Post-SARS-CoV-2-vaccination Cerebral Venous Sinus Thrombosis: an analysis of cases notified to the European Medicines Agency.

BACKGROUND

Cerebral venous sinus thrombosis (CVST) has been described after vaccination against SARS-CoV-2. We report clinical characteristics of 213 post-vaccination CVST cases notified to the European Medicines Agency (EMA).

METHODS

Data on Adverse Drug Reactions after SARS-CoV-2 vaccination notified until 8 April 2021 under the Medical Dictionary for Regulatory Activities Term 'Central nervous system vascular disorders' were obtained from the EudraVigilance database. We compared post-vaccination CVST to 100 European patients with CVST from before the COVID-19 pandemic derived from the International CVST Consortium.

RESULTS

We identified 213 CVST cases: 187 after AstraZeneca/Oxford (ChAdOx1 nCov-19), vaccination and 26 after a mRNA vaccine (25 Pfizer/BioNTech, BNT162b2 and 1 Moderna, mRNA-1273). Thrombocytopenia was reported in 107/187 CVST cases (57%, 95%CI 50-64%) in the ChAdOx1 nCov-19 group, in none in the mRNA vaccine group (0%, 95%CI 0-13%), and in 7/100 (7%, 95%CI 3-14%) in the pre-COVID-19 group. In the ChAdOx1 nCov-19 group, there were 39 (21%) reported COVID-19 PCR tests performed within 30 days of CVST symptom onset, and all were negative. Of the 117 patients with a reported outcome in the ChAdOx1 nCov-19 group, 44 (38%, 95%CI 29-47%) had died, compared to 2/10 (20%, 95%CI 6-51%) in the mRNA vaccine group and 3/100 (3%, 95%CI 1-8%) in the pre-COVID-19 group. Mortality among patients with thrombocytopenia in the ChAdOx1 nCov-19 group was 49% (95%CI 39-60%).

CONCLUSIONS

CVST occurring after ChAdOx1 nCov-19 vaccination has a clinical profile distinct from CVST unrelated to vaccination. Only CVST after ChAdOx1 nCov-19 was associated with thrombocytopenia.