Arrhythmias & electrophysiologyCohort study
Thromboembolism after coronavirus disease 2019 vaccination in atrial fibrillation/flutter: a self-controlled case series study
- Self-controlled case series study
- modified self-controlled case series
- nationwide-linked database
Authors' conclusion
In patients with AF/AFL, COVID-19 vaccination was generally not associated with an increased risk of thrombo-embolic events.
Study context
- Population
- Individuals aged ≥12 years with AF/atrial flutter, vaccinated or unvaccinated, South Korea National Health Insurance Service database, February–December 2021final analysis
- Participants
- 124,127 individuals
- Exposure
- Risk period vs Unexposed control period
- Outcome
- Composite of thromboembolic events (ischaemic stroke, TIA, systemic thromboembolism)
- Follow-up
- 0-21 days following COVID-19 vaccination
Main finding
Thromboembolic events · within 21 days after vaccination
Incidence rate ratio
0.93
95% CI 0.77–1.12
Risk period vs Unexposed control period
IRR 0.93 (95% CI 0.77–1.12)
As reported in the abstract
Observational data: associations, not effects.
Further findings
Thrombo-embolic events by sex, age or vaccine type (subgroups)
- No significant risk variations by sex, age or vaccine type
Thrombo-embolic events, patients without anticoagulant therapy (subgroup) · within 21 days after COVID-19 vaccination
- IRR following vaccination, patients without anticoagulant therapy
- 1.88 (95% CI 1.39-2.54)
Original publication
Thromboembolism after coronavirus disease 2019 vaccination in atrial fibrillation/flutter: a self-controlled case series study. Eur Heart J. Published 12 July 2024. doi:10.1093/eurheartj/ehae335
Summarised from the published abstract; every number is checked against it