Cohort studyindependent cross-checkabstract checked★ key study I-ORG-123 in-depth review
Childhood tonsil surgery and later autoimmune disease in Korea
Association between childhood tonsillectomy and increased risk of autoimmune disease: a nationwide population-based cohort study.
Overview
Chang YS et al.. Front Med (Lausanne) 2026 · PMID 42643288 · DOI 10.3389/fmed.2026.1892240
Children who had the surgery later had about 32% more autoimmune diseases than similar children who did not, but this does not prove the surgery caused them.
Does the study support the specific claim? Partly · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Check whether childhood tonsil/adenoid surgery is linked to autoimmune disease
- How was the study done?
National cohort
- How many people, animals or samples were studied?
84,030 operated and 336,120 non-operated children
- What was actually found?
Autoimmune disease 86.5 vs 65.3 per 100,000 person-years
- How large was the observed effect?
HR 1.32 (1.23-1.41)
- What do the results mean in everyday life?
Small absolute increase; cause unclear
- What are the study's limitations?
Claims data, residual confounding
- What does it say about Elawady's specific claim?
Supports the association, not proof of causation
- Do the results apply to Germany and Europe?
Moderate
- What can explicitly not be concluded from this study?
Cannot separate surgery from underlying immune tendency
Scientific in-depth review
1. Full reference
- Authors
- Chang YS et al.
- Journal
- Front Med (Lausanne)
- Year
- 2026
- Identifier
- PMID 42643288 DOI 10.3389/fmed.2026.1892240
- Verification
- verified – PubMed efetch 2026-10-26; Crossref works API 2026-10-26
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
Not stated in abstract.
2. Research question
Is childhood tonsillectomy and/or adenoidectomy associated with later autoimmune disease?
3. Study design and population
- Study design
- Cohort study – Nationwide claims-based cohort (Korean HIRA), age- and sex-matched 1:4
- Population
Children 0-12 years treated for tonsillar or adenoid disease in 2007-2008
- Country
South Korea
- Period
Surgery 2007-2013; follow-up to June 2023 (mean 15.6 years)
- Sample size
84,030 operated; 336,120 non-operated
- Inclusion and exclusion criteria
Children with care for tonsillar/adenoid disease
4. Methods and endpoints
- Exposure / intervention
Tonsillectomy and/or adenoidectomy
- Comparator
Non-operated children with tonsillar/adenoid disease (age- and sex-matched)
- Endpoints
Incident autoimmune diseases
- Statistical methods
Cox proportional hazards
5. Actual results
- Results
Incidence 86.5 vs 65.3 per 100,000 person-years. Overall autoimmune disease HR 1.32 (95% CI 1.23-1.41). SLE HR 2.20 (1.55-3.13), ankylosing spondylitis 1.35 (1.06-1.72), JIA 1.69 (1.19-2.39), type 1 diabetes 1.34 (1.14-1.58), Hashimoto 1.39 (1.22-1.57), Graves 1.38 (1.22-1.56).
- Absolute risks
21.2 extra cases per 100,000 person-years (86.5 vs 65.3).
- Authors' conclusion
Childhood tonsillectomy and/or adenoidectomy was associated with increased risk of autoimmune disease later in life.
6. Strengths
- Very large
- Comparison group also had tonsillar/adenoid disease
- Long follow-up
7. Weaknesses
- Claims data
- Matching only by age and sex
- Residual confounding by disease severity and familial factors
8. Risk of bias
- Orienting tool
- ROBINS-E
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Better comparator than general population, but severity of tonsil disease and family susceptibility not controlled.
9. Assessment of the statistical interpretation
Crude rate ratio 1.32 matches the HR; absolute excess about 1 case per 4700 person-years (stats/C-ORG-04_05_06_assoc.py).
10. Relevance to the specific claim
Independent replication of Ji 2016 (A-ORG-02) in another country with a disease-based comparison group.
11. Independent contrary findings
Bager 2019 (I-ORG-124): relatives of tonsillectomised people also have higher IBD risk, pointing to shared familial factors.
12. Transferability to Germany and Europe
Korean; association pattern similar to Sweden.
13. Overall methodological judgement
Strengthens the evidence that the association is real and reproducible (about 30% relative excess); causation remains unproven and the absolute excess is small.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | high |
| Directness | direct |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Sibling or family-controlled analyses for autoimmune disease.
15. Linked fact checks
- Tonsillectomy increases autoimmune disease by 34% (Ji 2016, 179,875 Swedish patients). – Studies supporting the claim
- Long-term registry data link removal of tonsils, appendix, gallbladder, uterus, ovaries and spleen to higher rates of respiratory disease, autoimmunity, cardiovascular events, gastrointestinal cancers and dementia; each organ does work the body never fully replaces. – Studies supporting the claim