Risk of thrombotic complications in influenza versus COVID-19 hospitalized patients

Milou A M Stals; Marco J J H Grootenboers; Coen van Guldener; Fleur H J Kaptein; Sander J E Braken; Qingui Chen; Gordon Chu; Erik M van Driel; Antonio Iglesias Del Sol; Evert de Jonge; K Merijn Kant; Fleur Pals; Myrthe M A Toorop; Suzanne C Cannegieter; Frederikus A Klok; Menno V Huisman; Dutch COVID & Thrombosis Coalition (DCTC)

doi:10.1002/rth2.12496

Risk of thrombotic complications in influenza versus COVID-19 hospitalized patients

Res Pract Thromb Haemost. 2021 Apr 8;5(3):412-420. doi: 10.1002/rth2.12496. eCollection 2021 Mar.

Authors

Milou A M Stals¹, Marco J J H Grootenboers², Coen van Guldener³, Fleur H J Kaptein¹, Sander J E Braken¹, Qingui Chen⁴, Gordon Chu¹, Erik M van Driel⁵, Antonio Iglesias Del Sol⁶, Evert de Jonge⁷, K Merijn Kant⁸, Fleur Pals¹, Myrthe M A Toorop⁴, Suzanne C Cannegieter^{1

4}, Frederikus A Klok¹, Menno V Huisman¹; Dutch COVID & Thrombosis Coalition (DCTC)

Affiliations

¹ Department of Thrombosis and Hemostasis Leiden University Medical Center Leiden The Netherlands.
² Department of Pulmonology Amphia Hospital Breda The Netherlands.
³ Department of Internal Medicine Amphia Hospital Breda The Netherlands.
⁴ Department of Clinical Epidemiology Leiden University Medical Center Leiden The Netherlands.
⁵ Department of Intensive Care Medicine Alrijne Hospital Leiderdorp The Netherlands.
⁶ Department of Internal Medicine Alrijne Hospital Leiderdorp The Netherlands.
⁷ Department of Intensive Care Medicine Leiden University Medical Center Leiden The Netherlands.
⁸ Department of Intensive Care Medicine Amphia Hospital Breda The Netherlands.

Abstract

Background: Whereas accumulating studies on patients with coronavirus disease 2019 (COVID-19) report high incidences of thrombotic complications, large studies on clinically relevant thrombosis in patients with other respiratory tract infections are lacking. How this high risk in COVID-19 patients compares to those observed in hospitalized patients with other viral pneumonias such as influenza is unknown.

Objectives: To assess the incidence of venous and arterial thrombotic complications in hospitalized patients with influenza as opposed to that observed in hospitalized patients with COVID-19.

Methods: This was a retrospective cohort study; we used data from Statistics Netherlands (study period: 2018) on thrombotic complications in hospitalized patients with influenza. In parallel, we assessed the cumulative incidence of thrombotic complications-adjusted for competing risk of death-in patients with COVID-19 in three Dutch hospitals (February 24 to April 26, 2020).

Results: Of the 13 217 hospitalized patients with influenza, 437 (3.3%) were diagnosed with thrombotic complications, versus 66 (11%) of the 579 hospitalized patients with COVID-19. The 30-day cumulative incidence of any thrombotic complication in influenza was 11% (95% confidence interval [CI], 9.4-12) versus 25% (95% CI, 18-32) in COVID-19. For venous thrombotic (VTC) complications and arterial thrombotic complications alone, these numbers were, respectively, 3.6% (95% CI, 2.7-4.6) and 7.5% (95% CI, 6.3-8.8) in influenza versus 23% (95% CI, 16-29) and 4.4% (95% CI, 1.9-8.8) in COVID-19.

Conclusions: The incidence of thrombotic complications in hospitalized patients with influenza was lower than in hospitalized patients with COVID-19. This difference was mainly driven by a high risk of VTC complications in the patients with COVID-19 admitted to the Intensive Care Unit. Remarkably, patients with influenza were more often diagnosed with arterial thrombotic complications.

Keywords: COVID‐19; human; incidence; influenza; pneumonia; thrombosis; viral.