Evaluation of Suvorexant and Lemborexant for the Prevention of Delirium in Adult Critically Ill Patients at an Advanced Critical Care Center: A Single-Center, Retrospective, Observational Study.

Objective: There is limited evidence for the efficacy of the novel dual orexin receptor antagonists (DORAs) suvorexant and lemborexant in preventing delirium. We examined the efficacy of DORAs in preventing delirium in critically ill patients at an advanced emergency and critical care center. Methods: In this retrospective observational study, patients 18 years of age or older admitted to the emergency center between July 2018 and November 2021 with hospitalization duration of at least 72 h were included. Kaplan-Meier curves were plotted and log rank tests were performed to compare between patients with and without DORA treatment. Cox regression analyses adjusting for factors associated with delirium risk were also performed. Results: Of the 633 enrolled patients, 82 were treated with suvorexant and 41 with lemborexant. Cox regression analysis showed that, without adjustment, the hazard ratios (95% CIs) for the development of delirium were 0.56 (0.36-0.86) for patients treated with suvorexant and 0.26 (0.11-0.62) for those treated with lemborexant. After adjustment for delirium risk factors, the hazard ratios (95% CIs) remained low at 0.34 (0.20-0.58) for suvorexant and 0.21 (0.08-0.52) for lemborexant. Conclusions: Both suvorexant and lemborexant may be effective in preventing delirium in critically ill adult patients in an advanced critical care center.