Baseline EEG as a Response Predictor in ECT: Systematic Review From France

Out on PubMed, from investigators in France, is this review:

Using EEG to Predict Clinical Response to Electroconvulsive Therapy in Patients With Major Depression: A Comprehensive Review.

Simon L, Blay M, Galvao F, Brunelin J.Front Psychiatry. 2021 Jun 24;12:643710. doi: 10.3389/fpsyt.2021.643710. eCollection 2021.PMID: 34248695 

The abstract is copied below:

Introduction: An important approach to improve the therapeutic effect of electroconvulsive therapy (ECT) may be to early characterize patients who are more likely to respond. Our objective was to explore whether baseline electroencephalography (EEG) settings before the beginning of ECT treatment can predict future clinical response to ECT in patients with depressive disorder. Methods: We conducted a systematic search in the MEDLINE, EMBASE, PsycINFO, Web of Science, and Cochrane Central Register of Controlled Trials (CENTRAL) databases to identify studies using EEG in adults with depressive disorder treated by ECT. To investigate the predictive value of baseline EEG on clinical outcomes of ECT, we extracted from the retrieved studies and qualitatively described the association between the baseline EEG markers characteristics and the rates of future responders and/or remitters to ECT. Results: The primary search yielded 2,531 potentially relevant citations, and 12 articles were selected according to inclusion criteria. Most of the studies were prospective studies with small sample size. Sociodemographic and clinical characteristics of patients, ECT settings, EEG settings, and outcomes were heterogeneous. Event-related potential (ERP) paradigms were used in three studies, polysomnography was used in three studies, and the six other studies used EEG to measure cerebral connectivity and activity. Conclusions: P300 amplitude, coherence, and connectivity measures were correlated with remission in patients with depression treated by ECT. Sleep EEG recordings seemed not to be correlated with remission after ECT. Further prospective studies with large sample size are needed to determine optimal EEG parameters associated with clinical response to ECT in depressive disorder. Systematic Review Registration: PROSPERO CRD42020181978.

Keywords: ECT; EEG; biomarker; depression; major depression; prediction.

This is a disappointingly uninformative systematic review. It starts from a very narrow perspective: including only studies using baseline EEG (or related measures, P300 amplitude or connectivity) to predict ECT response. Not surprisingly, there are really no solid, worthwhile conclusions. This is one of those areas that if there had already been a very promising finding in the literature, we would have known about it. But perhaps the P300 findings or connectivity studies will be replicated in the future...

Seems to me, this is just jumping on the bandwagon of systematic reviews and meta-analyses, yet another "least publishable unit."

IMO, no reason to read this in full.

The pd is here.