Prophylactic Use of Ramelteon for Delirium in Hospitalized Patients: A Systematic Review and Meta-Analyses

Background: Small prospective studies, case reports, as well as some randomized placebo-controlled trials and previous meta-analyses have shown that ramelteon, a melatonin agonist, may reduce the risk of developing delirium. Objective: The goal of this systemic review and meta-analyses was to assess the current evidence supporting the use of ramelteon in delirium prevention by including data from larger (>100 subjects) and more recent trials since the most recent meta-analyses were published in 2019. There were no exclusions for trial size, age, ramelteon dose, length of treatment, or hospital setting. Methods: Medline, Embase, PsycINFO, EBM Reviews, Scopus, and Web of Science databases were queried using the search terms delirium (with subterms including prevention and control), ramelteon, Rozerem, or melatonin receptor agonists, for English-language publications until March 16, 2021. Randomized placebo-controlled trials of hospitalized subjects receiving ramelteon for delirium prevention were included. The primary outcome of interest was delirium incidence. Odds ratios of the risk of developing incident delirium and 95% confidence intervals were calculated using a random effects model. Results: A total of 177 articles were identified by the literature search. Five studies (n = 443, 53.7% male) met criteria for inclusion in the final meta-analyses. The meta-analyses of the randomized placebo-controlled trials revealed that ramelteon did not result in a reduction in the risk of incident delirium (n = 443; odds ratio = 0.49; 95% confidence interval = 0.13–1.85). A moderate degree of heterogeneity was noted among the studies (I² = 53%). Conclusions: Current evidence suggests that ramelteon is ineffective as a prophylactic drug in reducing the incidence of delirium in hospitalized patients.