Investigation of all-cause mortality and associated factors in patients diagnosed with COVID-19: A Cohort Study

Objective: This study aims to investigate the extent and associated factors of all-cause mortality in patients diagnosed with COVID-19 in a hospital for over a one-year follow-up period. Methods: This cohort study was conducted on the patients who applied and tested positive for SARS-CoV-2 in the Dokuz Eylul University Hospital which is a large tertiary healthcare facility in Izmir, Turkey, between 19.03.2020 and 31.05.2021. The study included 8955 adult patients with a positive SARS-CoV-2 PCR test. Kaplan-Meier survival analysis and Cox regression models were used to examine the relationships between demographic and clinical characteristics and mortality. Results: The cumulative all-cause mortality rate was 4.7% in Covid 19 patients. Patients over 80 years old had a significantly higher risk of death compared to those younger than 50 years old (aHR:22.3; 95% CI: 10.4-47.7). Current or ex-smokers had a higher risk of death compared to non-smokers (aHR: 1.6; 95% CI: 1.1-2.4). Patients without any complaints before diagnosis had a higher risk of death compared to those with three or more complaints (aHR: 1.7; 95% CI: 1.2-2.6). Patients hospitalized in the intensive care unit had a significantly higher risk of death compared to outpatients (aHR: 62.3; 95% CI: 37.6-101.9). Conclusions: In COVID-19 patients, the cumulative all-cause mortality rate was 4.7%; age, smoking, having a chronic disease, number of complaints prior to diagnosis, and admission status were identified as independent risk factors. Elderly people with chronic diseases need to be prioritized for preventive measures.