OPEN Foundation

Menu
Search
Close this search box.

Depressive Disorders

Prefrontal Connectivity and Glutamate Transmission: Relevance to Depression Pathophysiology and Ketamine Treatment

April 23, 2017 / Depressive Disorders, Ketamine, Neuroscience, Papers / By / , , , , , ,

Abstract

Background

Prefrontal global brain connectivity with global signal regression (GBCr) was proposed as a robust biomarker of depression and was associated with ketamine’s mechanism of action. Here, we investigated prefrontal GBCr in treatment-resistant depression (TRD) at baseline and following treatment. Then, we conducted a set of pharmacological challenges in healthy subjects to investigate the glutamate neurotransmission correlates of GBCr.

Methods

In the cohort A study, we used functional magnetic resonance imaging to compare GBCr between 22 patients with TRD and 29 healthy control subjects. Then, we examined the effects of ketamine and midazolam on GBCr in patients with TRD 24 hours posttreatment. In the cohort B study, we acquired repeated functional magnetic resonance imaging in 18 healthy subjects to determine the effects of lamotrigine (a glutamate release inhibitor), ketamine, and lamotrigine-by-ketamine interaction.

Results

In the cohort A study, patients with TRD showed significant reduction in dorsomedial and dorsolateral prefrontal GBCr compared with healthy control subjects. In patients with TRD, GBCr in the altered clusters significantly increased 24 hours following ketamine (effect size = 1.0, confidence interval = 0.3 to 1.8) but not following midazolam (effect size = 0.5, confidence interval = −0.6 to 1.3). In the cohort B study, oral lamotrigine reduced GBCr 2 hours postadministration, while ketamine increased medial prefrontal GBCr during infusion. Lamotrigine significantly reduced the ketamine-induced GBCr surge. Exploratory analyses showed elevated ventral prefrontal GBCr in TRD and significant reduction of ventral prefrontal GBCr during ketamine infusion in healthy subjects.

Conclusions

This study provides the first replication of the ability of ketamine to normalize depression-related prefrontal dysconnectivity. It also provides indirect evidence that these effects may be triggered by the capacity of ketamine to enhance glutamate neurotransmission.

Abdallah, C. G., Averill, C. L., Salas, R., Averill, L. A., Baldwin, P. R., Krystal, J. H., … & Mathalon, D. H. (2017). Prefrontal Connectivity & Glutamate Transmission: Relevance to Depression Pathophysiology and Ketamine Treatment. Biological Psychiatry: Cognitive Neuroscience and Neuroimaging. 10.1016/j.bpsc.2017.04.006
Link to full text

New Treatment Strategies of Depression: Based on Mechanisms Related to Neuroplasticity

April 11, 2017 / Depressive Disorders, Ketamine, Neuroscience, Papers, Psychology, Publications / By / , ,

Abstract

Major depressive disorder is a severe and complex mental disorder. Impaired neurotransmission and disrupted signalling pathways may influence neuroplasticity, which is involved in the brain dysfunction in depression. Traditional neurobiological theories of depression, such as monoamine hypothesis, cannot fully explain the whole picture of depressive disorders. In this review, we discussed new treatment directions of depression, including modulation of glutamatergic system and noninvasive brain stimulation. Dysfunction of glutamatergic neurotransmission plays an important role in the pathophysiology of depression. Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has rapid and lasting antidepressive effects in previous studies. In addition to ketamine, other glutamatergic modulators, such as sarcosine, also show potential antidepressant effect in animal models or clinical trials. Noninvasive brain stimulation is another new treatment strategy beyond pharmacotherapy. Growing evidence has demonstrated that superficial brain stimulations, such as transcranial magnetic stimulation, transcranial direct current stimulation, cranial electrotherapy stimulation, and magnetic seizure therapy, can improve depressive symptoms. The antidepressive effect of these brain stimulations may be through modulating neuroplasticity. In conclusion, drugs that modulate neurotransmission via NMDA receptor and noninvasive brain stimulation may provide new directions of treatment for depression. Furthermore, exploring the underlying mechanisms will help in developing novel therapies for depression in the future.
Huang, Y. J., Lane, H. Y., & Lin, C. H. (2017). New Treatment Strategies of Depression: Based on Mechanisms Related to Neuroplasticity. Neural plasticity, 2017. 10.1155/2017/4605971
Link to full text

Use of repeated intravenous ketamine therapy in treatment-resistant bipolar depression with suicidal behaviour: a case report from Spain

April 7, 2017 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , , , ,

Abstract

The rapidly-acting antidepressant properties of ketamine are a trend topic in psychiatry. Despite its robust effects, these are ephemeral and can lead to certain adverse events. For this reason, there is still a general concern around the off-label use of ketamine in clinical practice settings. Nonetheless, for refractory depression, it should be an indication to consider. We report the case of a female patient admitted for several months due to a treatment-resistant depressive bipolar episode with chronic suicidal behaviour. After repeated intravenous ketamine infusions without remarkable side effects, the patient experienced a complete clinical recovery during the 4 weeks following hospital discharge. Unfortunately, depressive symptoms reappeared in the 5th week, and the patient was finally readmitted to hospital as a result of a suicide attempt.
López-Díaz, Á., Fernández-González, J. L., Luján-Jiménez, J. E., Galiano-Rus, S., & Gutiérrez-Rojas, L. (2017). Use of repeated intravenous ketamine therapy in treatment-resistant bipolar depression with suicidal behaviour: a case report from Spain. Therapeutic advances in psychopharmacology, 7(4), 137-140. 10.1177/2045125316675578
Link to full text

Clinical predictors of antidepressant response to ketamine in unipolar treatment-resistant depression

April 1, 2017 / Depressive Disorders, Ketamine, Papers, Psychology / By / , , , , , ,

Abstract

Introduction

The non-competitive N-methyl-d-aspartate glutamate receptor antagonist ketamine has been shown to have rapid antidepressant effects in treatment-resistant depression (TRD). However, only a few studies have investigated which clinical characteristics predict a response to ketamine.

Objectives

To assess sociodemographic variables and clinical markers that predict response to ketamine in unipolar TRD patients.

Methods

Searches of Pubmed, NCBI and Google Scholar were conducted for clinical trials and systematic reviews, through October 2016, using the keywords:
ketamine, N-methyl-d-aspartate receptor antagonist, rapid-acting antidepressant, depression, treatment-resistant depression, clinical predictors.

Results

Findings support the following clinical predictors:
– sociodemographic variables: positive family history of alcohol abuse disorder in first-degree relative (increased antidepressant response and fewer depressive symptoms for up to 4 weeks post-infusions), higher BMI (improvement in depression severity at 230 minutes and one day post-infusion), negative history of suicide attempt (greater improvement at day 7);
– infusion-associated events: greater dissociation during infusion (better antidepressant response at 230 minutes and one week post-infusion); rapid response to first infusion (sustained response to subsequent infusions in one-third responders for up to 83 days);
– symptomatology: anxious depression (fewer depression symptoms at day one up to 25 associated with longer time to relapse); neurocognitive performance (lower attention) predicts change in severity of depressive symptoms over six infusions.

Conclusions

Findings suggest that specific clinical characteristics are predictors of ketamine response in TRD. Future studies confirming reliable predictors will assist clinicians to implement efficacious and individualized treatment for TRD patients.

Del Sant, L. C., Magalhães, E., Lucchese, A. C., Alves, H. P., Sarin, L. M., Del Porto, J. A., & de Lacerda, A. T. (2017). Clinical predictors of antidepressant response to ketamine in unipolar treatment-resistant depression. European Psychiatry, 41, S525-S526. 10.1016/j.eurpsy.2017.01.704
Link to full text

S-(+)-ketamine-induced dissociative symptoms as a traumatic experience in patients with treatment-resistant depression

April 1, 2017 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , , ,

Abstract

Ketamine, an NMDA receptor antagonist, is a rapid-acting antidepressant and anti-suicidal agent.1 However, most clinical trials assessing its antidepressant action involve RS-(±)-ketamine, which is considered a more dissociative drug than S-(+)-ketamine.2 In this report, we describe severe psychotomimetic side effects after S-(+)-ketamine infusion therapy in two patients with treatment-resistant depression (TRD), contrasting with previous evidence that S-(+)-ketamine is less prone to inducing these side effects.
Correia-Melo, F. S., Silva, S. S., Araújo-de-Freitas, L., & Quarantini, L. C. (2017). S-(+)-ketamine-induced dissociative symptoms as a traumatic experience in patients with treatment-resistant depression. Revista Brasileira de Psiquiatria, 39(2), 188-189. 10.1590/1516-4446-2016-2070
Link to full text

Ketamine for Depression, 1: Clinical Summary of Issues Related to Efficacy, Adverse Effects, and Mechanism of Action

April 1, 2017 / Depressive Disorders, Ketamine, Papers, Psychology / By /

Abstract

Ketamine is an anesthetic drug that is also used for off-label indications such as the mediation of analgesia and sedation in various settings. It is additionally recognized as an agent with antidepressant potential. For depression, it is most commonly administered as a slow intravenous infusion in subanesthetic doses (usually 0.5 mg/kg). As an antidepressant, is strikingly different from conventional antidepressant drugs in that it brings about rapid and marked attenuation of depressive symptoms even in patients with refractory depression. The benefits are observed within hours of administration, peak after about a day, and are lost 3-12 days later. Patients who do not benefit after the initial dose may benefit with serial dosing or at higher doses. Benefits can be maintained for weeks to months by the continuation of ketamine sessions at 2- to 4-day intervals. Adverse effects include dissociative and psychotomimetic changes that are almost always mild and transient, if present; transient elevation of heart rate and blood pressure often occur. These changes are usually well tolerated and are very seldom responsible for treatment discontinuation. Whereas ketamine is an N-methyl-d-aspartate receptor antagonist, and whereas much is known about its different biological effects, its actions that mediate the antidepressant response are presently not known for certain. Although big data on ketamine are presently unavailable, the drug holds promise in the treatment of depression, especially refractory depression.
Andrade, C. (2017). Ketamine for Depression, 1: Clinical Summary of Issues Related to Efficacy, Adverse Effects, and Mechanism of Action. The Journal of clinical psychiatry, 78(4), e415. 10.4088/JCP.17f11567
Link to full text

A Consensus Statement on the Use of Ketamine in the Treatment of Mood Disorders

April 1, 2017 / Depressive Disorders, Ketamine, Papers, Psychology / By / , , , , , ,

Abstract

IMPORTANCE:
Several studies now provide evidence of ketamine hydrochloride’s ability to produce rapid and robust antidepressant effects in patients with mood and anxiety disorders that were previously resistant to treatment. Despite the relatively small sample sizes, lack of longer-term data on efficacy, and limited data on safety provided by these studies, they have led to increased use of ketamine as an off-label treatment for mood and other psychiatric disorders.
OBSERVATIONS:
This review and consensus statement provides a general overview of the data on the use of ketamine for the treatment of mood disorders and highlights the limitations of the existing knowledge. While ketamine may be beneficial to some patients with mood disorders, it is important to consider the limitations of the available data and the potential risk associated with the drug when considering the treatment option.
CONCLUSIONS AND RELEVANCE:
The suggestions provided are intended to facilitate clinical decision making and encourage an evidence-based approach to using ketamine in the treatment of psychiatric disorders considering the limited information that is currently available. This article provides information on potentially important issues related to the off-label treatment approach that should be considered to help ensure patient safety.

Sanacora, G., Frye, M. A., McDonald, W., Mathew, S. J., Turner, M. S., Schatzberg, A. F., … & Nemeroff, C. B. (2017). A consensus statement on the use of ketamine in the treatment of mood disorders. Jama psychiatry, 74(4), 399-405. 10.1001/jamapsychiatry.2017.0080
Link to full text

Use of Ketamine in Clinical PracticeA Time for Optimism and Caution

April 1, 2017 / Depressive Disorders, Ketamine, Papers, Psychology / By / ,

Abstract

Increasing evidence, primarily from small studies, supports the idea that the dissociative anesthetic ketamine has rapid antidepressant effects in patients with treatment-refractory major depression.1 The beneficial effects of ketamine are observed within hours of administration and can last approximately 1 week. Given that up to one-third of patients with major depression fail current treatments,2 there is a clear need for novel and more effective treatments. Results to date have led to increasing off-label use of ketamine in clinical practices, with little guidance about clinical administration. In this issue of the JAMA Psychiatry, Sanacora and colleagues3 provide a much-needed consensus statement to help guide clinical use of ketamine.
Zorumski, C. F., & Conway, C. R. (2017). Use of ketamine in clinical practice: a time for optimism and caution. Jama psychiatry, 74(4), 405-406. 10.1001/jamapsychiatry.2017.0078
Link to full text

Classic Hallucinogens and Mystical Experiences: Phenomenology and Neural Correlates

March 26, 2017 / Anxiety Disorders / PTSD, Depressive Disorders, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications, Substance Use Disorder / By / ,

Abstract

This chapter begins with a brief review of descriptions and definitions of mystical-type experiences and the historical connection between classic hallucinogens and mystical experiences. The chapter then explores the empirical literature on experiences with classic hallucinogens in which claims about mystical or religious experiences have been made. A psychometrically validated questionnaire is described for the reliable measurement of mystical-type experiences occasioned by classic hallucinogens. Controlled laboratory studies show that under double-blind conditions that provide significant controls for expectancy bias, psilocybin can occasion complete mystical experiences in the majority of people studied. These effects are dose-dependent, specific to psilocybin compared to placebo or a psychoactive control substance, and have enduring impact on the moods, attitudes, and behaviors of participants as assessed by self-report of participants and ratings by community observers. Other studies suggest that enduring personal meaning in healthy volunteers and therapeutic outcomes in patients, including reduction and cessation of substance abuse behaviors and reduction of anxiety and depression in patients with a life-threatening cancer diagnosis, are related to the occurrence of mystical experiences during drug sessions. The final sections of the chapter draw parallels in human neuroscience research between the neural bases of experiences with classic hallucinogens and the neural bases of meditative practices for which claims of mystical-type experience are sometimes made. From these parallels, a functional neural model of mystical experience is proposed, based on changes in the default mode network of the brain that have been observed after the administration of classic hallucinogens and during meditation practices for which mystical-type claims have been made.
Barrett, F. S., & Griffiths, R. R. (2017). Classic Hallucinogens and Mystical Experiences: Phenomenology and Neural Correlates. 10.1007/7854_2017_474
Link to full text

Altered peripheral immune profiles in treatment-resistant depression: response to ketamine and prediction of treatment outcome

March 21, 2017 / Depressive Disorders, Ketamine, Papers, Psychiatry & Medicine, Psychology / By / , , , , , ,

Abstract

A subset of patients with depression have elevated levels of inflammatory cytokines, and some studies demonstrate interaction between inflammatory factors and treatment outcome. However, most studies focus on only a narrow subset of factors in a patient sample. In the current study, we analyzed broad immune profiles in blood from patients with treatment-resistant depression (TRD) at baseline and following treatment with the glutamate modulator ketamine. Serum was analyzed from 26 healthy control and 33 actively depressed TRD patients free of antidepressant medication, and matched for age, sex and body mass index. All subjects provided baseline blood samples, and TRD subjects had additional blood draw at 4 and 24 h following intravenous infusion of ketamine (0.5 mg kg−1). Samples underwent multiplex analysis of 41 cytokines, chemokines and growth factors using quantitative immunoassay technology. Our a priori hypothesis was that TRD patients would show elevations in canonical pro-inflammatory cytokines; analyses demonstrated significant elevation of the pro-inflammatory cytokine interleukin-6. Further exploratory analyses revealed significant regulation of four additional soluble factors in patients with TRD. Several cytokines showed transient changes in level after ketamine, but none correlated with treatment response. Low pretreatment levels of fibroblast growth factor 2 were associated with ketamine treatment response. In sum, we found that patients with TRD demonstrate a unique pattern of increased inflammatory mediators, chemokines and colony-stimulating factors, providing support for the immune hypothesis of TRD. These patterns suggest novel treatment targets for the subset of patients with TRD who evidence dysregulated immune functioning.
Kiraly, D. D., Horn, S. R., Van Dam, N. T., Costi, S., Schwartz, J., Kim-Schulze, S., … & Iosifescu, D. V. (2017). Altered peripheral immune profiles in treatment-resistant depression: response to ketamine and prediction of treatment outcome. Translational psychiatry, 7(3), e1065. 10.1038/tp.2017.31
Link to full text

interested in becoming a trained psychedelic-assisted therapist?

Management of Psychedelic-Related Complications - Online Event - Nov 20th

REGISTER NOW