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DOI: 10.1055/a-2762-7934
Pandemic revisited: Characteristics, severity and clinical outcomes of patients hospitalized with SARS-CoV-2-infection in different periods of the pandemic
Charakteristika, Schweregrad und klinischer Ausgang von hospitalisierten Patienten mit SARS-CoV-2-Infektion in verschiedenen Episoden der PandemieAuthors
Abstract
Objective
The SARS-CoV-2-pandemic changed considerably over the course of time in terms of severity and mortality due to the impact of several SARS-CoV-2 variants as well as vaccination and preventive or SARS-CoV-2 specific therapies. We compared patients in two defined periods and analyzed the specific impact of pneumonia, including measures for treatment of respiratory failure.
Methods
This was a single-center retrospective study of patients hospitalized with PCR-confirmed and symptomatic SARS-CoV-2-infection in our center. The pandemic periods 3/2020–12/2021 and 1/2022–3/2023 as well as the periods after establishment of vaccination, preventive and SARS-CoV-2-specific treatments 3/2020–9/2021 and 10/2021–3/2023 were compared.
Results
Overall, n=622 patients were included (n=307 in the first and n=315 in the second pandemic period). Marked differences were found with regard to age, severity of disease and pneumonia, interventions and mortality. Mortality of pneumonia was 25% (27% in the first and 20% in the second pandemic period); 40% of patients (36% patients with pneumonia) who died had not been admitted previously to the ICU. Mortality from pneumonia after exclusion of these patients was 18% (21% in the first and 10% in the second period). Mortality was particularly high in intubated patients with mechanical ventilation (67%).
Conclusions
Our results were comparable with those reported in a national survey and another single center report of a nearby hospital. Treatment restrictions were frequently applied. Risk factors, severity and mortality of SARS-CoV-2-associated pneumonia in the second pandemic period were similar to those reported for community-acquired pneumonia. Excess mortality from mechanical ventilation deserves further investigation.
Zusammenfassung
Fragestellung
Die SARS-CoV-2-Pandemie wies im Verlauf deutliche Veränderungen hinsichtlich Schweregrad und Letalität aufgrund der Virusvarianten, Impfung und präventiver bzw. SARS-CoV-2-spezifscher Therapien erfahren auf. Wir untersuchten die Daten unserer Patienten in zwei definierten Perioden, mit besonderem Fokus auf Pneumonien sowie Interventionen zur Therapie der respiratorischen Insuffizienz.
Methoden
Die retrospektive Analyse umfasste alle Patienten, die in unserem Zentrum mit einer PCR-gesicherten und symptomatischen SARS-CoV-2-Infektion hospitalisiert wurden. Es erfolgte ein Vergleich hinsichtlich zweier definierter Episoden (3/2020–12/2021 und 1/2022–3/2023 [pandemische Episoden] bzw. 3/2020–9/2021 und 10/2021–3/2023 [etablierte Impfung sowie präventive und SARS-CoV-2-spezifische Therapien]).
Ergebnisse
Insgesamt wurden n=622 Patienten mit einer PCR-gesicherten SARS-CoV-2-Infektion eingeschlossen (n=307 in der ersten and n=315 in der zweiten Periode). Hinsichtlich Alter, Schweregrad der Erkrankung und Pneumonie sowie Interventionen und Letalität fanden sich deutliche Unterschiede. Die Letalität der Pneumonie lag bei 27% in der ersten und 20% in der zweiten pandemischen Periode. 40% der Patienten bzw. 33% der Patienten mit Pneumonie wurden im Verlauf der Behandlung nicht auf der ICU aufgenommen. Die Letalität war nach Ausschluss dieser Patienten 18% (21% in der ersten und 10% in der zweiten Episode). Eine Exzess-Letalität bestand bei Patienten mit invasiver Beatmung (67%).
Schlussfolgerungen
Die Ergebnisse waren vergleichbar zu denen einer nationalen Erhebung und einer Untersuchung eines benachbarten Zentrums. Das Therapieziel wurde in vielen Fällen limitiert. Risikofaktoren, Schweregrad und Letalität der SARS-CoV-2-assoziierten Pneumonie der zweiten pandemischen Episode waren vergleichbar zu denen der ambulant erworbenen Pneumonie. Die Exzess-Letalität der invasiven Beatmung verdient weitere Untersuchungen.
Publication History
Received: 30 September 2025
Accepted after revision: 02 December 2025
Article published online:
18 December 2025
© 2025. Thieme. All rights reserved.
Georg Thieme Verlag KG
Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany
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