DATA SOURCES: MEDLINE, EMBASE and CENTRAL were systematically searched from their inception until December 2018.
REVIEW METHODS: All randomised clinical trials were included.
RESULTS: Sixteen trials (1634 patients) were included in this meta-analysis. Incidence of delirium was not significantly lower in patients who received melatonin, with an odd ratio, OR (95%Cl) of 0.55 (0.24-1.26); ρ = 0.16, certainty of evidence = low, trial sequential analysis = inconclusive. However, patients who randomised to melatonin had a significantly shorter length of stay in intensive care units, with a mean difference, MD (95%CI) of -1.84 days (-2.46, -1.21); ρ melatonin in the prevention of delirium of hospitalised patients. We identified high heterogeneity across all the included trials and low certainty of evidence with potential type II error. Future multi-centre, adequately powered randomised controlled trials are warranted to provide more certainty on the use of melatonin for the prevention of delirium.
PROSPERO: CRD42019123546.