Effect of COVID-19 Vaccination on Thyroid Disease in 7 Million Adult and 0.2 Million Adolescent Vaccine Recipients
Authors' conclusion
This extensive, national self-controlled case series analysis found an increased risk of exacerbation of hypothyroidism following COVID-19 vaccination. However, no association was observed between COVID-19 vaccination and an increased risk of most other thyroid diseases. These findings contribute to increasing evidence supporting the safety of COVID-19 vaccination in relation to thyroid health.
Study context
- Population
- Adult and adolescent COVID-19 vaccine recipients, nationwide cohort of South Korea7,579,210 adults · 241,063 adolescents
- Exposure
- 55-day postvaccination period vs baseline period
- Outcome
- IRR of thyroid disease (hyperthyroidism, hypothyroidism, subacute thyroiditis, TED)
- Follow-up
- 55-day postvaccination period
Methodological detailsnationwide, conditional Poisson regression
- Nationwide
- Conditional Poisson regression
Main finding
As reported in the abstract
Thyroid disease in adults
Postvaccination period vs Baseline periodIncidence rate ratio (95% CI)
Hyperthyroidism, after first dose
0.98(0.89–1.09)
Hypothyroidism, after first dose
0.88(0.84–0.93)
Subacute thyroiditis, after first dose
1.27(0.94–1.72)
TED, after first dose
0.68(0.50–0.93)
Hyperthyroidism, after second dose
0.96(0.87–1.06)
Hypothyroidism, after second dose
0.96(0.92–1.02)
Subacute thyroiditis, after second dose
1.32(0.96–1.80)
TED, after second dose
1.06(0.81–1.38)
Observational data: associations, not effects.
Further findings
Hyperthyroidism recurrence and hypothyroidism exacerbation (adults)
- Risk of hyperthyroidism recurrence did not increase after vaccination
- Increased risk of hypothyroidism exacerbation
Subgroups by age, sex and vaccine type
- No significant differences in incidence of thyroid diseases
Thyroid disease in adolescents aged 12 to 17 years
- No increase in risk of thyroid disease after vaccination
Original publication
Effect of COVID-19 Vaccination on Thyroid Disease in 7 Million Adult and 0.2 Million Adolescent Vaccine Recipients. J Clin Endocrinol Metab. Published 9 December 2024. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →