Feasibility, safety, and preliminary efficacy of Low Amplitude Seizure Therapy (LAP-ST): A proof of concept clinical trial in man

How electroconvulsive therapy works in the treatment of depression: is it the seizure, the electricity, or both?

We have known for nearly a century that triggering seizures can treat serious mental illness, but what we do not know is why. Electroconvulsive Therapy (ECT) works faster and better than conventional pharmacological interventions; however, those benefits come with a burden of side effects, most notably memory loss. Disentangling the mechanisms by which ECT exerts rapid therapeutic benefit from the mechanisms driving adverse effects could enable the development of the next generation of seizure therapies that lack the downside of ECT. The latest research suggests that this goal may be attainable because modifications of ECT technique have already yielded improvements in cognitive outcomes without sacrificing efficacy. These modifications involve changes in how the electricity is administered (both where in the brain, and how much), which in turn impacts the characteristics of the resulting seizure. What we do not completely understand is whether it is the changes in the applied electricity, or in the resulting seizure, or both, that are responsible for improved safety. Answering this question may be key to developing the next generation of seizure therapies that lack these adverse side effects, and ushering in novel interventions that are better, faster, and safer than ECT.

Electroconvulsive Therapy: Mechanisms of Action, Clinical Considerations, and Future Directions

LEARNING OBJECTIVES

• Outline and discuss the fundamental physiologic, cellular, and molecular mechanisms of ECT to devise strategies to optimize therapeutic outcomes• Summarize the overview of ECT, its efficacy in treating depression, the known effects on cognition, evidence of mechanisms, and future directions.

ABSTRACT

Electroconvulsive therapy (ECT) is the most effective treatment for a variety of psychiatric illnesses, including treatment-resistant depression, bipolar depression, mania, catatonia, and clozapine-resistant schizophrenia. ECT is a medical and psychiatric procedure whereby electrical current is delivered to the brain under general anesthesia to induce a generalized seizure. ECT has evolved a great deal since the 1930s. Though it has been optimized for safety and to reduce adverse effects on cognition, issues persist. There is a need to understand fundamental physiologic, cellular, and molecular mechanisms of ECT to devise strategies to optimize therapeutic outcomes. Clinical trials that set out to adjust parameters, electrode placement, adjunctive medications, and patient selection are critical steps towards the goal of improving outcomes with ECT. This narrative review provides an overview of ECT, its efficacy in treating depression, its known effects on cognition, evidence of its mechanisms, and future directions.

Trajectories of Efficacy and Cognitive Function During Electroconvulsive Therapy Course in Young Adults with Treatment-Resistant Depression

Objective

Little is known about the effectiveness and cognitive side-effects of electroconvulsive therapy (ECT) in young adults with treatment-resistant depression (TRD). The primary aim of this prospective longitudinal observational trial was to examine the clinical features and cognitive outcomes of young adults with TRD undergoing ECT.

Methods

Changes in depressive symptoms and objective and subjective cognitive function were assessed using repeated evaluation at baseline, after each ECT session, and at one-month follow-up using the Montgomery-Äsberg Depression Rating Scale (MADRS) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Forward Digital Span Test (FDST), and part of the Columbia Subjective Side Effects Schedule.

Results

Of 41 inpatients, 35 (85.4%) and 12 (29.3%) met the criteria for response and remission after ECT, respectively. The greatest clinical improvements occurred during the first 3-4 ECT sessions. While 34 patients reported subjective cognitive impairment increased with ECT, immediate and delayed memory (RBANS) significantly increased after ECT, consistent with FDST results. Objective cognition significantly improved during follow-up, but subjective cognition remained impaired.

Conclusion

ECT is effective in young adults with TRD. Although subjective cognitive impairment increased during treatment, objective cognitive impairments were not observed.

Electroconvulsive Treatment Utilization for Inpatient Management of Catatonia in Adolescents With Schizophrenia Spectrum Disorders

OBJECTIVE

The aim of this study was to determine rates of electroconvulsive therapy (ECT) use for catatonia in schizophrenia spectrum disorders, stratified by patient demographics and hospital characteristics, and its impact on inpatient length of stay and cost.

METHODS

We found 155 adolescents (aged 12-18 years) with principal discharge diagnosis of schizophrenia spectrum disorders with catatonia from the National Inpatient Sample. They were subgrouped into ECT (n = 20) and non-ECT (n = 135) groups. We used descriptive statistics to evaluate the utilization of ECT for catatonia and independent-sample t test for continuous variables with statistical significance at P ≤ 0.05.

RESULTS

The overall utilization rate of ECT in adolescents for catatonia was 12.9%. A high rate of ECT use was evident for Whites (30.8%) compared with the other race/ethnicities and also was seen in private health insurance beneficiaries (20%). The rate of ECT use varied by the region, with highest for the Northeast (20%), followed by the South (18.2%), and the West (14.3%). Adolescent inpatients with catatonia in public and teaching type, and large bed-size hospitals were more likely to receive ECT than their counterparts. The mean number of ECT sessions required during the inpatient stay was 5.2 (range, 1-15), and the mean number of days from admission to initial ECT was 2.5 (range, 0-6).

CONCLUSIONS

Electroconvulsive therapy is used for approximately only 13% of adolescents with catatonia when comorbid schizophrenia spectrum disorders are present, suggesting that many patients may not get evidence-based treatment. Future studies in this area are needed.

Electroconvulsive therapy, electric field, neuroplasticity, and clinical outcomes

Electroconvulsive therapy (ECT) remains the gold-standard treatment for patients with depressive episodes, but the underlying mechanisms for antidepressant response and procedure-induced cognitive side effects have yet to be elucidated. Such mechanisms may be complex and involve certain ECT parameters and brain regions. Regarding parameters, the electrode placement (right unilateral or bitemporal) determines the geometric shape of the electric field (E-field), and amplitude determines the E-field magnitude in select brain regions (e.g., hippocampus). Here, we aim to determine the relationships between hippocampal E-field strength, hippocampal neuroplasticity, and antidepressant and cognitive outcomes. We used hippocampal E-fields and volumes generated from a randomized clinical trial that compared right unilateral electrode placement with different pulse amplitudes (600, 700, and 800 mA). Hippocampal E-field strength was variable but increased with each amplitude arm. We demonstrated a linear relationship between right hippocampal E-field and right hippocampal neuroplasticity. Right hippocampal neuroplasticity mediated right hippocampal E-field and antidepressant outcomes. In contrast, right hippocampal E-field was directly related to cognitive outcomes as measured by phonemic fluency. We used receiver operating characteristic curves to determine that the maximal right hippocampal E-field associated with cognitive safety was 112.5 V/m. Right hippocampal E-field strength was related to the whole-brain ratio of E-field strength per unit of stimulation current, but this whole-brain ratio was unrelated to antidepressant or cognitive outcomes. We discuss the implications of optimal hippocampal E-field dosing to maximize antidepressant outcomes and cognitive safety with individualized amplitudes.

Need for Standardization of Measurement of Time to Reorientation as a Predictor of Cognitive Adverse Effects of Electroconvulsive Therapy

ABSTRACT

Testing for time to reorientation (TRO) after electroconvulsive therapy (ECT) has been one of the most predictive measures for cognitive adverse effects of ECT. However, measuring TRO varies between clinical trials, and there is no standardized approach on its measurement between studies. The objective of this report is to systematically review the literature on the different ways of measuring TRO. This would be a first step to establish a consensus on a standard method for TRO. We performed a systematic literature review from 1968 to October 2019 for clinical trials with a sample size of more than 50 and published in English that describe measures of TRO. We searched both PubMed and Web of Science databases. The literature search generated 12 clinical trials, which met the inclusion criteria. Studies measured TRO using 3-, 5-, or 10-item questionnaires. Most studies measured full orientation as answering 4/5 questions. Other studies smaller than 50 required 14/14 items to be answered correctly. There was wide variation between studies on how often and when orientation questions were initiated. These factors have obvious implications to the results and interpretation of the ECT literature.There was no clear consensus on measuring TRO in a uniform fashion. Research and clinical care would benefit from a standardized approach to measuring TRO. Measuring TRO using a 4/5 method seems the most common and quickest way, whereas using a 14/14 method seems to be the most rigorous and sensitive to change in trials.

Electric field strength induced by electroconvulsive therapy is associated with clinical outcome

The clinical effect of electroconvulsive therapy (ECT) is mediated by eliciting a generalized seizure, which is achieved by applying electrical current to the head via scalp electrodes. The anatomy of the head influences the distribution of current flow in each brain region. Here, we investigated whether individual differences in simulated local electrical field strength are associated with ECT efficacy. We modeled the electric field of 67 depressed patients receiving ECT. Patient's T1 magnetic resonance images were segmented, conductivities were assigned to each tissue and the finite element method was used to solve for the electric field induced by the electrodes. We investigated the correlation between modelled electric field and ECT outcome using voxel-wise general linear models. The difference between bilateral (BL) and right unilateral (RUL) electrode placement was striking. Even within electrode configuration, there was substantial variability between patients. For the modeled BL placement, stronger electric field strengths appeared in the left hemisphere and part of the right temporal lobe. Importantly, a stronger electric field in the temporal lobes was associated with less optimal ECT response in patients treated with BL-ECT. No significant differences in electric field distributions were found between responders and non-responders to RUL-ECT. These results suggest that overstimulation of the temporal lobes during BL stimulation has negative consequences on treatment outcome. If replicated, individualized pre-ECT computer-modelled electric field distributions may inform the development of patient-specific ECT protocols.

Electroconvulsive Therapy Pulse Amplitude and Clinical Outcomes

INTRODUCTION

Electroconvulsive therapy (ECT) pulse amplitude, which determines the induced electric field magnitude in the brain, is currently set at 800-900 milliamperes (mA) on modern ECT devices without any clinical or scientific rationale. The present study assessed differences in depression and cognitive outcomes for three different pulse amplitudes during an acute ECT series. We hypothesized that the lower amplitudes would maintain the antidepressant efficacy of the standard treatment and reduce the risk of neurocognitive impairment.

METHODS

This double-blind investigation randomized subjects to three treatment arms: 600, 700, and 800 mA (active comparator). Clinical, cognitive, and imaging assessments were conducted pre-, mid- and post-ECT. Subjects had a diagnosis of major depressive disorder, age range between 50 and 80 years, and met clinical indication for ECT.

RESULTS

The 700 and 800 mA arms had improvement in depression outcomes relative to the 600 mA arm. The amplitude groups showed no differences in the primary cognitive outcome variable, the Hopkins Verbal Learning Test-Revised (HVLT-R) retention raw score. However, secondary cognitive outcomes such as the Delis Kaplan Executive Function System Letter and Category Fluency measures demonstrated cognitive impairment in the 800 mA arm.

DISCUSSION

The results demonstrated a dissociation of depression (higher amplitudes better) and cognitive (lower amplitudes better) related outcomes. Future work is warranted to elucidate the relationship between amplitude, electric field, neuroplasticity, and clinical outcomes.

Double-Blinded Randomized Pilot Clinical Trial Comparing Cognitive Side Effects of Standard Ultra-Brief Right Unilateral ECT to 0.5 A Low Amplitude Seizure Therapy (LAP-ST)

BACKGROUND

Concerns over cognitive side effects (CSE) of electroconvulsive therapy (ECT) still limit its broader usage for treatment-resistant depression (TRD). The objectives of this study were to (1) examine the CSE of Low Amplitude Seizure Therapy (LAP-ST) at 0.5 A compared to Ultra-brief Right Unilateral (UB-RUL) ECT using Time to Reorientation (TRO) as the main acute primary outcome, and (2) to compare effects on depressive symptoms between the two treatment groups.

METHODS

Participants were referred for ECT, consented for the study, and were randomized to a course of LAP-ST or standard UB-RUL ECT. TRO and depression were measured by the Montgomery-Åsberg Depression Rating Scale (MADRS).

RESULTS

Eleven patients consented. Of these, eight with a current major depressive episode (MDE) of unipolar or bipolar disorders were randomized. TRO was faster for the LAP-ST (mean = 6.8 min; SE = 4.9) than standard RUL ECT (mean = 15.5 min; SE = 6.5). Depression improved similarly in the two arms of the study from baseline (MADRS: LAP-ST = 41.0; SE = 2.0, RUL = 39.0; SE = 3.8) to endpoint (MADRS score: LAP-ST = 8.0; SE7.2, RUL = 9.5; SE = 3.8).

CONCLUSIONS

This pilot, randomized and blinded clinical trial, suggests that the LAP-ST (at 0.5 A) has faster reorientation and possibly lower CSE compared to standard RUL-UB ECT. Caution is advised in interpreting these results due to the small sample size of this pilot study. Thus, future studies with similar design are warranted for replicating these findings.

Treating Posttraumatic Stress Disorder Symptoms With Low Amplitude Seizure Therapy (LAP-ST) Compared With Standard Right Unilateral Electroconvulsive Therapy: A Pilot Double-Blinded Randomized Clinical Trial

OBJECTIVES

An important barrier to further studying electroconvulsive therapy (ECT) in posttraumatic stress disorder (PTSD) is the cognitive adverse effects. However, recent data suggest that low amplitude seizure therapy (LAP-ST) has no or minimal cognitive adverse effects. The aims of this report were to examine the efficacy of LAP-ST in PTSD and to compare LAP-ST with standard right unilateral (RUL) ECT using a pilot randomized clinical trial.

METHODS

Patients were randomized to LAP-ST or RUL ECT. Posttraumatic stress disorder was assessed using clinical interview based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and symptom severity with PTSD Checklist (PCL). The scores pertaining to PCL were analyzed using descriptive analysis for this pilot study.

RESULTS

Eleven patients consented to be enrolled. Seven were randomly allocated to LAP-ST or RUL ECT. Five completed the study and had completed PCL before and after the course. In both groups, PTSD symptoms showed fast improvement. The effect size of improvement seems promising. The mean baseline PCL score for patients in the LAP-ST group was 42.5 (SD = 16.26) and the mean end point PCL score after treatment was 31 (SD = 15.56). The mean baseline PCL score for patients in the standard RUL ECT group was 64.7 (SD = 1.15) and the mean end point was 41 (SD = 15.62).

CONCLUSIONS

Both LAP-ST and standard RUL ECT showed reduction in PTSD symptoms with fast improvement. This first PTSD LAP-ST study adds support to the prior LAP-ST proof-of-concept clinical trial that LAP-ST can produce effective therapeutic outcomes. Replication of this trial is warranted in larger clinical trials (ClinicalTrials.gov ID: NCT02583490).

[Brain stimulation for the selective treatment of schizophrenia symptom domains : Non-invasive and invasive concepts]

Given that one third of patients with schizophrenia (SZ) only show limited response to established treatments, alternative therapeutic strategies such as non-invasive/invasive brain stimulation approaches have emerged as an adjunctive treatment option for distinct SZ symptom domains (e.g. acoustic hallucinations, negative/positive symptoms and cognitive impairment). Taking comparative interventional studies and standardized technical parameters into consideration, current meta-analyses indicate that adjunctive electroconvulsive therapy, repetitive transcranial magnetic stimulation and transcranial direct current stimulation have a positive effect. Invasive deep brain stimulation and MR-guided ultrasound brain ablation procedures represent treatment modalities that are currently being clinically tested. Complementary pre-interventional screening approaches (e.g. electrophysiology, neuroimaging and molecular inflammatory profiling) have been recommended in order to identify symptom-tailored predictive measures for diagnosis and treatment.

Electroconvulsive therapy electrode placement for bipolar state-related targeted engagement

Background

Electroconvulsive therapy (ECT) is an effective treatment for all bipolar states. However, ECT remains underutilized, likely stemming from stigma and the risk of neurocognitive impairment. Neuroimaging research has identified state-specific areas of aberrant brain activity that may serve as targets for therapeutic brain stimulation. Electrode placement determines the geometry of the electric field and can be either non-focal (bitemporal) or more focal (right unilateral or bifrontal). Previous research has shown that electrode placement can impact clinical and cognitive outcomes independent of seizure activity. This review critically examines the evidence that focal (unilateral or bifrontal) electrode placements target specific aberrant circuitry in specific bipolar states to optimize clinical outcomes. We hypothesize that optimal target engagement for a bipolar state will be associated with equivalent efficacy relative to bitemporal non-focal stimulation with less neurocognitive impairment.

Methods

We performed a literature search in the PubMed database. Inclusion criteria included prospective, longitudinal investigations during the ECT series with specific electrode placements within a bipolar state from 2000 to 2018.

Results

We identified investigations that met our inclusion criteria with bipolar mania (n = 6), depression (n = 6), mixed (n = 3) and catatonia (n = 1) states. These studies included clinical outcomes and several included cognitive outcomes, which were discussed separately.

Conclusions

While the heterogeneity of the studies makes comparisons difficult, important patterns included the reduced cognitive side effects, faster rate of response, and equivalent efficacy rates of the focal electrode placements (right unilateral and bifrontal) when compared to non-focal (bitemporal) placement. Further avenues for research include more robust cognitive assessments to separate procedure-related and state-related impairment. In addition, future studies could investigate novel electrode configurations with more specific target engagement for different bipolar states.

Magnitude of Reduction and Speed of Remission of Suicidality for Low Amplitude Seizure Therapy (LAP-ST) Compared to Standard Right Unilateral Electroconvulsive Therapy: A Pilot Double-Blinded Randomized Clinical Trial

Background: Although treatment guidelines support use of electroconvulsive therapy (ECT) for acute suicidality, it is associated with cognitive side effects. The effect of Low Amplitude Seizure Therapy (LAP-ST) on suicidality is unknown. Our prior precision LAP-ST (pLAP-ST) performing titrating in the current domain has provided initial proof of concept data in humans of its advantage in terms of reduction of cognitive side effects. The aims of this report are to: 1) compare LAP-ST (at 500mA) versus standard Right Unilateral (RUL) ECT (at 900 mA) in terms of magnitude of remission of suicidality in a randomized allocation and 2) compare the speed of remission of suicidality between LAP-ST versus RUL ECT. Methods: Patients were randomized to either LAP-ST or RUL ECT. The scores pertaining to the suicidal ideation (SI) item on the Montgomery-Åsberg Depression Rating Scale (MADRS) were analyzed using descriptive analysis and no confirmatory statistical analysis was performed due to a priori sample size limitations for this pilot study. SI item remission was defined as 2 or below on this item. Results: Eleven patients with major depressive episode (MDE) of mainly unipolar or bipolar disorders signed consent. Of these, 7 were eligible and were randomized and included in the analysis; all were actively suicidal at baseline (suicide item above 2), except 1 patient who had suicide item at 2 in the RUL ECT group. Suicidality remitted on average by session 3 and remission occurred for all patients by session 4. The SI mean score improvement from baseline to endpoint for LAP-ST was 5.1 and for RUL ECT was 3.0. Conclusions: LAP-ST has larger effect size and speed of remission of suicidality compared to standard RUL ECT. Future studies are warranted for replicating these findings. (ClinicalTrials.gov ID: NCT02583490).

Auditory verbal hallucinations in schizophrenia: current perspectives in brain stimulation treatments

PURPOSE

This review reports the current perspectives of brain stimulation techniques in the treatment of auditory verbal hallucinations (AVH) in schizophrenia.

METHODS

A systematic search of the literature in the PubMed database revealed that the most studied techniques are noninvasive techniques (NIBS), including electroconvulsive therapy (ECT), transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS).

RESULTS

The results showed that ECT could have great clinical efficacy but is currently underused in practice perhaps due to the costs associated with its limited implementation and potential associated risks. tDCS is still poorly studied and does not demonstrate sufficiently homogeneous or conclusive results yet to prove its efficacy in the treatment of AVH. However, its safe and simple implementation allows us to recommend it to patients who are refractory to other stimulation techniques. Finally, rTMS seems to be the most efficacious NIBS to offer patients with persistent AVH as an add-on therapeutic strategy. Its implementation has a non negligible cost but can be performed by a single practitioner. Great evolution in these techniques with technological progress, robotics and computer science are currently being tested and will undoubtedly improve the clinical efficacy of these procedures, particularly towards more personalized treatments such as individual rTMS targets and intensities. There are also new techniques for deep brain stimulation based on focused ultrasound that could provide much insight into the treatment of AVH in schizophrenia.

CONCLUSION

This review suggests that add-on brain stimulation treatments could play a key role among the therapeutic strategies for auditory hallucinations reduction in schizophrenia.

Electroconvulsive Therapy in Depression: Current Practice and Future Direction

The current practice of electroconvulsive therapy (ECT) has evolved over several decades with the implementation of safer equipment and advancement of techniques. In addition, modifications in the delivery of ECT, such as the utilization of brief and ultrabrief pulse widths and individualization of treatment parameters, have improved the safety of ECT without sacrificing efficacy. This article aims to provide psychiatrists with a balanced, in-depth look into the recent advances in ECT technique as well as the evidence of ECT for managing depression in special populations and patients with comorbid medical problems.

Electroconvulsive therapy (ECT) in schizophrenia: a review of recent literature

PURPOSE OF REVIEW

ECT remains an important, yet underutilized, treatment for schizophrenia. Recent research shows that medication-resistant patients with schizophrenia, including those resistant to clozapine, respond well to ECT augmentation. The purpose of this article is to review recent studies of the use of ECT in the treatment of schizophrenia.

RECENT FINDINGS

We performed an electronic database search for articles on ECT and schizophrenia, published in 2017. The main themes of these articles are: epidemiological data on ECT use from various countries; retrospective studies, prospective studies and meta-analyses focusing on efficacy and cognitive side-effects of ECT in schizophrenia; ECT technical parameters and potential biomarkers.

SUMMARY

There is growing evidence to support the use of ECT for augmentation of antipsychotic response in the treatment of schizophrenia. Cognitive side-effects are generally mild and transient. In fact, many studies show improvement in cognition, possibly related to the improvement in symptoms. There is wide variation among countries in the use of ECT for the treatment of schizophrenia. There are also variations in the choice of ECT electrode placement, parameters and schedules. These technical differences are likely minor and should not interfere with the treatment being offered to patients. Further, long-term studies are needed to optimize ECT treatment parameters, to examine the effect of maintenance ECT and to investigate neuroimaging/biomarkers to understand the mechanism of action and identify potential response predictors to ECT.