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51 result(s) for "McClintock, Shawn M."
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Depression and Cognitive Control across the Lifespan: a Systematic Review and Meta-Analysis
Depression has been shown to negatively impact neurocognitive functions, particularly those governed by fronto-subcortical networks, such as executive functions. Converging evidence suggests that depression-related executive dysfunction is greater at older ages, however, this has not been previously confirmed by meta-analysis. We performed a systematic review and meta-analysis, using three-level models, on peer-reviewed studies that examined depression-related differences in cognitive control in healthy community-dwelling individuals of any age. We focused on studies of cognitive control as defined by the National Institute of Mental Health (NIMH) Research Domain Criteria (RDoC) framework, which centers on goal-directed behavior, such as goal selection (updating, representations, maintenance), response selection (inhibition or suppression), and performance monitoring. In 16,806 participants aged 7 to 97 across 76 studies, both clinical depression and subthreshold depressive symptoms were associated with cognitive control deficits (Hedges’ g = -0.31). This relationship was stronger in study samples with an older mean age. Within studies with a mean age of 39 years or higher, which represents the median age in our analyses, the relationship was stronger in clinical compared to subthreshold depression and in individuals taking antidepressant medication. These findings highlight the importance of clinicians screening for cognitive control dysfunction in patients with depression, particularly in later stages of adulthood.
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.
Magnetic seizure therapy (MST) for major depressive disorder
Electroconvulsive therapy (ECT) is effective for major depressive disorder (MDD) but its effects on memory limit its widespread use. Magnetic seizure therapy (MST) is a potential alternative to ECT that may not adversely affect memory. In the current trial, consecutive patients with MDD consented to receive MST applied over the prefrontal cortex according to an open-label protocol. Depressive symptoms and cognition were assessed prior to, during and at the end of treatment. Patients were treated two to three times per week with high-frequency MST (i.e., 100 Hz) (N = 24), medium frequency MST (i.e., 60 or 50 Hz) (N = 26), or low-frequency MST (i.e., 25 Hz MST) (N = 36) using 100% stimulator output. One hundred and forty patients were screened; 86 patients with MDD received a minimum of eight treatments and were deemed to have an adequate course of MST; and 47 completed the trial per protocol, either achieving remission (i.e., 24-item Hamilton Rating Scale for Depression score <10 and a relative reduction of >60% at two consecutive assessments; n = 17) or received a maximum of 24 sessions (n = 30). High-frequency (100 Hz) MST produced the highest remission rate (33.3%). Performance on most cognitive measures remained stable, with the exception of significantly worsened recall consistency of autobiographical information and significantly improved brief visuospatial memory task performance. Under open conditions, MST led to clinically meaningful reduction in depressive symptoms in patients with MDD and produced minimal cognitive impairment. Future studies should compare MST and ECT under double-blind randomized condition.
Links between electroconvulsive therapy responsive and cognitive impairment multimodal brain networks in late-life major depressive disorder
Background Although electroconvulsive therapy (ECT) is an effective treatment for depression, ECT cognitive impairment remains a major concern. The neurobiological underpinnings and mechanisms underlying ECT antidepressant and cognitive impairment effects remain unknown. This investigation aims to identify ECT antidepressant-response and cognitive-impairment multimodal brain networks and assesses whether they are associated with the ECT-induced electric field (E-field) with an optimal pulse amplitude estimation. Methods A single site clinical trial focused on amplitude (600, 700, and 800 mA) included longitudinal multimodal imaging and clinical and cognitive assessments completed before and immediately after the ECT series ( n = 54) for late-life depression. Another two independent validation cohorts ( n = 84, n = 260) were included. Symptom and cognition were used as references to supervise fMRI and sMRI fusion to identify ECT antidepressant-response and cognitive-impairment multimodal brain networks. Correlations between ECT-induced E-field within these two networks and clinical and cognitive outcomes were calculated. An optimal pulse amplitude was estimated based on E-field within antidepressant-response and cognitive-impairment networks. Results Decreased function in the superior orbitofrontal cortex and caudate accompanied with increased volume in medial temporal cortex showed covarying functional and structural alterations in both antidepressant-response and cognitive-impairment networks. Volume increases in the hippocampal complex and thalamus were antidepressant-response specific, and functional decreases in the amygdala and hippocampal complex were cognitive-impairment specific, which were validated in two independent datasets. The E-field within these two networks showed an inverse relationship with HDRS reduction and cognitive impairment. The optimal E-filed range as [92.7–113.9] V/m was estimated to maximize antidepressant outcomes without compromising cognitive safety. Conclusions The large degree of overlap between antidepressant-response and cognitive-impairment networks challenges parameter development focused on precise E-field dosing with new electrode placements. The determination of the optimal individualized ECT amplitude within the antidepressant and cognitive networks may improve the treatment benefit–risk ratio. Trial registration ClinicalTrials.gov Identifier: NCT02999269.
Magnetic seizure therapy is efficacious and well tolerated for treatment-resistant bipolar depression: an open-label clinical trial
Treatment-resistant bipolar depression can be treated effectively using electroconvulsive therapy, but its use is limited because of stigma and cognitive adverse effects. Magnetic seizure therapy is a new convulsive therapy with promising early evidence of antidepressant effects and minimal cognitive adverse effects. However, there are no clinical trials of the efficacy and safety of magnetic seizure therapy for treatment-resistant bipolar depression. Participants with treatment-resistant bipolar depression were treated with magnetic seizure therapy for up to 24 sessions or until remission. Magnetic seizure therapy was applied over the prefrontal cortex at high (100 Hz; n = 8), medium (50 or 60 Hz; n = 9) or low (25 Hz; n = 3) frequency, or over the vertex at high frequency (n = 6). The primary outcome measure was the 24-item Hamilton Rating Scale for Depression. Participants completed a comprehensive battery of neurocognitive tests. Twenty-six participants completed a minimally adequate trial of magnetic seizure therapy (i.e., ≥ 8 sessions), and 20 completed full treatment per protocol. Participants showed a significant reduction in scores on the Hamilton Rating Scale for Depression. Adequate trial completers had a remission rate of 23.1% and a response rate of 38.5%. Per-protocol completers had a remission rate of 30% and a response rate of 50%. Almost all cognitive measures remained stable, except for significantly worsened recall consistency on the autobiographical memory inventory. The open-label study design and modest sample size did not allow for comparisons between stimulation parameters. In treatment-resistant bipolar depression, magnetic seizure therapy produced significant improvements in depression symptoms with minimal effects on cognitive performance. These promising results warrant further investigation with larger randomized clinical trials comparing magnetic seizure therapy to electroconvulsive therapy. NCT01596608; clinicaltrials.gov
Confirmatory Efficacy and Safety Trial of Magnetic Seizure Therapy for Depression (CREST-MST): study protocol for a randomized non-inferiority trial of magnetic seizure therapy versus electroconvulsive therapy
Background Electroconvulsive therapy (ECT) is well-established and effective for treatment-resistant depression (TRD), but in Canada and the USA, less than 1% of patients with TRD receive ECT mainly due to its cognitive adverse effects (i.e. amnesia). Thus, new treatment alternatives for TRD are urgently needed. One such treatment is magnetic seizure therapy (MST). ECT involves applying a train of high-frequency electrical stimuli to induce a seizure, whereas MST involves applying a train of high-frequency magnetic stimuli to induce a seizure. Methods In this manuscript, we introduce our international, two-site, double-blinded, randomized, non-inferiority clinical trial to develop MST as an effective and safe treatment for TRD. This trial will compare the efficacy of MST to right unilateral ultra-brief pulse width electroconvulsive therapy (RUL-UB-ECT) with a combined primary endpoint of remission of depression and superior cognitive adverse effects in 260 patients with TRD. Amelioration of suicidal ideation will be assessed as a secondary endpoint. Inpatients or outpatients, over 18 years of age with a MINI International Neuropsychiatric Interview (MINI) diagnosis of non-psychotic major depressive disorder (MDD) can be enrolled in the study provided that they meet illness severity and full eligibility criteria. Participants are randomized to receive MST or RUL-UB ECT, 2-3 days per week over seven weeks, or a maximum of 21 treatments. The study will involve before-, during-, and after-treatment assessments of depression severity, suicidal ideation, subjective side-effects, and cognitive performance consistent with an intent-to-treat study design approach. Discussion Positive results from this trial could have an immediate and tremendous impact for patients with TRD. If MST demonstrates comparable antidepressant treatment efficacy to ECT, but with greater cognitive safety, it could rapidly be adopted into clinical practice. Indeed, given that the administration of MST is nearly identical to ECT, the majority of ECT facilities in North America could readily adopt MST. Furthermore, the potential for cognitive safety could lead to improved treatment acceptability. Healthcare providers, patients and care partners, and policymakers would therefore demand this form of convulsive therapy. Trial status Enrollment for this study began on June 26, 2018, and is estimated to complete recruitment by July 2024. At the time of submission, we have enrolled and randomized 117 participants. Trial registration ClinicalTrials.gov NCT03191058 , Registered on June 19, 2017. Primary sponsor: Daniel Blumberger (DMB), Principal Investigator Daniel.Blumberger@camh.ca, 416-535-8501 x 33662 Contact for public queries: DMB, Daniel.Blumberger@camh.ca Contact for scientific queries: ZJD, Zdaskalakis@health.ucsd.edu
Cerebro-cerebellar functional neuroplasticity mediates the effect of electric field on electroconvulsive therapy outcomes
Electroconvulsive therapy (ECT) is the most effective treatment for severe depression and works by applying an electric current through the brain. The applied current generates an electric field (E-field) and seizure activity, changing the brain’s functional organization. The E-field, which is determined by electrode placement (right unilateral or bitemporal) and pulse amplitude (600, 700, or 800 milliamperes), is associated with the ECT response. However, the neural mechanisms underlying the relationship between E-field, functional brain changes, and clinical outcomes of ECT are not well understood. Here, we investigated the relationships between whole-brain E-field (Ebrain, the 90th percentile of E-field magnitude in the brain), cerebro-cerebellar functional network connectivity (FNC), and clinical outcomes (cognitive performance and depression severity). A fully automated independent component analysis framework determined the FNC between the cerebro-cerebellar networks. We found a linear relationship between Ebrain and cognitive outcomes. The mediation analysis showed that the cerebellum to middle occipital gyrus (MOG)/posterior cingulate cortex (PCC) FNC mediated the effects of Ebrain on cognitive performance. In addition, there is a mediation effect through the cerebellum to parietal lobule FNC between Ebrain and antidepressant outcomes. The pair-wise t-tests further demonstrated that a larger Ebrain was associated with increased FNC between cerebellum and MOG and decreased FNC between cerebellum and PCC, which were linked with decreased cognitive performance. This study implies that an optimal E-field balancing the antidepressant and cognitive outcomes should be considered in relation to cerebro-cerebellar functional neuroplasticity.
Cognitive flexibility in verbal and nonverbal domains and decision making in anorexia nervosa patients: a pilot study
Background This paper aimed to investigate cognitive rigidity and decision making impairments in patients diagnosed with Anorexia Nervosa Restrictive type (AN-R), assessing also verbal components. Methods Thirty patients with AN-R were compared with thirty age-matched healthy controls (HC). All participants completed a comprehensive neuropsychological battery comprised of the Trail Making Test, Wisconsin Card Sorting Test, Hayling Sentence Completion Task, and the Iowa Gambling Task. The Beck Depression Inventory was administered to evaluate depressive symptomatology. The influence of both illness duration and neuropsychological variables was considered. Body Mass Index (BMI), years of education, and depression severity were considered as covariates in statistical analyses. Results The AN-R group showed poorer performance on all neuropsychological tests. There was a positive correlation between illness duration and the Hayling Sentence Completion Task Net score, and number of completion answers in part B. There was a partial effect of years of education and BMI on neuropsychological test performance. Response inhibition processes and verbal fluency impairment were not associated with BMI and years of education, but were associated with depression severity. Conclusions These data provide evidence that patients with AN-R have cognitive rigidity in both verbal and non-verbal domains. The role of the impairment on verbal domains should be considered in treatment. Further research is warranted to better understand the relationship between illness state and cognitive rigidity and impaired decision-making.
Confirmatory Efficacy and Safety Trial of Magnetic Seizure Therapy for Depression (CREST-MST): protocol for identification of novel biomarkers via neurophysiology
Background Electroconvulsive therapy (ECT) is the most effective treatment for treatment-resistant depression (TRD), especially for acute suicidal ideation, but the associated cognitive adverse effects and negative stigma limit its use. Another seizure therapy under development is magnetic seizure therapy (MST), which could potentially overcome the restrictions associated with ECT with similar efficacy. The neurophysiological targets and mechanisms of seizure therapy, however, remain poorly understood. Methods/design This neurophysiological study protocol is published as a companion to the overall Confirmatory Efficacy and Safety Trial of Magnetic Seizure Therapy for Depression (CREST-MST) protocol that describes our two-site, double-blind, randomized, non-inferiority clinical trial to develop MST as an effective and safe treatment for TRD. Our aim for the neurophysiological component of the study is to evaluate two biomarkers, one to predict remission of suicidal ideation (primary outcome) and the other to predict cognitive impairment (secondary outcome). Suicidal ideation will be assessed through cortical inhibition, which according to our preliminary studies, correlates with remission of suicidal ideation. Cortical inhibition will be measured with simultaneous transcranial magnetic stimulation (TMS) and electroencephalography (EEG), TMS-EEG, which measures TMS-evoked EEG activity. Cognitive adverse effects associated with seizure therapy, on the contrary, will be evaluated via multiscale entropy analysis reflecting the complexity of ongoing resting-state EEG activity. Discussion ECT and MST are known to influence cortical inhibition associated with depression, suicidal ideation severity, and clinical outcome. Therefore, evaluating cortical inhibition and brain temporal dynamics will help understand the pathophysiology of depression and suicidal ideation and define new biological targets that could aid clinicians in diagnosing and selecting treatments. Resting-state EEG complexity was previously associated with the degree of cognitive side effects after a seizure therapy. This neurophysiological metric may help clinicians assess the risk for adverse effects caused by these useful and effective treatments. Trial registration ClinicalTrials.gov NCT03191058 . Registered on June 19, 2017.