Prior Episodes and ECT Response: New Data From Singapore

The impact of the number of previous illness episodes on early response to electroconvulsive therapy (ECT) in psychosis, mania, depression, psychotic depression, and catatonia: A naturalistic transdiagnostic analysis.

Birong Chen, Tan XW, Tor PC.Psychiatry Res. 2023 Oct 30;330:115580. doi: 10.1016/j.psychres.2023.115580. Online ahead of print.PMID: 37926055

The abstract is copied below:

Electroconvulsive Therapy (ECT) is an effective treatment for mood and psychotic disorders but there is growing evidence of treatment resistant to ECT. Our study aimed to investigate the relationship between the number of previous illness episodes and the symptomatic improvement after acute ECT treatment. We conducted a retrospective naturalistic cohort analysis of patients' ECT registry data from March 2017 to February 2023. We categorized the number of previous illness episodes into "0-3″ and ">3 episodes", paired T-tests were used to compare the changes in scores of clinical assessments, generalized linear models were used to analyze the association between the number of previous illness episodes and change in symptomatic scores. A total of 1137 patients were included for analysis. There was a significant global improvement in psychiatric symptoms (CGI) after 6 ECT treatments across five indications. We observed that compared to patients with less previous illness episodes, patients with more than 3 previous illness episodes had 30% lower chance of response to acute ECT treatment. Thus, our study suggests that use ECT earlier in the course of illness is associated with greater response and support offering ECT earlier in the disease course.

Keywords: Bipolar disorder; Clinical global impression -improvement; Clinical global impression -severity; Depression; Electroconvulsive therapy; Number of previous illness episodes; Schizophrenia.

The article is here.

And from the text:

This is an interesting and complex analysis of a large clinical ECT dataset from Singapore. The main take-home message is simple and clear, that ECT should be prescribed earlier in the course of illness, in order to get better results. The nuances of the subgroup findings are a bit more...well, nuanced. Keep in mind that half the patients were diagnosed with schizophrenia; the concept of episodicity ("prior episodes") is a bit more stretched for psychosis than for recurrent mood disorders.

I hope blog readers will read this paper carefully and comment.

Kudos to Drs. Tor and colleagues for this important contribution to the ECT literature.