Fatemeh Shahbazi - MSc, Department of Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran- Students Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
Manoochehr Karami - PhD, Department of Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran- Modeling of Noncommunicable Diseases Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
Mohammad Mirzaei - MSc, Deputy Minister of Health, Hamadan University of Medical Sciences, Hamadan, Iran
Younes Mohammadi - PhD, Department of Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran- Social Determinants of Health Research Center, Hamadan University of Medical Sciences, Hamadan, Iran

Background: Coronavirus disease ۲۰۱۹ (COVID-۱۹) is a contagious disease caused by a newlyidentified coronavirus. Our knowledge about the survival rate and prognostic factors of the diseaseis not established well. Therefore, this study aimed to identify the risk factors associated with thesurvival of COVID-۱۹ cases in Hamadan province, West of Iran.Study design: A retrospective cohort studyMethods: This retrospective cohort study was performed in Hamadan province, West of Iran. Thestudy included patients that referred to the provincial hospitals from February ۲۰ to September ۲۰,۲۰۲۰. The follow-up of each subject was calculated from the date of onset of respiratory symptomsto the date of death. Demographic and clinical characteristics were extracted from patients’ medicalrecords. Kaplan-Meier method, Flemington-Harrington test, and Cox regression were used for dataanalysis.Results: The overall ۱, ۵, ۱۰, ۲۰, ۳۰ and ۴۹-day survival rates were estimated at ۹۹.۵۷%, ۹۵.۶۱%,۹۱.۱۵%, ۸۷.۳۴%, ۸۶.۹۱%, and ۸۶.۷۴%, respectively. Furthermore, survival time showed asignificant association with age, gender, history of traveling to contaminated areas, co-morbidity,neoplasms, chronic diseases, and hospital units.Conclusions: In conclusion, elderly people, male gender, and comorbidities presented a greaterrisk of death. Therefore, it is important to pay more attention to this group of people to reduce theincidence and consequences after infection.

COVID-۱۹, Epidemiology, Iran, Mortality, Survival