Abstract: Journal Pre-proof Melatonin as adjunctive therapy in patients admitted to the Covid-19 Elahe Karimpour-razkenari, Fahimeh Naderi-Behdani, Ali Salahshoor, Fatemeh Heydari, Abbas Alipour, Afshin Gholipour Baradari PII: S2049-0801(22)00252-7 DOI: https://doi.org/10.1016/j.amsu.2022.103492 Reference: AMSU 103492 To appear in: Annals of Medicine and Surgery Received Date: 1 February 2022 Revised Date: 3 March 2022 Accepted Date: 6 March 2022 Please cite this article as: Karimpour-razkenari E, Naderi-Behdani F, Salahshoor A, Heydari F, Alipour A, Baradari AG, Melatonin as adjunctive therapy in patients admitted to the Covid-19, Annals of Medicine and Surgery (2022), doi: https://doi.org/10.1016/j.amsu.2022.103492. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2022 Published by Elsevier Ltd on behalf of IJS Publishing Group Ltd. Abstract 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 of criteria, patients who received 15 mg of melatonin daily were called MRG and the rest were ro called NMRG. -p Results: Thirty-one patients were included and analyzed, of which twelve patients were in re MRG. Demographic and clinical characteristics, and laboratory data were similar between two lP 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 na 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 ur occurrence was significantly lower in MRG (p=0.005). In MRG, survival increased and Jo 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. Keywords: melatonin, COVID -19, Mortality, thrombocytopenia