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Published on: June 18, 2021
Age-Stratified Risk of Cerebral Venous Sinus Thrombosis After SARS-CoV-2 Vaccination
Katarzyna Krzywicka1, Anita van de Munckhof1, Mayte Sánchez van Kammen1
1From the Departments of Neurology (K.K., A.v.d.M., M.S.v.K., J.M.C.) and Vascular Medicine (M.M.L.), Amsterdam University Medical Centers, University of Amsterdam, the Netherlands; Departments of Neurology (M.R.H., M.A.) and Hematology (J.A.K.H.), Inselspital, Bern University Hospital, University of Bern; Department of Neurology (K.J., E.L., T.T.), Sahlgrenska University Hospital; Department of Clinical Neuroscience (K.J., E.L., T.T.), Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Sweden; Department of Neurology (J.P.), Helsinki University Hospital and University of Helsinki, Finland; Department of Internal Medicine (S.M.) and Radboud Institute of Health Sciences (S.M.), Radboud University Medical Center, Nijmegen, the Netherlands; National Institute for Health Research University College London Hospitals Biomedical Research Centre (M.M.L.), UK; University of Lille (C.C.), Inserm, CHU Lille, U1172-Lille Neuroscience and Cognition, France; Department of Clinical Epidemiology and Biostatistics (A.H.Z.), Amsterdam University Medical Centers, University of Amsterdam, the Netherlands; and Department of Neurosciences and Mental Health (J.M.F., D.A.d.S.), Neurology Service, Hospital de Santa Maria/Centro Hospitalar Universitário Lisboa Norte (CHULN), University of Lisbon, Portugal.
Background And Objectives:
Cerebral venous sinus thrombosis (CVST) as a part of the thrombosis and thrombocytopenia syndrome is a rare adverse drug reaction of severe acute respiratory syndrome coronavirus disease 2 (SARS-CoV-2) vaccination. Estimated background rate of CVST with thrombocytopenia is 0.1 per million per month. We assessed the age-stratified risk of CVST with and without thrombocytopenia after SARS-CoV-2 vaccination.
Methods:
We estimated the absolute risk of CVST with and without thrombocytopenia within 28 days of a first dose of 4 SARS-CoV-2 vaccinations using data from the European Medicines Agency's EudraVigilance database (until June 13, 2021). As a denominator, we used data on vaccine delivery from 31 European countries. For 22.8 million adults from 25 countries, we estimated the absolute risk of CVST after the first dose of ChAdOx1 nCov-19 per age category.
Results:
The absolute risk of CVST within 28 days of first-dose vaccination was 7.5 (95% confidence interval [CI] 6.9-8.3), 0.7 (95% CI 0.2-2.4), 0.6 (95% CI 0.5-0.7), and 0.6 (95% CI 0.3-1.1) per million of first doses of ChAdOx1 nCov-19, Ad26.COV2.S, BNT162b2, and mRNA-1273, respectively. The absolute risk of CVST with thrombocytopenia within 28 days of first dose vaccination was 4.4 (95% CI 3.9-4.9), 0.7 (95% CI 0.2-2.4), 0.0 (95% CI 0.0-0.1), and 0.0 (95% CI 0.0-0.2) per million of first doses of ChAdOx1 nCov-19, Ad26.COV2.S, BNT162b2, and mRNA-1273, respectively. In recipients of ChAdOx1 nCov-19, the absolute risk of CVST, both with and without thrombocytopenia, was the highest in the 18- to 24-year-old group (7.3 per million, 95% CI 2.8-18.8 and 3.7 per million, 95% CI 1.0-13.3, respectively). The risk of CVST with thrombocytopenia in ChAdOx1 nCov-19 recipients was the lowest in the age group ≥70 years (0.2, 95% CI 0.0-1.3). Age <60 years compared to ≥60 years was a predictor for CVST with thrombocytopenia (incidence rate ratio 5.79, 95% CI 2.98-11.24, p < 0.001).
Discussion:
The risk of CVST with thrombocytopenia within 28 days of first-dose vaccination with ChAdOx1 nCov-19 was higher in younger age groups. The risk of CVST with thrombocytopenia was slightly increased in patients receiving Ad26.COV2.S compared with the estimated background risk. The risk of CVST with thrombocytopenia was not increased in recipients of SARS-CoV-2 mRNA vaccines.
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