Significant decrease in delirium referrals after changing hypnotic from benzodiazepine to suvorexant

Orexin receptor antagonists versus antipsychotics for the management of delirium in intensive care unit patients with cardiovascular disease: A retrospective observational study

OBJECTIVE

Although antipsychotics are often used in the pharmacological treatment of delirium, recent reports suggest the efficacy of orexin receptor antagonists. This study investigated whether orexin receptor antagonists could be a possible treatment option for delirium.

METHOD

A nonblinded nonrandomized routine clinical treatment was performed. Patients treated in intensive care units (ICU) for cardiovascular disease and receiving psychiatric intervention were studied retrospectively. The scores from the Intensive Care Delirium Screening Checklist (ICDSC) were compared between patients treated with orexin receptor antagonists and those treated with antipsychotics.

RESULTS

The mean (standard deviation) ICDSC scores were 4.5 (1.8) at day -1 and 2.6 (2.6) at day 7 for orexin receptor antagonist group (n = 25) and 4.6 (2.4) at day -1 and 4.1 (2.2) at day 7 for antipsychotic group (n = 28). The orexin receptor antagonist group showed significantly lower ICDSC scores than the antipsychotic group (p = 0.021).

CONCLUSION

While precise efficacy cannot be determined from our retrospective, observational, and uncontrolled pilot study, this analysis encourages a future double-blind randomized placebo-controlled trial of orexin-antagonists for delirium treatment.

Reducing the effect of immortal time bias affects the analysis of prevention of delirium by suvorexant in critically ill patients: A retrospective cohort study

BACKGROUND

Studies assessing the effect of suvorexant on delirium prevention included patients treated before development of delirium, which can introduce immortal time bias. The objective of the present study was to evaluate the effect of suvorexant on delirium, comparing patients treated before the onset of delirium with patients treated within 72h of admission using the same dataset.

METHODS

Data from adult patients admitted to the ICU from August 2018 to July 2021 were retrospectively analyzed. In "any time before" analysis, the incidence of delirium was compared for patients who received suvorexant at any time during their ICU stay (suvorexant) (unless delirium developed before treatment) with patients who either did not receive suvorexant or received suvorexant after development of delirium (control). This design was used in previously published studies. In "within 72h" analysis, the incidence of delirium was compared for patients who received suvorexant within 72 hours of admission (suvorexant) and patients who did not receive suvorexant or received it more than 72 hours after admission (control). Patients who developed delirium during the initial 72 hours were excluded from "within 72h" analysis (N = 799).

RESULTS

"Within 72h" analysis included 1,255 patients, and "any time before" analysis included 2,054 patients (of 6599 admissions). The unadjusted hazard ratio of "any time before" analysis was 0.16 and the 95% confidence interval was 0.13-0.21 (p<0.01). The adjusted hazard ratio was 0.21, and the 95% confidence interval was 0.16-0.27 (p<0.01). "Within 72h" analysis had an unadjusted hazard ratio of 0.54 and the 95% confidence interval was 0.36-0.82 (p<0.01). However, this association lost statistical significance after adjustment for potential confounders (adjusted hazard ratio 1.02, 95% confidence interval 0.65-1.59, p = 0.93).

CONCLUSION

Reducing the effect of immortal time bias led to a significantly reduced effect of suvorexant for the prevention of delirium.

Suvorexant with or without ramelteon to prevent delirium: a systematic review and meta-analysis

Delirium is a common and serious neurobehavioral syndrome, associated with prolonged hospital stays, and increased morbidity and mortality. As it remains unclear whether suvorexant with or without ramelteon prevents delirium in elderly hospitalized patients, we conducted a systematic review and meta-analysis to evaluate, searching the PubMed, Cochrane Library, Web of Science, EMBASE, and EBSCOhost databases for all randomized controlled trials (RCTs), case-control studies, and cohort studies that investigated the effects of suvorexant with or without ramelteon on delirium in adult hospitalized patients. The primary outcome was the incidence of delirium. Two randomized controlled trials, 7 cohort studies and 2 case-control studies involving 2594 patients were included in this meta-analysis. The results showed that both suvorexant alone (odds ratio (OR) = 0.30, 95% confidence interval (CI): 0.14-0.65, P = 0.002) and suvorexant with ramelteon (OR = 0.39, 95% CI 0.23-0.65, P = 0.0003) reduced the incidence of delirium in adult hospitalized patients. Six studies involved the use of benzodiazepines; subgroup analysis performed separately in the suvorexant alone and suvorexant with ramelteon groups indicated that when benzodiazepine was administered, suvorexant with ramelteon was effective at reducing the incidence of delirium (OR = 0.53, 95% CI 0.37-0.74, P = 0.0002), but no significant difference was observed for suvorexant alone (OR = 0.40, 95% CI 0.11-1.53, P = 0.18). The current literature thus supports the effectiveness of suvorexant with or without ramelteon for delirium prevention, although suvorexant alone failed to significantly reduce the incidence of delirium when benzodiazepine was administered. The present study was limited by the significant heterogeneity among the included studies, and caution should be exercised when interpreting the results. This study was registered in the PROSPERO database (CRD4202017964).