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

Stals, M.A.M.; Grootenboers, M.J.J.H.; Guldener, C. van; Kaptein, F.H.J.; Braken, S.J.E.; Chen, Q.G.; ... ; Dutch COVID Thrombosis Coalition (2021)

Article / Letter to editor

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.

• COVID-19
• human
• incidence
• influenza
• pneumonia
• thrombosis
• viral

• All authors: Stals, M.A.M.; Grootenboers, M.J.J.H.; Guldener, C. van; Kaptein, F.H.J.; Braken, S.J.E.; Chen, Q.G.; Chu, G.; Driel, E.M. van; Sol, A.I. del; Jonge, E. de; Kant, K.M.; Pals, F.; Toorop, M.M.A.; Cannegieter, S.C.; Klok, F.A.; Huisman, M.V.; Dutch COVID Thrombosis Coalition
• Date: 2021-04-08
• Journal: Research and Practice in Thrombosis and Haemostasis
• Volume: 5
• Issue: 3
• Pages: 412 - 420
• DOI: doi:10.1002/rth2.12496
• Link: https://onlinelibrary.wiley.com/doi/10.1002/rth2.12496