Melatonin prescribing characteristics and delirium outcomes: A health system database-based study

There is heterogeneity in melatonin use for the prevention and treatment of delirium. The optimal dosing and timing of melatonin for these indications are unknown. This study's objectives were to describe melatonin prescribing for hospitalized inpatients in a large healthcare system and to evaluate associations between melatonin prescribing, rates of delirium, and hospital length of stay (LOS) METHODS: A centralized health data repository was queried for all inpatients ages 18 and above who had received at least one dose of melatonin from October 2019 to September 2024. General linear models were used in analyses, with average daily dose of melatonin and average time of melatonin administration serving as exposure variables, and rates of delirium and LOS serving as outcomes. Covariates included demographic variables, antipsychotic/benzodiazepine use, and comorbidities RESULTS: A total of 83,760 patients were included in the cohort. Higher average daily doses of melatonin were associated with lower odds of hospital delirium (OR 0.92, p < 0.001), but melatonin administered from 5 to 8 pm was associated with higher odds of delirium (OR 1.55, p < 0.001). In predicting LOS, there was a decrease of 0.86 days in LOS with every milligram increase in average daily dose of melatonin (95% CI: -0.97 to -0.75, p < 0.001); however, there was an increase of 5.26 days in LOS when melatonin was administered from 5 to 8 pm (95% CI: 4.80 to 5.73, p < 0.001) CONCLUSION: Higher average daily doses of melatonin and melatonin dosed outside the 5-8 pm timeframe were associated with lower odds of delirium and shorter LOS.