Autor:innen:
Maroussia Roelens (Geneva | CH)
Alexis Martin (Geneva | CH)
Beatriz Vidondo (Bern | CH)
Anne Iten (Geneva | CH)
Alexia Cusini (Chur | CH)
Domenica Flury (St Gallen | CH)
Michael Buettcher (Lucerne | CH)
Franziska Zukol (Winterthur | CH)
Carlo Balmelli (Ticino | CH)
Petra Zimmermann (Fribourg | CH)
Nicolas Troillet (Sion | CH)
Danielle Vuichard-Gysin (Münsterlingen | CH)
Peter W. Schreiber (Zurich | CH)
Sara Bernhard-Stirnemann (Aarau | CH)
Sarah Tschudin Sutter (Basel | CH)
Yvonne Nussbaumer-Ochsner (Schaffhausen | CH)
Rami Sommerstein (Lucerne | CH)
Roman Gaudenz (Stans | CH)
Jonas Marschall (Bern | CH)
Filipe Maximiano (Bern | CH)
Brian Fricker (Bern | CH)
Gertraud Schuepbach (Bern | CH)
Stephan Harbarth (Geneva | CH)
Andreas Widmer (Basel | CH)
Miriam Vazquez (Bern | CH)
Lauro Damonti (Bern | CH)
Christoph Kuhm (Münsterlingen | CH)
Thomas Riedel (Chur | CH)
Ulrich Heininger (Basel | CH)
Christoph Berger (Zurich | CH)
Natascia Corti (Zurich | CH)
Anita Uka (Fribourg | CH)
Anita Niederer-Loher (Saint Gall | CH)
Philipp Kaiser (Lucerne | CH)
Stefan Kuster (Bern | CH)
Mirjam Maeusezahl (Bern | CH)
Monica Wymann (Bern | CH)
Claudia Scheuter (Bern | CH)
Céline Gardiol (Bern | CH)
Olivia Keiser (Geneva | CH)
Introduction and aim
The assessment of COVID-19 associated mortality is crucial to evaluate the impact of the pandemic and to assess the effectiveness of measures. We aimed to investigate trends in COVID-19 related mortality over time in Switzerland, using data from the COVID-19 Hospital-based Surveillance (CH-SUR) database.
Methods
CH-SUR is a prospective hospital surveillance system for COVID-19 patients from 21 hospitals. Considering four different time periods corresponding to the different waves of COVID-19 in Switzerland (Spring, Summer, Autumn 2020, Winter 2021), we calculated crude and adjusted mortality rates and performed survival analyses using Fine & Gray survival models accounting for competing risks. Similar models were conducted for patients admitted to ICU.
Results and Discussion
Overall 16,967 episodes and 2,307 deaths were recorded. Crude in-hospital mortality rates were 15.6% in the 1st and 14.4% in the 2nd wave; for ICU patients it was 24% and 31.3% respectively. Patients were slightly older (median 73 vs 63 years), more likely male (59.9 vs 58.5%) and more comorbid (62 vs 60%) in the 2nd than the 1st wave. Dexamethasone use also increased during the second wave. The adjusted risk of death was lower for hospitalised patients during the 2nd compared to the 1st wave (HR 0.75, 95% CI 0.73 – 0.77). In contrast, the risk of death in patients admitted to ICU was higher during the 2nd wave (HR 1.62, 95% CI 1.54 - 1.70) and patients with invasive ventilation also had a higher mortality (HR 2.10, 95% CI 1.99 - 2.20).
Conclusion
The lower mortality in the second wave compared to first wave was not explained by changes in demographic characteristics, but may be explained by more effective patient care. Especially in the western part of Switzerland, ICU capacity in several cantons reached almost its limits during several weeks in the 2nd wave, which might have contributed to the higher mortality of patients in ICU.