Concurrent analysis of hospital stay durations and mortality of emerging severe acute respiratory coronavirus virus 2 (SARS-CoV-2) variants using real-time electronic health record data at a large German university hospital

Abstract

Multistate methodology proves effective in analyzing hospitalized coronavirus disease 2019 (COVID-19) patients with emerging variants in real time. An analysis of 2,548 admissions in Freiburg, Germany, showed reduced severity over time in terms of shorter hospital stays and higher discharge rates when comparing more recent phases with earlier phases of the pandemic.

Fig. 1.

Stacked probability plots stratified by pandemic phases of 2,548 COVID-19 admissions at the University Medical Center Freiburg, Germany. SARS-CoV-2 wild-type period, January 27, 2020–February 14, 2021; SARS-CoV-2 α (alpha) period, February 15, 2021–June 20, 2021; SARS-CoV-2 δ (delta) period, June 21, 2021–December 26, 2021; SARS-CoV-2 ο (omicron) period, December 27, 2021–March 1, 2022. Calendar periods are a surrogate for the variants and treatment options in the specified period. Distance between lines represent the proportion of patients in a particular state on day since hospital admission. Note. Discharge, discharged alive from hospital; nonsevere, normal hospital ward; severe, intensive care unit; death, death in hospital.