Melatonin intervention to prevent delirium in hospitalized patients: A meta-analysis

Effects of melatonin on the prevention of delirium in hospitalized older patients: systematic review and meta-analysis

OBJECTIVES

Melatonin has been demonstrated to exert a preventive effect on delirium. This meta-analysis sought to investigate the preventive effects of melatonin and melatonin receptor agonists (ramelteon) on delirium in hospitalized elderly patients.

METHODS

This systematic review and meta-analysis delineates the risk of delirium events in older hospitalized patients with melatonin/ramelteon compared with placebo, incorporating randomized controlled trials published up to 8 July 2024. The databases searched were PubMed, Embase and the Cochrane Library. The primary outcome measures were the incidence of delirium, while the secondary outcome measures were the length of hospital stay and mortality. The results are presented as odds ratios (OR) or mean differences (MD) with a 95% confidence interval. The review of publications was conducted in accordance with the guidelines set forth in the Cochrane Handbook and the Preferred Reporting Project for Systematic Review and Meta-Analysis (PRISMA). This study has been registered with INPLASY (number INPLASY202470044).

RESULTS

A total of 2086 patients were included in 13 randomized controlled trials. The primary outcome of this meta-analysis demonstrated a statistically difference in the incidence of delirium between the melatonin and placebo groups in hospitalized elderly patients (OR = 0.59, 95% CI: 0.40-0.87, P < 0.01, I2 = 60%), particularly in those who had undergone surgery (OR = 0.60, 95%CI: 0.40-0.89, P = 0.01, I2 = 53%). No statistically differences were observed in terms of length of stay (MD=-0.07, 95%CI:-1.09-0.94, P = 0.89, I2 = 72%) and mortality (OR = 0.79, 95%CI:0.58-1.06, P = 0.12, I2 = 0%).

CONCLUSIONS

Melatonin has been demonstrated to exert a protective effect on delirium in elderly patients who are hospitalized, particularly in the context of perioperative care.

Delirium and sleep disturbances-A narrative review

BACKGROUND

Delirium is considered a severe complication. It increases morbidity and mortality and represents a major financial burden for healthcare systems. Thus, prevention becomes a focal point of research. Sleep disturbances have been linked to the occurrence of delirium. Consequently, several interventions that target a possible connection have been studied in recent years.

OBJECTIVE

This narrative literature review explores the published data for an association between delirium and different types of sleep disturbances, the pathophysiological interactions and prevention methods.

MATERIAL AND METHODS

A literature search was carried out utilizing PubMed, the Cochrane Library, Livivo and Google Scholar.

RESULTS

Although an association between several types of sleep disturbances and delirium has been shown, no causality has been proven so far. Nevertheless, several pharmacological and nonpharmacological interventions for delirium prevention have been attempted; however, the level of evidence is insufficient at this point.

CONCLUSION

Further research is required to prove causality between sleep disturbances and delirium. Nonpharmacological interventions should be used in construction and maintenance of intensive care units and hospitals. Pharmacological interventions could be effective for prevention but further research is needed. Screening patients at risk of delirium for sleep disturbances and antihistaminergic/anticholinergic medication seems beneficial.

Melatonin’s actions are not limited to sleep

Melatonin is widely available as a supplement, usually for sleep disorders. The consumption of melatonin supplements has increased considerably in recent years. An overlooked aspect of melatonin’s administration is the resulting increase in prolactin secretion, via its action on hypothalamic dopaminergic neurons. We believe that since the effect of melatonin on prolactin is tangible, the laboratory finding of hyperprolactinemia could be encountered more often, given the increase in melatonin’s use. This is an issue that merits further study.