ABSTRACT
BACKGROUND: Electroconvulsive therapy (ECT) is a highly effective treatment for depression but how it achieves its clinical effects remains unclear. METHODS: We set out to study the brain's response to ECT from a large-scale brain-network perspective. Using a voxelwise analysis, we looked at resting-state functional connectivity before and after a course of ECT at the whole-brain and the between- and within-network levels in 17 patients with a depressive episode. Using a group-independent component analysis approach, we focused on four networks known to be affected in depression: the salience network (SN), the default mode network (DMN), the cognitive executive network (CEN), and a subcortical network (SCN). Our clinical measures included mood, cognition, and psychomotor symptoms. RESULTS: We found ECT to have increased the connectivity of the left CEN with the left angular gyrus and left middle frontal gyrus as well as its within-network connectivity. Both the right CEN and the SCN showed increased connectivity with the precuneus and the anterior DMN with the left amygdala. Finally, improvement of psychomotor retardation was positively correlated with an increase of within-posterior DMN connectivity. LIMITATIONS: The limitations of our study include its small sample size and the lack of a control dataset to confirm our findings. CONCLUSION: Our voxelwise data demonstrate that ECT induces a significant increase of connectivity across the whole brain and at the within-network level. Furthermore, we provide the first evidence on the association between an increase of within-posterior DMN connectivity and an improvement of psychomotor retardation, a core symptom of depression.
Subject(s)
Electroconvulsive Therapy , Brain/diagnostic imaging , Brain Mapping , Cognition , Depression , Humans , Magnetic Resonance ImagingABSTRACT
INTRODUCTION: The neurobiological mechanisms underlying the acute cognitive effects of electroconvulsive therapy (ECT) remain poorly understood. Prior research has shown that proinflammatory cytokines such as IL-6, TNF-α, IL1-ß, and IL-10 may interfere with cognitive functioning. Interestingly, immunomodulation is one of the proposed modes of action of ECT. This study investigates whether changes of peripheral levels of IL-6, TNF-α, IL1-ß, and IL-10 are related to changes in cognitive functioning following ECT. METHODS: In the week before and 1 week after an acute course of ECT, 62 patients suffering from depression underwent a neuropsychological evaluation to assess their processing speed using the Symbol Digit Substitution Test (SDST), verbal episodic memory using the Hopkins Verbal Learning Test-Revised (HVLT-R), and their retrospective autobiographic memory using the Autobiographical Memory Interview (AMI) with the peripheral inflammatory markers being measured at the same 2 time points. RESULTS: Patients improved drastically following ECT, while their main performance on both the HVLT-R and AMI declined and their SDST scores remained stable. The levels of IL-6 and IL1-ß had both decreased, where the decrease in IL-6 was related to the decrease in HVLT-R scores. Higher baseline IL-10 levels were associated with a more limited decrease of the HVLT-R scores. CONCLUSION: Our findings tentatively suggest that the effects of ECT on verbal episodic memory may be related to the treatment's immunomodulatory properties, most notably due to decreased IL-6 levels. Moreover, baseline IL-10 appears to be a potential biomarker to predict the effects of ECT on verbal episodic memory. Whilst compelling, the results of this study should be interpreted with caution as, due to its exploratory nature, no correction for multiple comparisons was made. Further, a replication in larger cohorts is warranted.
Subject(s)
Electroconvulsive Therapy , Memory, Episodic , Biomarkers , Cognition , Depression/therapy , Humans , Neuropsychological Tests , Retrospective Studies , Treatment OutcomeABSTRACT
Psychotic depression is a frequent, severe psychiatric condition in older depressive inpatients aged 60 years and older. Older adults with a psychotic depression exhibit specific symptoms that are different from those in younger adults with psychotic depression. Moreover, the symptoms are also different from those in older adults with a major depression without psychotic features. The recommended treatment consists of a tricyclic antidepressant, with or without addition of an antipsychotic, or electroconvulsive therapy. These treatments may however produce significant side effects that require intensive monitoring. In this article we present an overview of clinical topics regarding the diagnosis and treatment of older people with a psychotic depression.
