Investigation of all-cause mortality and associated factors in patients diagnosed with COVID-19: A Retrospective Cohort Study
Abstract
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 retrospective 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 risk of all-cause mortality is higher in the elderly, smokers, individuals admitted to medical or intensive care services, and those with a decreasing number of pre-diagnostic complaints. Monitoring patients with long follow-up periods and determining the course of illness and cause of death are important for understanding the natural course of COVID-19.
Keywords
COVID-19, mortality, Follow-Up Study
Supporting Institution
There is no Supporting Institution.
Project Number
The study was not carried out within the scope of the project.
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