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Comparing Coronavirus Disease 2019 (COVID-19) Pandemic Waves in Hospitalized Patients: A Retrospective, Multicenter,
Yaron Niv1,2, Noa Eliakim-Raz3, Yaron Bar-Lavi4
1Division of Quality and Safety, Ministry of Health, Jerusalem, Israel.
Insights
Hospitalized patients during the third wave of COVID-19 in Israel faced significantly higher mortality and required more advanced respiratory support, including invasive ventilation and ECMO, compared to earlier pandemic waves.
Area of Science:
- Infectious Diseases
- Epidemiology
- Critical Care Medicine
Background:
- The first case of Coronavirus disease 2019 (COVID-19) in Israel was identified in late February 2020.
- By June 2021, Israel reported over 842,000 confirmed cases and 6,400 deaths.
- This study focuses on comparing COVID-19 pandemic waves prior to widespread immunization.
Purpose of the Study:
- To describe the demographic and clinical characteristics of hospitalized COVID-19 patients in Israel.
- To compare the severity and outcomes of COVID-19 across different pandemic waves.
- To analyze trends in mortality and respiratory support utilization.
Main Methods:
- A multicenter, retrospective cohort study design was employed.
- A random sample of 6,329 patients from 22,302 hospitalized individuals was selected.
- Eligible patients were categorized into two periods: the first (waves 1 & 2) and the second (wave 3), with 3,582 and 1,106 patients respectively.
Main Results:
- Thirty-day mortality was significantly higher in the second period (25.20%) compared to the first period (13.68%).
- The utilization of invasive mechanical ventilation increased from 9.19% in the first period to 14.21% in the second period.
- Extracorporeal membrane oxygenation (ECMO) use more than doubled in the second period compared to the first.
Conclusions:
- COVID-19 patients in the second pandemic period (third wave) experienced a 1.5 to 2 times higher rate of invasive ventilation, ECMO use, and mortality.
- Patients in the second period presented with more severe illness.
- The findings indicate a more severe disease course and worse outcomes during the third wave of the pandemic in Israel.
Background:
Coronavirus disease 2019 was first diagnosed in Israel at the end of February 2020. By the end of June 2021, there were 842 536 confirmed cases and 6428 deaths. Our aim in this multicenter, retrospective, cohort study is to describe the demographic and clinical characteristics of hospitalized patients and compare the pandemic waves before immunization.
Methods:
Of 22 302 patients hospitalized in general medical centers, we randomly selected 6329 for the study. Of these, 3582 and 1106 were eligible for the study in the first period (first and second waves) and in the second period (third wave), respectively.
Results:
Thirty-day mortality was higher in the second period than in the first period, 25.20% vs 13.68% (P < .001). Invasive mechanical ventilation supported 9.19% and 14.21% of patients in the first period and second period, respectively. Extracorporeal membrane oxygenation (ECMO) was used more than twice as often in the second period.
Conclusions:
Invasive ventilation, use of ECMO, and mortality rate were 1.5 to 2 times higher in the second period than in the first period. In the second period, patients had a more severe presentation and higher mortality than those in the first period.
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