Prognostic Factors for Postictal Agitation After Electroconvulsive Therapy in Older Adults With Depression

Postictal agitation (PIA) is an impactful confusional state occasionally occurring after electroconvulsive therapy (ECT). PIA creates dangerous situations for caregivers and patients, prolongs lead times, and sometimes leads to the premature discontinuation of ECT. Despite the impact PIA can have on patients and caregivers, little is known about its incidence and the factors associated with its occurrence. This study aims to investigate putative prognostic factors for PIA.

We utilized data from the "Rivastigmine for ECT-induced Cognitive Adverse effects in Late-Life depression" (RECALL) prospective cohort study; a study on older adults (≥ 55 years) with a major depressive episode receiving ECT. We investigated several putative prognostic factors based on previous research, biological plausibility, and availability. PIA was defined by either a Richmond Agitation-Sedation score ≥ 2 or the administration of emergency medication specifically for PIA. Mixed-effects logistic regression was used to analyze univariate and adjusted odds ratios for the prognostic factors.

We included 142 patients who received 1838 ECT sessions. The incidence of PIA was 34.5% at the patient-level and 9.2% at the session-level. A small subset of older adults (19.7%) accounted for 87.5% of all PIA occurrences. We found that male sex, flumazenil use, and a longer seizure duration were associated with higher odds of developing PIA. Multi-seizure sessions and a higher level of education were associated with lower occurrence of PIA.

This study identified sex, flumazenil use, seizure duration, the amount of seizures during a session, and education level as prognostic factors for PIA. The pronounced clustering of PIA events within a small subset of patients suggests meaningful interindividual vulnerability, but should be replicated in future studies. If confirmed, these findings could provide actionable insights for preventive treatment strategies. In particular, the use of flumazenil should be critically reconsidered in persons experiencing PIA.

EudraCT 2014-003385-24.