Prophylactic melatonin in critically ill patients fails to prevent delirium, Study finds

In a new study conducted by Bradley Wibrow and team it was found that, enteral melatonin started within 48 hours after ICU admission did not diminish the occurrence of delirium. The findings of this study were published in Intensive Care Medicine Journal.

Delirium is prevalent in critically sick patients, is extremely stressful for patients and families, and is linked to increased morbidity and death. The findings of research on the prophylactic use of melatonin in diverse patient groups have been equivocal. The purpose of this study was to see if giving melatonin to critically sick patients reduced the occurrence of delirium.

This research was a randomized, multicenter, placebo-controlled, double-blind experiment that recruited patients from 12 Australian intensive care units from July 2016 to September 2019. Patients over the age of 18 who require ICU admission and have an estimated length of stay (LOS) of more than 72 hours; enrolled within 48 hours after ICU admission. For 14 consecutive nights or until ICU discharge, indistinguishable liquid melatonin (4 mg; n = 419) or placebo (n = 422) was provided enterally at 21:00 h. The primary outcome was the proportion of delirium-free evaluations performed within 14 days of ICU discharge as a measure of delirium prevalence. The Confusion Assessment Method for ICU (CAM-ICU) score was used to measure delirium twice daily. hospital and ICU LOS, sleep quality and quantity, and hospital and 90-day death were all secondary outcomes.

The findings of this study are as follow:

1. A total of 847 patients were randomly assigned to the trial, with 841 of them included in the data analysis.

2. The subjects' baseline characteristics were similar. The average proportion of delirium-free evaluations per patient did not differ significantly between the melatonin and placebo groups.

3. There was no statistically significant difference in any secondary outcomes, including ICU LOS (median: 5 vs 5 days, p = 0.135), hospital LOS (median: 14 vs 12 days, p = 0816), death at any time point, including 90 days (15.5 vs 15.6%, p = 0.948), or sleep quantity or quality.

4. In either group, no major adverse effects were documented.

In conclusion, these data of this specific study do not support the usual use of melatonin in critically sick patients.

Reference:

Wibrow, B., Martinez, F.E., Myers, E. et al. Prophylactic melatonin for delirium in intensive care (Pro-MEDIC): a randomized controlled trial. Intensive Care Med (2022). https://doi.org/10.1007/s00134-022-06638-9