et al. 26 citations

Approximately 0.35-1% of the general population is afflicted with psychotic depression at some time in their life. Psychotic depression is a subtype of major depressive disorder characterized by mood congruent hallucinations and/or delusions. Patients with psychotic depression often represent the most severe cases, with high relapse and mortality rate. Although treatment guidelines recommend a...

Registered clinical studies investigating psychedelic drugs for psychiatric disorders.

Journal of Psychiatric Research July 1, 2021 Ashley N. Siegel, Shakila Meshkat, Katie Benitah et al. 101 citations

Psychedelics are a hallucinogenic class of psychoactive drugs with the primary effect of activating non-ordinary states of consciousness. Due to the positive preliminary findings of these drugs in the treatment of psychiatric disorders, the number of registered clinical studies has risen significantly. In this paper, clinical studies registered on clinicaltrials.gov that evaluate the treatment...

Do sleep changes mediate the anti‐depressive and anti‐suicidal response of intravenous ketamine in treatment‐resistant depression?

Journal of Sleep Research June 16, 2021 Nelson B Rodrigues, Roger S McIntyre, Orly Lipsitz et al. 28 citations

Summary Sleep disturbances are commonly reported in patients with treatment‐resistant depression (TRD). Available data have shown that intravenous (IV) ketamine is an effective treatment for patients with TRD and growing data suggest ketamine may improve overall sleep architecture. In the present study, we evaluated whether changes in sleep symptoms mediated the anti‐depressive and/or...

Strategies to Prolong Ketamine’s Efficacy in Adults with Treatment-Resistant Depression

Advances in Therapy April 30, 2021 Eric P. Mcmullen, Yena Lee, Orly Lipsitz et al.

Ketamine treatment is capable of significant and rapid symptom improvement in adults with treatment-resistant depression (TRD). A limitation of ketamine treatment in TRD is the relatively short duration of time to relapse (e.g., median 2–4 weeks). The objective of the systematic review herein is to identify strategies capable of prolonging the acute efficacy of ketamine in adults with TRD....

Synthesizing the Evidence for Ketamine and Esketamine in Treatment-Resistant Depression: An International Expert Opinion on the Available Evidence and Implementation

American Journal of Psychiatry March 17, 2021 Roger S McIntyre, Joshua D. Rosenblat, Charles B. Nemeroff et al. 694 citations

Replicated international studies have underscored the human and societal costs associated with major depressive disorder. Despite the proven efficacy of monoamine-based antidepressants in major depression, the majority of treated individuals fail to achieve full syndromal and functional recovery with the index and subsequent pharmacological treatments. Ketamine and esketamine represent...

The effectiveness, safety and tolerability of ketamine for depression in adolescents and older adults: A systematic review.

Journal of Psychiatric Research March 1, 2021 Joshua D. Di Vincenzo, Ashley N. Siegel, Orly Lipsitz et al. 59 citations

The majority of antidepressant medication trials have focused on adult populations (ages 18-65), with much less research in older and younger populations. Moreover, key differences in the efficacy and safety of antidepressants have been identified between these age groups. Ketamine has emerged as a promising new treatment for treatment resistant depression (TRD). The objective of this review is...

Validation of the McIntyre And Rosenblat Rapid Response Scale (MARRRS) in Adults with Treatment-Resistant Depression Receiving Intravenous Ketamine Treatment.

Journal of Affective Disorders March 1, 2021 Roger S McIntyre, Nelson B Rodrigues, Orly Lipsitz et al. 10 citations

BACKGROUND Depression severity and efficacy measurement scales employed for rapid-acting treatments (e.g., ketamine) were initially validated in adults receiving conventional monoamine-based antidepressants. The emergence of rapid-acting antidepressants in psychiatry provides the impetus for outcome measures that have been validated as sensitive to change with rapid-acting treatments. Herein,...

Efficacy of dextromethorphan for the treatment of depression: a systematic review of preclinical and clinical trials

Expert Opinion on Emerging Drugs January 2, 2021 Amna Majeed, Jiaqi Xiong, Kayla M Teopiz et al. 48 citations

INTRODUCTION: The large percentage of adults with major depressive disorder (MDD) insufficiently responding and/or tolerating conventional monoamine-based antidepressants invites the need for mechanistically novel treatments. Convergent evidence implicates glutamatergic signaling as a potential therapeutic target in MDD. AREAS COVERED: The synthesis herein of preclinical and clinical studies...

A simplified 6-Item clinician administered dissociative symptom scale (CADSS-6) for monitoring dissociative effects of sub-anesthetic ketamine infusions.

Journal of Affective Disorders December 29, 2020 Nelson B Rodrigues, Roger S McIntyre, Orly Lipsitz et al.

BACKGROUND Dissociation is a treatment-emergent adverse event commonly associated with IV ketamine, often measured using the 23-item Clinician-Administered Dissociative States Scale (CADSS). The objective of this study was to develop a short form version of the CADSS for easier clinical use. METHODS Retrospective data of 260 patients with treatment-resistant depression (TRD) receiving IV...

The acute antisuicidal effects of single-dose intravenous ketamine and intranasal esketamine in individuals with major depression and bipolar disorders: A systematic review and meta-analysis.

Journal of Psychiatric Research December 11, 2020 Jiaqi Xiong, Orly Lipsitz, David C J Chen-Li et al. 122 citations

The efficacy of ketamine in reducing suicidal ideation (SI) has been previously reported. We aimed to evaluate acute anti-SI effects of single-dose ketamine in different formulations/routes of administration by pooling results from randomized controlled trials (RCTs). A systematic search was conducted on Cochrane, Embase, Medline, and PubMed from inception to July 1st, 2020. Studies were...

Effectiveness of intravenous ketamine in mood disorder patients with a history of neurostimulation

CNS Spectrums December 10, 2020 Nelson B Rodrigues, Ashley N. Siegel, Orly Lipsitz et al. 17 citations

BACKGROUND: Patients unsuccessfully treated by neurostimulation may represent a highly intractable subgroup of depression. While the efficacy of intravenous (IV) ketamine has been established in patients with treatment-resistant depression (TRD), there is an interest to evaluate its effectiveness in a subpopulation with a history of neurostimulation. METHODS: This retrospective, posthoc...

Does body mass index predict response to intravenous ketamine treatment in adults with major depressive and bipolar disorder? Results from the Canadian Rapid Treatment Center of Excellence

CNS Spectrums December 3, 2020 Orly Lipsitz, Roger S McIntyre, Nelson B Rodrigues et al. 25 citations

BACKGROUND: Higher body mass index (BMI) has been found to predict greater antidepressant response to intravenous (IV) ketamine treatment. We evaluated the association between BMI and response to repeat-dose IV ketamine in patients with treatment-resistant depression (TRD). METHODS: Adults (N = 230) with TRD received four infusions of IV ketamine at a community-based clinic. Changes in symptoms...

The Effects of Ketamine on Cognition in Treatment-Resistant Depression: A Systematic Review and Priority Avenues for Future Research.

Neuroscience & Biobehavioral Reviews November 23, 2020 Hartej Gill, Barjot Gill, Nelson B Rodrigues et al. 92 citations

Replicated evidence has documented cognitive deficits in populations with treatment-resistant depression (TRD). Approximately 40% of patients with MDD present with impairment of one or more cognitive domains. As such, there is an unmet need to discover treatments that have pro-cognitive effects in TRD patients. Ketamine has demonstrated efficacy as a rapid-onset intervention for the treatment...