Factors associated with post-electroconvulsive therapy delirium: A retrospective chart review study

Although electroconvulsive therapy (ECT) is generally a safe therapeutic method, unexpected adverse effects, such as post-ECT delirium, may occur. Despite its harmful consequences, there has been little discussion about the predictors of post-ECT delirium. Thus, the current study aimed to clarify the factors associated with post-ECT delirium by reviewing electronic medical records of 268 bitemporal ECT sessions from December 2006 to July 2018 in a university hospital. Demographic and clinical characteristics of sessions involving patients with or without post-ECT delirium were compared. Multiple logistic regression analysis was applied to analyze the correlation between variables and post-ECT delirium. Post-ECT delirium developed in 23 sessions (8.6%). Of all the demographic and clinical variables measured, only etomidate use was significantly different between delirium-positive and delirium-negative groups after Bonferroni correction. The regression model also indicated that etomidate use to be significantly associated with post-ECT delirium. In this study, etomidate was associated with a higher risk of developing post-ECT delirium, an association that appeared unrelated to other possible measured variables. Practitioners should take into account the risk of post-ECT delirium while choosing anesthetics, so as to prevent early discontinuation before sufficient therapeutic gain is achieved.