Differences in clinical characteristics and quantitative lung CT features between vaccinated and not vaccinated hospitalized COVID-19 patients in Italy

Davide Chiumello; Alessandro Tavelli; Lorenzo Serio; Sara De Benedittis; Tommaso Pozzi; Roberta Maj; Mara Velati; Serena Brusatori; Rosanna D'Albo; Carmelo Zinnato; Giulia Marchetti; Luigi Camporota; Silvia Coppola; Antonella D'Arminio Monforte

doi:10.1186/s13613-023-01103-2

Differences in clinical characteristics and quantitative lung CT features between vaccinated and not vaccinated hospitalized COVID-19 patients in Italy

Ann Intensive Care. 2023 Apr 3;13(1):24. doi: 10.1186/s13613-023-01103-2.

Authors

Davide Chiumello^{1

2

3}, Alessandro Tavelli⁴, Lorenzo Serio⁵, Sara De Benedittis⁴, Tommaso Pozzi⁵, Roberta Maj^{6

7}, Mara Velati^{6

7}, Serena Brusatori⁶, Rosanna D'Albo⁶, Carmelo Zinnato⁶, Giulia Marchetti^{5

4}, Luigi Camporota⁸, Silvia Coppola⁹, Antonella D'Arminio Monforte^{5

4}

Affiliations

¹ Department of Anesthesia and Intensive Care, ASST Santi Paolo e Carlo, San Paolo University Hospital, Via Di Rudini 9, Milan, Italy. davide.chiumello@unimi.it.
² Department of Health Sciences, University of Milan, Milan, Italy. davide.chiumello@unimi.it.
³ Coordinated Research Center on Respiratory Failure, University of Milan, Milan, Italy. davide.chiumello@unimi.it.
⁴ Infectious Diseases Unit, Department of Health Sciences, ASST Santi Paolo e Carlo, San Paolo University Hospital, Milan, Italy.
⁵ Department of Health Sciences, University of Milan, Milan, Italy.
⁶ Department of Anesthesiology, Medical University of Göttingen, University Medical Center Göttingen, Göttingen, Germany.
⁷ Department of Anesthesia and Intensive Care, IRCCS San Raffaele Scientific Institute, Milan, Italy.
⁸ Guy's and St Thomas' NHS Foundation Trust, St Thomas' Hospital, London, SE1 7EH, UK.
⁹ Department of Anesthesia and Intensive Care, ASST Santi Paolo e Carlo, San Paolo University Hospital, Via Di Rudini 9, Milan, Italy.

Abstract

Background: To evaluate the differences in the clinical characteristics and severity of lung impairment, assessed by quantitative lung CT scan, between vaccinated and non-vaccinated hospitalized patients with COVID-19; and to identify the variables with best prognostic prediction according to SARS-CoV-2 vaccination status. We recorded clinical, laboratory and quantitative lung CT scan data in 684 consecutive patients [580 (84.8%) vaccinated, and 104 (15.2%) non-vaccinated], admitted between January and December 2021.

Results: Vaccinated patients were significantly older 78 [69-84] vs 67 [53-79] years and with more comorbidities. Vaccinated and non-vaccinated patients had similar PaO₂/FiO₂ (300 [252-342] vs 307 [247-357] mmHg; respiratory rate 22 [8-26] vs 19 [18-26] bpm); total lung weight (918 [780-1069] vs 954 [802-1149] g), lung gas volume (2579 [1801-3628] vs 2370 [1675-3289] mL) and non-aerated tissue fraction (10 [7.3-16.0] vs 8.5 [6.0-14.1] %). The overall crude hospital mortality was similar between the vaccinated and non-vaccinated group (23.1% vs 21.2%). However, Cox regression analysis, adjusted for age, ethnicity, age unadjusted Charlson Comorbidity Index and calendar month of admission, showed a 40% reduction in hospital mortality in the vaccinated patients (HR_adj = 0.60, 95%CI 0.38-0.95).

Conclusions: Hospitalized vaccinated patients with COVID-19, although older and with more comorbidities, presented a similar impairment in gas exchange and lung CT scan compared to non-vaccinated patients, but were at a lower risk of mortality.