A symptom-based approach in predicting ECT outcome in depressed patients employing MADRS single items

Electroconvulsive therapy in the maintenance phase of psychotic unipolar depression

OBJECTIVE

To determine whether the rates of readmissions and suicide vary in psychotic unipolar depression based on whether patients receive maintenance electroconvulsive therapy (M-ECT) following the initial series of ECT, and to examine if there is an age-dependent association.

METHODS

We used Swedish national registries to identify hospitalized patients with psychotic unipolar depression, treated 2008-2019 who received ECT during their hospital stay. The patients who received subsequent M-ECT within 14 days after discharge were compared with those who did not. The primary composite outcome was time to readmission due to a psychiatric disorder, suicide attempt, or suicide within 2 years from discharge. Data were analyzed using Cox regression adjusted for previous psychiatric admissions, age, sex, comorbidity, and pharmacological treatment. We also conducted a within-individual analysis using the sign-test, with patients having ≥1 hospital episode followed by M-ECT and ≥1 hospital episode without M-ECT.

RESULTS

A total of 1873 patients were included, of which 130 received M-ECT. There was no statistically significant group difference regarding the primary outcome in the whole sample. However, when stratified by age, there was a significant difference in favor of M-ECT for patients >65 years (adjusted hazard ratio 0.55, 95% confidence interval 0.35-0.87). The within-individual analysis, including 46 patients, significantly favored M-ECT.

CONCLUSION

M-ECT was not associated with a differential risk of the composite of readmission and suicide in psychotic depression. Among patients >65 years, M-ECT was significantly associated with a decreased risk of the outcome. The possibility of residual confounding cannot be excluded.

Functional connectivity changes between amygdala and prefrontal cortex after ECT are associated with improvement in distinct depressive symptoms

Electroconvulsive therapy (ECT) is one of the most effective treatments for treatment-resistant depression. However, the underlying mechanisms of action are not yet fully understood. The investigation of depression-specific networks using resting-state fMRI and the relation to differential symptom improvement might be an innovative approach providing new insights into the underlying processes. In this naturalistic study, we investigated the relationship between changes in resting-state functional connectivity (rsFC) and symptom improvement after ECT in 21 patients with treatment-resistant depression. We investigated rsFC before and after ECT and focused our analyses on FC changes directly related to symptom reduction and on FC at baseline to identify neural targets that might predict individual clinical responses to ECT. Additional analyses were performed to identify the direct relationship between rsFC change and symptom dimensions such as sadness, negative thoughts, detachment, and neurovegetative symptoms. An increase in rsFC between the left amygdala and left dorsolateral prefrontal cortex (DLPFC) after ECT was related to overall symptom reduction (Bonferroni-corrected p = 0.033) as well as to a reduction in specific symptoms such as sadness (r = 0.524, uncorrected p = 0.014), negative thoughts (r = 0.700, Bonferroni-corrected p = 0.002) and detachment (r = 0.663, p = 0.004), but not in neurovegetative symptoms. Furthermore, high baseline rsFC between the left amygdala and the right frontal pole (FP) predicted treatment outcome (uncorrected p = 0.039). We conclude that changes in FC in regions of the limbic-prefrontal network are associated with symptom improvement, particularly in affective and cognitive dimensions. Frontal-limbic connectivity has the potential to predict symptom improvement after ECT. Further research combining functional imaging biomarkers and a symptom-based approach might be promising.

Transcutaneous Electrical Cranial-Auricular Acupoint Stimulation Modulating the Brain Functional Connectivity of Mild-to-Moderate Major Depressive Disorder: An fMRI Study Based on Independent Component Analysis

Evidence has shown the roles of taVNS and TECS in improving depression but few studies have explored their synergistic effects on MDD. Therefore, the treatment responsivity and neurological effects of TECAS were investigated and compared to escitalopram, a commonly used medication for depression. Fifty patients with mild-to-moderate MDD (29 in the TECAS group and 21 in another) and 49 demographically matched healthy controls were recruited. After an eight-week treatment, the outcomes of TECAS and escitalopram were evaluated by the effective rate and reduction rate based on the Montgomery-Asberg Depression Rating Scale, Hamilton Depression Rating Scale, and Hamilton Anxiety Rating Scale. Altered brain networks were analyzed between pre- and post-treatment using independent component analysis. There was no significant difference in clinical scales between TECAS and escitalopram but these were significantly decreased after each treatment. Both treatments modulated connectivity of the default mode network (DMN), dorsal attention network (DAN), right frontoparietal network (RFPN), and primary visual network (PVN), and the decreased PVN-RFPN connectivity might be the common brain mechanism. However, there was increased DMN-RFPN and DMN-DAN connectivity after TECAS, while it decreased in escitalopram. In conclusion, TECAS could relieve symptoms of depression similarly to escitalopram but induces different changes in brain networks.

Investigation of Neurofunctional Changes Over the Course of Electroconvulsive Therapy

BACKGROUND

Electroconvulsive therapy (ECT) is an effective treatment for patients suffering from depression. Yet the exact neurobiological mechanisms underlying the efficacy of ECT and indicators of who might respond best to it remain to be elucidated. Identifying neural markers that can inform about an individual's response to ECT would enable more optimal treatment strategies and increase clinical efficacy.

METHODS

Twenty-one acutely depressed inpatients completed an emotional working memory task during functional magnetic resonance imaging before and after receiving treatment with ECT. Neural activity was assessed in 5 key regions associated with the pathophysiology of depression: bilateral dorsolateral prefrontal cortex and pregenual, subgenual, and dorsal anterior cingulate cortex. Associations between brain activation and clinical improvement, as reflected by Montgomery-Åsberg Depression Rating Scale scores, were computed using linear regression models, t tests, and Pearson correlational analyses.

RESULTS

Significant neurobiological prognostic markers or changes in neural activity from pre- to post ECT did not emerge.

CONCLUSIONS

We could not confirm normalization effects and did not find significant neural markers related to treatment response. These results demonstrate that the search for reliable and clinically useful biomarkers for ECT treatment remains in its initial stages and still faces challenges.

Serum Mature BDNF Level Is Associated with Remission Following ECT in Treatment-Resistant Depression

The search for a biological marker predicting the future failure or success of electroconvulsive therapy (ECT) remains highly challenging for patients with treatment-resistant depression. Evidence suggests that Brain-Derived Neurotrophic Factor (BDNF), a protein known to be involved in brain plasticity mechanisms, can play a key role in both the clinical efficacy of ECT and the pathophysiology of depressive disorders. We hypothesized that mature BDNF (mBDNF), an isoform of BDNF involved in the neural plasticity and survival of neural networks, might be a good candidate for predicting the efficacy of ECT. Total BDNF (tBDNF) and mBDNF levels were measured in 23 patients with severe treatment-resistant depression before (baseline) they received a course of ECT. More precisely, tBDNF and mBDNF measured before ECT were compared between patients who achieved the criteria of remission after the ECT course (remitters, n = 7) and those who did not (non-remitters, n = 16). We found that at baseline, future remitters displayed significantly higher mBDNF levels than future non-remitters (p = 0.04). No differences were observed regarding tBDNF levels at baseline. The multiple logistic regression model controlled for age and sex revealed that having a higher baseline mBDNF level was significantly associated with future remission after ECT sessions (odd ratio = 1.38; 95% confidence interval = 1.07–2.02, p = 0.04). Despite the limitations of the study, current findings provide additional elements regarding the major role of BDNF and especially the mBDNF isoform in the clinical response to ECT in major depression.