Antidepressant effects of ketamine and ECT: A pilot comparison

Shared effects of electroconvulsive shocks and ketamine on neuroplasticity: A systematic review of animal models of depression

Electroconvulsive shocks (ECS) and ketamine are antidepressant treatments with a relatively fast onset of therapeutic effects compared to conventional medication and psychotherapy. While the exact neurobiological mechanisms underlying the antidepressant response of ECS and ketamine are unknown, both interventions are associated with neuroplasticity. Restoration of neuroplasticity may be a shared mechanism underlying the antidepressant efficacy of these interventions. In this systematic review, literature of animal models of depression is summarized to examine the possible role of neuroplasticity in ECS and ketamine on a molecular, neuronal, synaptic and functional level, and specifically to what extent these mechanisms are shared between both interventions. The results highlight that hippocampal neurogenesis and brain-derived neurotrophic factor (BDNF) levels are consistently increased after ECS and ketamine. Moreover, both interventions positively affect glutamatergic neurotransmission, astrocyte and neuronal morphology, synaptic density, vasculature and functional plasticity. However, a small number of studies investigated these processes after ECS. Understanding the shared fundamental mechanisms of fast-acting antidepressants can contribute to the development of novel therapeutic approaches for patients with severe depression.

Ketamine versus electroconvulsive therapy for major depressive episode: An updated systematic review and non-inferiority meta-analysis

We conducted a systematic review and meta-analysis to investigate the comparative effectiveness of ketamine versus electroconvulsive therapy (ECT) for the treatment of major depressive episodes (MDEs). PubMed, EMBASE and Cochrane Library databases were systematically searched for randomized controlled trials (RCTs) comparing ketamine and ECT for MDE. The primary outcome was response rate, for which we prespecified a non-inferiority margin of -0.1, based on the largest and most recent RCT. Response was defined as a reduction of at least 50 % in the depression scale score. Six RCTs met the inclusion criteria, comprising 655 patients. In the overall population, ketamine was not non-inferior to ECT in response rate (RD -0.10; 95 % CI -0.26 to 0.05; p = 0.198; I2 = 72 %). The ECT group had a higher reduction in depression scores, but without difference in remission and relapse rates. Regarding safety outcomes, ketamine had better posttreatment cognition scores and reduced muscle pain rate compared with ECT, albeit with an increased rate of dissociative symptoms. In a subanalysis with only inpatients, ketamine was inferior to ECT in response rate (RD -0.15; 95 % CI -0.27 to -0.03; p = 0.014; I2 = 25 %), remission, and change in depression scores. These findings support the use of ECT over ketamine for inpatients. Further RCTs are warranted to clarify the comparative effect of these treatments for outpatients.

Physiotherapy for patients with depression: Recent research progress

Depression, a common mental illness, seriously affects the health of individuals and has deleterious effects on society. The prevention and treatment of depression has drawn the attention of many researchers and has become an important social issue. The treatment strategies for depression include drugs, psychotherapy, and physiotherapy. Drug therapy is ineffective in some patients and psychotherapy has treatment limitations. As a reliable adjuvant therapy, physiotherapy compensates for the shortcomings of drug and psychotherapy and effectively reduces the disease recurrence rate. Physiotherapy is more scientific and rigorous, its methods are diverse, and to a certain extent, provides more choices for the treatment of depression. Physiotherapy can relieve symptoms in many ways, such as by improving the levels of neurobiochemical molecules, inhibiting the inflammatory response, regulating the neuroendocrine system, and increasing neuroplasticity. Physiotherapy has biological effects similar to those of antidepressants and may produce a superimposed impact when combined with other treatments. This article summarizes the findings on the use of physiotherapy to treat patients with depression over the past five years. It also discusses several methods of physiotherapy for treating depression from the aspects of clinical effect, mechanism of action, and disadvantages, thereby serving as a reference for the in-depth development of physiotherapy research.

The efficacy of electroconvulsive therapy in adolescent major depressive disorder with suicidal ideation: A propensity score-matched, retrospective cohort study

BACKGROUND

More evidence is needed to validate the use of ECT in adolescent depression. This study aims to compare the effectiveness of electroconvulsive therapy (ECT) to conventional medication therapy for adolescents with major depression with suicidal ideation.

METHODS

In this retrospective cohort study, we reviewed inpatient records from the First Affiliated Hospital of Chongqing Medical University spanning December 2016 to June 2021. We focused on adolescents diagnosed with severe depression presenting with suicidal tendencies. To equalize baseline differences between patients, we used the one-to-one propensity score matching to match patients who received ECT treatment with those who did not. Multivariate regression analysis was utilized to adjust for potential confounders, and subgroup analyses and sensitivity analyses were conducted to verify the robustness of our findings.

RESULTS

Of the 626 patients in this study, 474 underwent ECT treatment while 152 received medication treatment, all aged between 10 and 18 years. Once matched, each group contained 143 patients. The ECT group demonstrated a significantly higher response rate and greater reductions in both Hamilton Depression Rating Scale and Hamilton Anxiety Scale scores (all P < 0.001). Additionally, the ECT group was more effective in reducing suicidal ideation, with fewer individuals retaining such ideation at discharge. In the multivariable regression analysis, both ECT treatment and shorter disease duration were independently linked to enhanced antidepressant efficacy. Subgroup analyses and sensitivity analyses verified the robustness of the main study effect.

CONCLUSIONS

For adolescents with major depressive disorder and suicidal ideation, combining ECT with pharmacotherapy is more effective than pharmacotherapy alone before medications reach full effect.

Research on clinical aspects of bipolar disorder: A review of Indian studies

Background

Bipolar disorder is one of the severe mental disorders that are associated with significant morbidity of the patients. Despite advancements in our understanding about the disorder, it remains a challenging proposition to treat bipolar disorder, largely since the prophylactic treatment of the disorder requires assessment of complex clinical algorithms. The revisions of the classificatory systems have also changed the conceptualization of the disorder. In this background, we conducted a review of the Indian studies conducted on the clinical aspects of bipolar disorder.

Methods

A narrative review was conducted with focus on the literature published from India. The databases searched included PubMed, Scopus, and Google Scholar, and articles published over the last 15 years by Indian authors were included for this review.

Results

In our review, we could access a substantial volume of research published from India. We could identify studies that catered to most of the relevant themes in bipolar disorder including epidemiology, etiology, comorbidities, stigma, disability, clinical course, cognitive profile, pathways to care, and recovery.

Conclusion

The research trajectory was in line with the research conducted elsewhere in the world. However, certain dissimilarities in terms of focus could also be observed. The possible reason behind this deviation could be the difference in clinical need and unique challenges faced in the management and rehabilitation of patients in bipolar disorder in Indian scenario.

A Comparison of the Efficacy and Adverse Effects of Ketamine and Electroconvulsive Therapy in the Management of Treatment-Resistant Depression: A Systematic Review

Ketamine has been repeatedly demonstrated to be an effective treatment in the management of patients with treatment-resistant depression (TRD). An important question is whether it is equally or more effective than the current gold standard of electroconvulsive therapy (ECT), as the adverse effects of ECT can lead to memory loss and neurocognitive deficits. A literature search was conducted for trials that directly compared the efficacy and adverse effects of ketamine and ECT via PubMed and Google Scholar. A total of 56 articles were identified with six included in this review. The studies included differed significantly in their quality and with differing levels of potential for bias. Ketamine has a more immediate effect when compared to ECT, but the antidepressant effects are shorter-lasting. Cognitive deficits were less pronounced in patients undergoing ketamine therapy. Many studies had a small number of participants and varied widely in the type of ECT used. Allocation bias seems likely in nonrandomized studies. Follow-up times were also short in some studies. The existing literature does not provide sufficient evidence to support the usage of ketamine over that of ECT for TRD, as remission rates were significantly higher over extended periods in ECT groups. Cognitive adverse effects were more pronounced in patients undergoing ECT. More high-quality randomized controlled trials (RCTs) directly comparing these two treatment modalities are required before drawing any firm conclusions.

A systematic review of the incidence of medical serious adverse events in sub-anesthetic ketamine treatment of psychiatric disorders

BACKGROUND

Limited published data exists that collates serious adverse outcomes involving ketamine as a psychiatric intervention. This systematic review assesses the reported incidence of medical serious adverse events (MSAEs), including but not limited to cardiovascular events, in patients receiving sub-anesthetic doses of ketamine for psychiatric disorders to guide practitioners during treatment planning, risk-benefit analyses, and the informed consent process.

METHODS

Pubmed database was searched for clinical trials of sub-anesthetic ketamine for psychiatric disorders in non-pregnant adult patients. Of the 2275 articles identified, 93 met inclusion criteria, over half of which were published in 2017 or later. Only studies that reported adverse events were included, and the incidence of MSAEs was calculated.

RESULTS

Of the 3756 participants who received at least one sub-anesthetic dose of ketamine, four participants experienced a MSAE, resulting in an incidence of approximately 0.1 % of individuals. The four MSAEs resolved without reported sequelae. Eighty-three percent of studies reported screening for medical illness and exclusion of high-risk patients. There were no serious cardiac adverse events or deaths observed in any participants; however, most trials' study designs excluded those with high cardiovascular complication risk.

LIMITATIONS

Most studies were small, underpowered for detecting rare MSAEs, at potential high-risk of bias of non-report of MSAEs, and limited mostly to intranasal and intravenous routes.

CONCLUSIONS

Findings suggest that with basic medical screening there is a very low incidence of MSAEs including adverse cardiac or cerebrovascular events in individuals receiving sub-anesthetic ketamine for psychiatric disorders.

Efficacy and adverse effects of ketamine versus electroconvulsive therapy for major depressive disorder: A systematic review and meta-analysis

BACKGROUND

ECT is considered the fastest and most effective treatment for TRD. Ketamine seems to be an attractive alternative due to its rapid-onset antidepressant effects and impact on suicidal thoughts. This study aimed to compare efficacy and tolerability of ECT and ketamine for different depression outcomes (PROSPERO/CRD42022349220).

METHODS

We searched MEDLINE, Web of Science, Embase, PsycINFO, Google Scholar, Cochrane Library and trial registries, which were the ClinicalTrials.gov and the World Health Organization's International Clinical Trials Registry Platform, without restrictions on publication date.

SELECTION CRITERIA

randomized controlled trials or cohorts comparing ketamine versus ECT in patients with TRD.

RESULTS

Eight studies met the inclusion criteria (of 2875 retrieved). Random-effects models comparing ketamine and ECT regarding the following outcomes were conducted: a) reduction of depressive symptoms severity through scales, g = -0.12, p = 0.68; b) response to therapy, RR = 0.89, p = 0.51; c) reported side-effects: dissociative symptoms, RR = 5.41, p = 0.06; nausea, RR = 0.73, p = 0.47; muscle pain, RR = 0.25, p = 0.02; and headache, RR = 0.39, p = 0.08. Influential & subgroup analyses were performed.

LIMITATIONS

Methodological issues with high risk of bias in some of the source material, reduced number of eligible studies with high in-between heterogeneity and small sample sizes.

CONCLUSION

Our study showed no evidence to support the superiority of ketamine over ECT for severity of depressive symptoms and response to therapy. Regarding side effects, there was a statistically significant decreased risk of muscle pain in patients treated with ketamine compared to ECT.

Ketamine vs Electroconvulsive Therapy for Major Depressive Episode: A Systematic Review and Meta-analysis

Importance

The relative efficacy of ketamine and electroconvulsive therapy (ECT) in adults with major depressive episode (MDE) needs clarification.

Objective

To compare depression rating outcomes with ketamine vs ECT in adults with MDE and to compare response and remission rates, number of sessions to response and remission, and adverse effects.

Data Sources

Two investigators independently systematically searched MEDLINE, ScienceDirect, and Google Scholar databases using a combination of relevant Medical Subject Headings terms and free-text keywords from database inception through May 15, 2022, to identify relevant English-language trials.

Study Selection

Parallel-group randomized clinical trials (RCTs).

Data Extraction and Synthesis

Two investigators independently extracted data and assessed risk of bias. One-week posttreatment outcomes were pooled as standardized mean difference (SMD; Hedges g) for continuous outcomes and risk ratio (RR) for categorical outcomes in random-effects meta-analyses.

Main Outcomes and Measures

Efficacy outcomes were 1-week (or nearest) posttreatment depression ratings, 1-week (or nearest) study-defined response and remission rates, and number of sessions to treatment response and remission. Safety outcomes were reported adverse effects.

Results

Five trials (ketamine group: n = 141; ECT group: n = 137) were meta-analyzed. The overall pooled SMD for posttreatment depression ratings was -0.39 (95% CI, -0.81 to 0.02; I2 = 45%; 5 RCTs). For this efficacy outcome, in a sensitivity analysis of methodologically stronger trials, ECT was superior to ketamine (SMD, -0.45; 95% CI, -0.75 to -0.14; I2 = 6%; 2 RCTs). ECT was also superior to ketamine for study-defined response (RR, 1.27; 95% CI, 1.06-1.53; I2 = 0%; 3 RCTs) and remission (RR, 1.43; 95% CI, 1.12-1.82; I2 = 0%; 2 RCTs) rates. No significant differences were noted between groups for number of sessions to response and remission and for cognitive outcomes. Key limitations were small number of studies, limited sample size, and high risk of bias in all trials.

Conclusion and Relevance

The findings of this systematic review and meta-analysis suggest an efficacy advantage for ECT over ketamine in adults with MDE. These conclusions are tempered by the small number and size of existing trials.

Is depression the missing link between inflammatory mediators and cancer?

Patients with cancer are at greater risk of developing depression in comparison to the general population and this is associated with serious adverse effects, such as poorer quality of life, worse prognosis and higher mortality. Although the relationship between depression and cancer is now well established, a common underlying pathophysiological mechanism between the two conditions is yet to be elucidated. Existing theories of depression, based on monoamine neurotransmitter system dysfunction, are insufficient as explanations of the disorder. Recent advances have implicated neuroinflammatory mechanisms in the etiology of depression and it has been demonstrated that inflammation at a peripheral level may be mirrored centrally in astrocytes and microglia serving to promote chronic levels of inflammation in the brain. Three major routes to depression in cancer in which proinflammatory mediators are implicated, seem likely. Activation of the kynurenine pathway involving cytokines, increases tryptophan catabolism, resulting in diminished levels of serotonin which is widely acknowledged as being the hallmark of depression. It also results in neurotoxic effects on brain regions thought to be involved in the evolution of major depression. Proinflammatory mediators also play a crucial role in impairing regulatory glucocorticoid mediated feedback of the hypothalamic-pituitary-adrenal axis, which is activated by stress and considered to be involved in both depression and cancer. The third route is via the glutamatergic pathway, whereby glutamate excitotoxicity may lead to depression associated with cancer. A better understanding of the mechanisms underlying these dysregulated and other newly emerging pathways may provide a rationale for therapeutic targeting, serving to improve the care of cancer patients.

Efficacy and Safety of Ketamine vs Electroconvulsive Therapy Among Patients With Major Depressive Episode: A Systematic Review and Meta-analysis

Importance

Whether ketamine is as effective as electroconvulsive therapy (ECT) among patients with major depressive episode remains unknown.

Objective

To systematically review and meta-analyze data about clinical efficacy and safety for ketamine and ECT in patients with major depressive episode.

Data Sources

PubMed, MEDLINE, Cochrane Library, and Embase were systematically searched using Medical Subject Headings (MeSH) terms and text keywords from database inception through April 19, 2022, with no language limits. Two authors also manually and independently searched all relevant studies in US and European clinical trial registries and Google Scholar.

Study Selection

Included were studies that involved (1) a diagnosis of depression using standardized diagnostic criteria, (2) intervention/comparator groups consisting of ECT and ketamine, and (3) depressive symptoms as an efficacy outcome using standardized measures.

Data Extraction and Synthesis

Data extraction was completed independently by 2 extractors and cross-checked for errors. Hedges g standardized mean differences (SMDs) were used for improvement in depressive symptoms. SMDs with corresponding 95% CIs were estimated using fixed- or random-effects models. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed.

Main Outcomes and Measures

Efficacy outcomes included depression severity, cognition, and memory performance. Safety outcomes included serious adverse events (eg, suicide attempts and deaths) and other adverse events.

Results

Six clinical trials comprising 340 patients (n = 162 for ECT and n = 178 for ketamine) were included in the review. Six of 6 studies enrolled patients who were eligible to receive ECT, 6 studies were conducted in inpatient settings, and 5 studies were randomized clinical trials. The overall pooled SMD for depression symptoms for ECT when compared with ketamine was -0.69 (95% CI, -0.89 to -0.48; Cochran Q, P = .15; I2 = 39%), suggesting an efficacy advantage for ECT compared with ketamine for depression severity. Significant differences were not observed between groups for studies that assessed cognition/memory or serious adverse events. Both ketamine and ECT had unique adverse effect profiles (ie, ketamine: lower risks for headache and muscle pain; ECT: lower risks for blurred vision, vertigo, diplopia/nystagmus, and transient dissociative/depersonalization symptoms). Limitations included low to moderate methodological quality and underpowered study designs.

Conclusions and Relevance

Findings from this systematic review and meta-analysis suggest that ECT may be superior to ketamine for improving depression severity in the acute phase, but treatment options should be individualized and patient-centered.

Changes in adipokine concentrations in antidepressant-resistant bipolar depression after ketamine infusion and electroconvulsive therapy

OBJECTIVES

This study attempts to assess the concentration of two opposite-acting adipokines (anti-inflammatory adiponectin and pro-inflammatory resistin) in antidepressant-resistant patients undergoing ketamine infusion (KI) and electroconvulsive therapy (ECT).

METHODS

The study group comprised 52 patients hospitalised due to episodes of depression in the course of bipolar disorders. The Hamilton depression scale was used to assess the intensity of the depression symptoms before starting therapy and one day after its completion. The serum concentration of adipokines was determined before and after the therapeutic intervention using an ELISA method.

RESULTS

Baseline adipokine levels differed between patients receiving KI and ECT therapy. Regardless of the procedure used, these levels changed after treatment, with the nature of these changes being different. In the case of KI, the adiponectin levels increased, and resistin levels decreased. In contrast, after ECT, the concentrations of both adipokines decreased. Changes in adipokine concentrations correlated with improvement in mental status, as assessed by the Hamilton Rating Scale, type of bipolar disorder, and gender.

CONCLUSIONS

Adipokines remain interesting candidate biomarkers in assessing the state and course of the disease depending on the therapeutic procedure applied. However, the relatively small study group and limited original research available for discussion justify further investigation.

Ketamine in depression and electroconvulsive therapy

PURPOSE OF REVIEW

The antidepressant effect of subanesthetic doses of ketamine was recognized 20 years ago. This review briefly summarizes the current understanding of the antidepressant mechanisms and the available clinical research on the use of racemic ketamine and enantiomer esketamine for depression.

RECENT FINDINGS

The antidepressant effect of subanesthetic doses of ketamine is currently considered to be predominantly mediated by improved neuroplasticity in cortico-limbic areas in the brain. Single dose of 0.5 mg/kg of ketamine infused intravenously over 40 min, or single intranasal dose of esketamine cause rapid antidepressant and antisuicidal effects within hours of administration, and the antidepressant effect may last up to a week. Repeated administration of nasal spray esketamine is considered to prevent relapse of depression. Longitudinal studies are currently insufficient. When used in various doses for anesthetic induction for electroconvulsive therapy, ketamine improves seizure quality and may possibly diminish posttherapy cognitive impairment.

SUMMARY

A rapid onset antidepressive effect of ketamine and esketamine has been proven conclusively. The results of extensive basic science research of the mechanism of action of low-dose ketamine doses has led to an alternative hypothesis of the pathophysiology of depression and the development of a novel neurotrophic concept of depression. Further longitudinal studies are warranted to determine the safety and efficacy of repeated administration of ketamine and its analogs to prevent relapse and recurrence of depression.

Ketamine and other glutamate receptor modulators for depression in adults with unipolar major depressive disorder

BACKGROUND

Many studies have recently been conducted to assess the antidepressant efficacy of glutamate modification in mood disorders. This is an update of a review first published in 2015 focusing on the use of glutamate receptor modulators in unipolar depression.

OBJECTIVES

To assess the effects - and review the acceptability and tolerability - of ketamine and other glutamate receptor modulators in alleviating the acute symptoms of depression in people with unipolar major depressive disorder.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Embase and PsycINFO all years to July 2020.  We did not apply any restrictions to date, language or publication status.

SELECTION CRITERIA

Double- or single-blinded randomised controlled trials (RCTs) comparing ketamine, memantine, esketamine or other glutamate receptor modulators with placebo (pill or saline infusion), other active psychotropic drugs, or electroconvulsive therapy (ECT) in adults with unipolar major depression.

DATA COLLECTION AND ANALYSIS

Three review authors independently identified studies, assessed trial quality and extracted data. The primary outcomes were response rate (50% reduction on a standardised rating scale) and adverse events. We decided a priori to measure the efficacy outcomes at different time points and run sensitivity/subgroup analyses. Risk of bias was assessed using the Cochrane tool, and certainty of the evidence was assessed using GRADE.

MAIN RESULTS

Thirty-one new studies were identified for inclusion in this updated review. Overall, we included 64 studies (5299 participants) on ketamine (31 trials), esketamine (9), memantine (5), lanicemine (4), D-cycloserine (2), Org26576 (2), riluzole (2), atomoxetine (1), basimglurant (1), citicoline (1), CP-101,606 (1), decoglurant (1), MK-0657 (1), N-acetylcysteine (1), rapastinel (1), and sarcosine (1). Forty-eight studies were placebo-controlled, and 48 were two-arm studies. The majority of trials defined an inclusion criterion for the severity of depressive symptoms at baseline: 29 at least moderate depression; 17 severe depression; and five mild-to-moderate depression. Nineteen studies recruited only patients with treatment-resistant depression, defined as inadequate response to at least two antidepressants. The majority of studies investigating ketamine administered as a single dose, whilst all of the included esketamine studies used a multiple dose regimen (most frequently twice a week for four weeks). Most studies looking at ketamine used intravenous administration, whilst the majority of esketamine trials used intranasal routes. The evidence suggests that ketamine may result in an increase in response and remission compared with placebo at 24 hours odds ratio (OR) 3.94, 95% confidence interval (CI) 1.54 to 10.10; n = 185, studies = 7, very low-certainty evidence). Ketamine may reduce depression rating scale scores over placebo at 24 hours, but the evidence is very uncertain (standardised mean difference (SMD) -0.87, 95% CI -1.26 to -0.48; n = 231, studies = 8, very low-certainty evidence). There was no difference in the number of participants assigned to ketamine or placebo who dropped out for any reason (OR 1.25, 95% CI 0.19 to 8.28; n = 201, studies = 6, very low-certainty evidence). When compared with midazolam, the evidence showed that ketamine increases remission rates at 24 hours (OR 2.21, 95% CI 0.67 to 7.32; n = 122,studies = 2, low-certainty evidence). The evidence is very uncertain about the response efficacy of ketamine at 24 hours in comparison with midazolam, and its ability to reduce depression rating scale scores at the same time point (OR 2.48, 95% CI 1.00 to 6.18; n = 296, studies = 4,very low-certainty evidence). There was no difference in the number of participants who dropped out of studies for any reason between ketamine and placebo (OR 0.33, 95% CI 0.05 to 2.09; n = 72, studies = 1, low-certainty evidence). Esketamine treatment likely results in a large increase in participants achieving remission at 24 hours compared with placebo (OR 2.74, 95% CI 1.71 to 4.40; n = 894, studies = 5, moderate-certainty evidence). Esketamine probably results in decreases in depression rating scale scores at 24 hours compared with placebo (SMD -0.31, 95% CI -0.45 to -0.17; n = 824, studies = 4, moderate-certainty evidence). Our findings show that esketamine increased response rates, although this evidence is uncertain (OR 2.11, 95% CI 1.20 to 3.68; n = 1071, studies = 5, low-certainty evidence). There was no evidence that participants assigned to esketamine treatment dropped out of trials more frequently than those assigned to placebo for any reason (OR 1.58, 95% CI 0.92 to 2.73; n = 773, studies = 4,moderate-certainty evidence). We found very little evidence for the remaining glutamate receptor modulators. We rated the risk of bias as low or unclear for most domains, though lack of detail regarding masking of treatment in the studies reduced our certainty in the effect for all outcomes.

AUTHORS' CONCLUSIONS

Our findings show that ketamine and esketamine may be more efficacious than placebo at 24 hours. How these findings translate into clinical practice, however, is not entirely clear. The evidence for use of the remaining glutamate receptor modulators is limited as very few trials were included in the meta-analyses for each comparison and the majority of comparisons included only one study. Long term non-inferiority RCTs comparing repeated ketamine and esketamine, and rigorous real-world monitoring are needed to establish comprehensive data on safety and efficacy.

Is ketamine an appropriate alternative to ECT for patients with treatment resistant depression? A systematic review

OBJECTIVE

Ketamine has repeatedly shown to have rapid and robust antidepressant effects in patients with treatment resistant depression (TRD). An important question is whether ketamine is as effective and safe as the current gold standard electroconvulsive therapy (ECT).

METHODS

The literature was searched for trials comparing ketamine treatment with ECT for depression in the Pubmed/MEDLINE database and Cochrane Trials Library.

RESULTS

A total of 137 manuscripts were identified, 6 articles were included in this review. Overall quality of the included studies was diverse with relevant risk of bias for some of the studies. Results suggest that ketamine treatment might give faster but perhaps less durable antidepressant effects. Side effects differed from ECT, in particular less cognitive impairment was apparent in ketamine treatment.

LIMITATIONS

The included studies have limited sample sizes, use different treatment protocols and in most trials, longer term follow up is lacking. Furthermore, allocation bias appears likely in the non-randomized trials.

CONCLUSIONS

Current available literature does not yet provide convincing evidence to consider ketamine as an equally effective treatment alternative to ECT in patients with TRD. There are indications for a more favourable short term cognitive side effect profile after ketamine treatment. Methodologically well-designed studies with larger sample sizes and longer follow up duration are warranted.