RANDOMIZED CLINICAL-TRIAL OF MELATONIN AFTER NIGHT-SHIFT WORK - EFFICACY AND NEUROPSYCHOLOGIC EFFECTS

Objective: Melatonin has received considerable publicity for its sleep -promoting properties; however, there is little scientific evidence of its efficacy. The objective of this study is to determine whether the re are measurable beneficial effects from exogenous melatonin in emerg ency physicians after intermittent night-shift duty. Methods: This ran domized, placebo-controlled, double-blind, crossover trial was conduct ed in the emergency department of an urban tertiary care hospital. Fif teen emergency physicians were given melatonin 5 mg or placebo for 3 c onsecutive nights after night-shift duty with crossover to the opposit e agent after a subsequent block of night shifts. The primary outcome measure was the global assessment of recovery measured by a visual ana log scale. Secondary outcome measures included sleep quality, duration , and tiredness. In addition, the Profile of Mood States questionnaire and neuropsychologic testing were performed. Results: There was no di fference between melatonin and placebo in the global assessment of rec overy (60.4+/-16.9 and 58.9+/-14.5, respectively; P=.29). There were n o differences in sleep quality, duration or tiredness scores, sleep la tency, hours of sleep obtained per night, and night or early awakening at any measurement point. Profile of Mood States and neuropsychologic test performances were similar. Conclusion: We found no beneficial ef fect of melatonin on sleep quality, tiredness, or cognitive function i n emergency physicians after night-shift duty. Our results suggest tha t exogenous melatonin is of limited value in recovery from night-shift work in emergency physicians.