Cohort studycited by the Tayebat archiveabstract only checked★ key study A-ORG-01 in-depth review
Danish children: tonsil/adenoid removal and later illness
Association of Long-Term Risk of Respiratory, Allergic, and Infectious Diseases With Removal of Adenoids and Tonsils in Childhood.
Overview
Byars SG et al.. JAMA Otolaryngol Head Neck Surg 2018 · PMID 29879264 · DOI 10.1001/jamaoto.2018.0614
Children who had the operations had more respiratory illnesses later (2-3 times for upper airway disease), but the study cannot prove the operation caused it.
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?
Long-term risk
- How was the study done?
Register cohort
- How many people, animals or samples were studied?
1.19 million
- What was actually found?
Associations with later respiratory/infectious/allergic disease
- How large was the observed effect?
RR 1.99-2.72; infections +2.14% absolute
- What do the results mean in everyday life?
A reason to avoid unnecessary operations
- What are the study's limitations?
Confounding
- What does it say about Elawady's specific claim?
Supports a cautious approach, not a ban
- Do the results apply to Germany and Europe?
Directly European
- What can explicitly not be concluded from this study?
That surgery causes the diseases
Scientific in-depth review
1. Full reference
- Authors
- Byars SG, Stearns SC, Boomsma JJ
- Journal
- JAMA Otolaryngol Head Neck Surg
- Year
- 2018
- Identifier
- PMID 29879264 DOI 10.1001/jamaoto.2018.0614 · PMC6145787
- Verification
- verified – PubMed E-utilities efetch, 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
COI: not stated in record | Grants: none listed
2. Research question
Long-term disease risks after childhood adenoidectomy, tonsillectomy, adenotonsillectomy
3. Study design and population
- Study design
- Cohort study – Population-based register cohort with stratified Cox regression
- Population
Children born in Denmark 1979-1999
- Country
Denmark
- Period
Registers to 2009 (follow-up to age 10-30)
- Sample size
Up to 1,189,061 (17,460 adenoidectomy; 11,830 tonsillectomy; 31,377 adenotonsillectomy)
- Inclusion and exclusion criteria
Exposed if surgery in first 9 years; cases/controls selected so that pre-surgery health did not differ significantly
4. Methods and endpoints
- Exposure / intervention
Adenoidectomy/tonsillectomy/adenotonsillectomy
- Comparator
Non-operated children
- Endpoints
ICD-8/10 diseases up to age 30
- Statistical methods
Stratified Cox, 18 covariates
5. Actual results
- Results
Upper respiratory tract disease RR 1.99 (1.51-2.63) after adenoidectomy and RR 2.72 (1.54-4.80) after tonsillectomy. Adenotonsillectomy: infectious diseases RR 1.17 (1.10-1.25), absolute risk increase 2.14%. Long-term risks for conditions the surgeries aim to treat often did not differ significantly.
- Absolute risks
Infectious disease: absolute increase 2.14% after adenotonsillectomy; other absolute risks not in abstract
- Authors' conclusion
Surgeries associated with increased long-term respiratory, infectious and allergic disease risks; confounding may not be fully accounted for.
6. Strengths
- Very large national registers
- Long follow-up
- Adjustment for 18 covariates
7. Weaknesses
- Confounding by indication (children operated for recurrent infections/obstruction may be prone to respiratory disease)
- Wide CIs for specific outcomes
- Many outcomes tested
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
Observational; residual confounding by indication acknowledged by authors.
9. Assessment of the statistical interpretation
Relative risks are large for rare outcome categories; absolute risk differences small (2.14% for infections).
10. Relevance to the specific claim
Main evidence for the tonsil/adenoid harm claim.
11. Independent contrary findings
CHAT RCT (A-ORG-03), Cochrane (I-ORG-04), NATTINA (I-ORG-05) show short-term benefits in selected patients.
12. Transferability to Germany and Europe
Directly European.
13. Overall methodological judgement
Important signal; causal interpretation uncertain; not yet replicated in other countries (no replication searched systematically).
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | low |
| Directness | direct |
| Reproducibility | not replicated |
| Consistency with the overall evidence | unknown |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | partly correct but over-interpreted |
14. Open questions
Replication outside Denmark; confounding by indication.
15. Linked fact checks
- Adenoids, tonsils and the gallbladder are organs that should not be removed; correcting the diet should be the foundation of treatment. – Studies supporting the claim
- Childhood adenoidectomy or tonsillectomy doubles to triples the risk of upper respiratory disease later in life (Byars 2018, 1.19 million Danish children). – 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
Use by the Tayebat archive
Note: according to the archive, the studies were compiled by the archive operators. Whether Dr. Elawady himself cited this study is not established.
- What the archive says about the study
In 1.19M Danish children, adenoidectomy and tonsillectomy doubled to tripled the risk of upper respiratory disease (RR 1.99 and 2.72).
- A. What was actually studied?
Long-term disease after childhood ENT surgery
- B. What did the authors find?
RR 1.99 and 2.72 for upper respiratory disease; small increases in infections/allergy
- C. What conclusions do the authors themselves draw?
Associated with increased risks; confounding possible; consider long-term risks
- D. What does the archive derive from it?
Presented as surgery causing a 2-3-fold increase.
- E. Is this derivation scientifically justified?
Numbers correct. The headline uses causal wording ('doubled to tripled the risk'); the authors describe associations and state that confounding may not be fully accounted for. Absolute risk (2.14% for infections) is not reported by the archive.
- Adequacy of the interpretation (by the archive)
- partly correct but over-interpreted