"En Bloc" ECT in Denmark: New Register Study in Nordic Journal of Psychiatry

Out on PubMed, from investigators in Denmark and the USA is this study:

The use of electroconvulsive therapy (ECT) en bloc in Denmark: a nationwide register-based study.

Pedersen MI, Salagre E, Kellner CH, Rohde C, Østergaard SD.Nord J Psychiatry. 2022 Nov 7:1-7. doi: 10.1080/08039488.2022.2142279. Online ahead of print.PMID: 36344233

The abstract is copied below:

Objective: Electroconvulsive therapy (ECT) en bloc is defined as ECT administered on 2-3 consecutive days. In Denmark, ECT en bloc is recommended for severe conditions such as catatonia, treatment-resistant mania/psychosis, or imminent risk of suicide. To our knowledge, there are no recent reports on the use of ECT en bloc in clinical practice. Here, we provide such a report.

Methods: We characterized the use of ECT en bloc in the period from 2006-2019 based on data from Danish national registers. Furthermore, we compared mortality rates between patients receiving ECT en bloc and patients receiving standard regimen ECT (not en bloc).

Results: We identified 2173 patients who received a total of 2734 ECT en bloc treatment courses in Denmark in the period from 2006 to 2019 (6% of the total number of ECT treatment courses). The use of ECT en bloc was stable over the study period (range: 138-196 patients per year). The most common treatment indications were unipolar depression (41%), psychotic disorder (23%), and bipolar disorder (20%). The vast majority (90%) received ECT en bloc voluntarily. The 1-year mortality rate ratio for ECT en bloc compared to standard regimen ECT was 1.42 (95%CI: 1.03-1.95).

Conclusion: The use of ECT en bloc in Denmark is stable both in terms of the number of patients treated and treatment indications. In keeping with ECT en bloc being used for severe conditions, those receiving this treatment have a higher mortality rate compared to those receiving standard ECT, warranting careful monitoring during follow-up.

Keywords: Electroconvulsive therapy; mental disorders; mortality; registries; survival.

The article is here.

And from the text:

I am pleased to be an author on this register-based study from Denmark, and thank Dr. Østergaard for the opportunity to collaborate. Yet again, Scandinavian data allow us to explore a technical aspect of ECT treatment. Giving ECT on consecutive days for urgently ill patients has been a feature of clinical practice for a long time, but, as we note, the literature is sparse. Use of daily ECT in catatonia and NMS is sometimes reported in the literature; we note that one of the shortcomings of these register-based data is the lack of detail about the patients' clinical situation, beyond their listed main psychiatric/medical diagnoses.

"En bloc" ECT is technique for providing the most "powerful" ECT for the most urgently ill patients; it is generally also accepted that bilateral ECT and higher stimulus dose ECT are more powerful forms of ECT.  Rasmussen et al. (2016) suggested use of daily RUL ECT to speed response while maintaining high tolerability in more typical ECT patients. Perhaps one day we will have tested algorithms for selecting the most appropriate form/"strength" of ECT for a particular patient's clinical situation.