Time-to-death analysis of COVID-19 pandemic patients: A case study of Jimma Zone, Southwest Ethiopia.

Abstract

Introduction: COVID-19 is an infectious disease caused by severe acute respiratory syndrome coronavirus-2. It was first reported in December 2019 in Wuhan, China, and has since spread to pandemic proportions. Since then, the virus has rapidly spread to the world and has caused over 637.351 million confirmed cases, more than 6,604 million deaths, and more than 616.952 million recoveries worldwide as of November 05, 2022. The accelerated failure time model which is an alternative to the proportional hazard model when the proportional hazard assumptions doesn’t hold was used to analyze time of event, death from COVID-19 pandemic. Objective: This study aimed to analyze the time-to-death of COVID-19 pandemic patients in Jimma Zone, southwest Ethiopia. Methodology: A retrospective cohort study was conducted on 809 COVID-19 patients who admitted to Jimma university medical center and Shenen gibe generalized hospital from May 16, 2020 to March 9, 2022 in Jimma Zone, southwest Ethiopia. KaplanMeier plots and Log-Rank test were used to compare the survival experience of different categories and semi-parametric survival model and acceleration failure time models were employed to identify survival time of the patients. The performances of acceleration failure time models were compared using Akakie Information Criteria. Results: From 809 patients, 135(16.7%) died in the follow-up period. Log-logistic acceleration failure time model is better fit the data than other models. The result of this model shows that the survival time of COVID-19 patients significantly affected by age, comorbidity, status at admission, HIV/AIDS, symptom at admission, intranasal oxygen use and diabetes. Conclusions: The AFT model is a more valuable and realistic alternative to the Cox PH model in situations where PH assumption cannot hold and therefore should be considered as an alternative to the Cox PH for analyzing the time to death of COVID-19 patients. Older age, comorbidity, moderate or severe status at admission, HIV/AIDS, being asymptomatic at admission, intranasal oxygen use, and diabetes are factors that accelerate time to death in COVID-19 patients