Survival Analyses of COVID-19 Patients in a Turkish Cohort: Comparison between Using Time to Death and Time to Release

COVID-19 Survival Analysis Cause-specific Hazard Ratio Case-control Analysis.

Authors

  • Sirin Cetin Department of Biostatistics, Faculty of Medicine, Tokat Gaziosmanpaşa University,, Turkey
  • Ayse Ulgen
    ayshe.ulgen@global.t-bird.edu
    Department of Biostatistics, Faculty of Medicine, Girne American University, Karmi,, Cyprus
  • Pervin Ozlem Balci Department of Medical Microbiology, Tokat State Hospital, Tokat,, Turkey
  • Hakan Sivgin Department of Internal Medicine, Tokat State Hospital, Tokat,, Turkey
  • Meryem Cetin Department of Medical Microbiology, Faculty of Medicine, Tokat Gaziosmanpaşa University,, Turkey
  • Sevdiye Sivgin Department of Anesthesiology and Reanimation, Tokat State Hospital, Tokat,, Turkey
  • Wentian Li The Robert S. Boas Center for Genomics and Human Genetics, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY,, United States

Downloads

Survival analyses of COVID-19 data has its own unique features, in particular, the existence of two distinct events: death and release from the hospital within a very short period of time. This multiple-event situation belongs to a type where the occurrence of the first event prevents the second event to happen, and vice versa. We carried out two cause-specific univariate Cox regression survival analyses, one for time-to-death and another for time-to-release. Each survival analysis is further split into one for onset of symptom to event time and another for hospitalization to event time. We have also carried out a case-control (death vs. release) analysis without considering the time to event information. We observed that risk factors can be detected by either case-control or survival analysis, even though the goal of the two is quite different. We also observed that the two survival analyses may not both reveal a factor being a risk factor, but only one of them does. We prefer this two rounds of Cox regressions over mixture cure model which is only focused on time-to-death events which usually are sample size limited. By utilizing time-to-release events may greatly increase the sample size needed for revealing risk factors for COVID-19.

 

Doi: 10.28991/SciMedJ-2021-03-SI-1

Full Text: PDF