The relationship between demographic indicators and mortality rate of COVID-19 disease comparatively and retrospectively in different waves of COVID-19 disease in Iran

Coronavirus disease-19 (COVID-19) is a novel emerging infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARSCoV-2). In this study, we aimed to examine the relationship between demographic indicators and mortality rates in Covid-19 disease in different Covid-19 waves in Iran. In this retrospective cross-sectional study, the study population consisted of 9874 patients of Covid-19 admitted to Hazrat Rasoul Akram Hospital of Tehran, from the beginning of the disease to the end of the fifth wave. Demographic variables such as age and sex as well as clinical variables such as hospitalization date and mortality rate were collected and evaluated. The analysis was performed using SPSS software version 26. The mean age of 9874 participants was 58.9 +/- 17.0 years. In this study 5510 (55.8%) of patients were male. 1762 (17.8%) patients died. The fifth wave had the highest number of patients (31.1%) and the trend in the number of patients was increasing from wave second to fifth. However, the percentage of death was lower in waves fourth (14.5%) and fifth (15.3%). The mean age of deceased patients was significantly greater than alive patients (69.25 +/- 14.60 vs. 56.76 +/- 16.75, P=0.0001). The frequency of male deaths was significantly higher than female deaths (P=0.0001). The results of the present study indicate that the frequency of mortality in recent waves, despite a significant increase in hospitalization, has been decreased. It can also be said that mortality increases with age as well as male gender, and males are more prone to death due to covid-19 disease with age. Copyright © 2022 Ondokuz Mayis Universitesi. All rights reserved.