Heart failure & cardiomyopathiesCohort study
Prognostic Factors Associated with Fatal Outcomes in COVID-19 Vaccine-Related Myocarditis
- retrospective analysis of a pharmacovigilance database
- Japanese Adverse Drug Event Report database
- 2021 to 2024
Authors' conclusion
Older age was associated with higher odds of reported fatal outcomes among VRM reports in JADER. Female sex, delayed onset, and comorbidities were more common among reports with fatal outcomes. These exploratory findings require validation in clinically adjudicated studies.
Study context
- Population
- COVID-19 vaccine-related myocarditis reports in the Japanese Adverse Drug Event Report databasereports including myocarditis among 31,022 reports listing COVID-19 vaccines as suspected drug, outcome data available for 863 reports
- Participants
- 1,041 participants
- Exposure
- death vs survival groups based on recorded outcome information
- deathn = 97
Main finding
As reported in the abstract
Myocarditis reporting with COVID-19 vaccines
reporting odds ratio [ROR]
31.3, 95% CI 29.0-33.8
Observational data: associations, not effects.
Further findings
Time from vaccination to myocarditis onset
- median time
- 2 (1-4) days
- most events occurring within 7 days
Characteristics of vaccine-related myocarditis (VRM) reports
- men
- 77.8%
- ≤39 years old
- 68.6%
Death recorded (of 863 reports with outcome data)
- death
- 97 reports (11.2% [95% CI, 9.3%-13.5%])
Factors associated with reported fatal outcomes
- age ≥70 years independently associated with reported fatal outcomes (multivariable logistic regression), OR
- 8.67, 95% CI 4.41-17.3; P < 0.001
- Reported fatal outcomes more frequent in women, patients aged ≥70 years, those with delayed onset (≥8 days after COVID-19 vaccination), and those with ≥1 comorbidities
Original publication
Prognostic Factors Associated with Fatal Outcomes in COVID-19 Vaccine-Related Myocarditis. ESC Heart Fail. Published 16 September 2026. doi:10.1093/eschf/xvag239
Summarised from the published abstract; every number is checked against it