ECT/Clozapine For Schizophrenia/Schizoaffective Disorder: Retrospective Data From Canada

 Out on PubMed, from Canadian researchers, is this study:

Impact of medications, mood state, and electrode placement on ECT outcomes in treatment-refractory psychosis.

Ainsworth NJ, Avina-Galindo AM, White RF, Zhan D, Gregory EC, Honer WG, Vila-Rodriguez F.Brain Stimul. 2022 Aug 24;15(5):1184-1191. doi: 10.1016/j.brs.2022.08.012. Online ahead of print.PMID: 36028155

The abstract is copied below:

Background: Treatment-refractory psychosis (TRP) is a significant clinical challenge. While clozapine is frequently effective, alternate or augmentation strategies are often necessary. Evidence supports effectiveness of electroconvulsive therapy (ECT), but questions remain about optimal treatment parameters and impacts of concomitant pharmacotherapy.

Objective: /Hypothesis: To analyze the impact of clozapine, anticonvulsant medication, mood state, and ECT electrode placement on outcomes in TRP. We hypothesized that ECT would lead to greater reduction in positive symptoms, particularly in patients receiving clozapine.

Methods: Retrospective study in a tertiary TRP program. The Positive and Negative Syndrome Scale (PANSS) was used for clinical outcomes, with positive subscore as primary outcome. Clinical and ECT data were analyzed using a linear modelling approach, controlling for relevant covariates.

Results: A total of 309 patients were included. ECT plus clozapine associated with greater improvement in positive, general, and total symptoms than ECT alone. ECT associated with greater improvement in negative symptoms in depressed patients. Bifrontal placement was mostly equivalent to bitemporal, with greater reduction of positive symptoms in patients receiving clozapine, and associated with lower electrical dose in patients on anticonvulsants. Clozapine increased seizure duration, while anticonvulsants decreased it. Anticonvulsant use in ECT patients associated with equivalent to slightly improved symptom reduction.

Conclusions: ECT's benefit in TRP may be greatest in patients receiving clozapine. ECT can improve negative symptoms in depressed TRP patients. Bifrontal placement is effective in TRP. Clozapine and anticonvulsants have opposite effects on seizure duration, but anticonvulsants may not adversely affect clinical outcomes of ECT for TRP.

Keywords: Anticonvulsant; Clozapine; Electroconvulsive therapy; Schizophrenia; Treatment-refractory psychosis.

The article is here.

And from the text:

This is a fairly large retrospective study showing the benefits of the ECT-clozapine combination in patients with schizophrenia or schizoaffective disorder. I would not put too much stock in the the sub-findings related to electrode placement, seizure threshold or other concomitant medications. The presentation of the data is somewhat tedious, but that may be unavoidable....

Students/scholars of the ECT in schizophrenia literature will want to finely parse these data, I am sure, ~25 minutes.