LAUSR

Objective Coronavirus has disrupted the natural order of the world since September 2019 with no specific medication. The beneficial effects of melatonin on sepsis and viral influenza were demonstrated previously, but its effects on covid-19, especially COVID -19 ICU, is unclear. Therefore, our aim was to determine the effects of melatonin in COVID-19 ICU patients. Methods This is a retrospective cohort study in which the records of patients admitted to COVID -19 ICU of (XXX) during March to June 2020 were reviewed. According to inclusion criteria, patients who received 15 mg of melatonin daily were called MRG and the rest were called NMRG. Results Thirty-one patients were included and analyzed, of which twelve patients were in MRG. Demographic and clinical characteristics, and laboratory data were similar between two groups at ICU admission. Melatonin had no significant effect on ICU duration, CRP and ESR, also the trend of changes was in favor of melatonin. Nevertheless, melatonin significantly reduced the NLR (OR = −9.81, p = 0.003), and also declined mortality marginally (p = 0.09). Melatonin was well tolerated with no major adverse effects, moreover the thrombocytopenia occurrence was significantly lower in MRG (p = 0.005). In MRG, survival increased and mortality risk decreased, although the difference between groups wasn't significant (p = 0.37), which might be related to the small sample-size. Conclusion Our study showed that melatonin is unlikely to reduce mortality among COVID19 patients and with no significant effect on disease-specific biochemical parameters.