Both Adenoids and Tonsils Cause Sleep Disturbances in Children, But Adenotonsillar Hypertrophy Combined is the Most Common Cause
Upper airway obstruction caused by both the tonsils and adenoids together represents the most common anatomical cause of sleep-disordered breathing in children, making adenotonsillectomy (removal of both) the first-line surgical treatment. 1, 2
The Evidence on Which Structure Matters More
Both Structures Contribute Significantly
Adenotonsillar hypertrophy combined is the leading cause of obstructive sleep apnea syndrome (OSA) in children, with peak prevalence occurring at ages 2-8 years. 1, 3
Volumetric measurements demonstrate that both adenoids and tonsils are significantly enlarged in children with OSA compared to matched controls, with both structures contributing to upper airway restriction. 1
Tonsillar hypertrophy shows the highest correlation with disease severity among anatomical factors studied, but this does not mean adenoids are unimportant. 1
Adenoids vs. Tonsils: What the Data Shows
Adenoid size (measured by adenoidal-nasopharyngeal ratio) correlates significantly with the duration and severity of obstructive apneas (r = 0.48, p < 0.01), though not necessarily with the number of apnea episodes. 4
In one study, 91% of children with OSA had adenoid sizes greater than normal means, and 48% had adenoid sizes more than 2 standard deviations above normal. 4
Tonsil size alone does not reliably predict the number or severity of apneas, suggesting that both structures work synergistically to cause obstruction. 4
Why Combined Removal is Standard
Adenoidectomy should be performed concurrently with tonsillectomy in most pediatric cases, as combined adenotonsillectomy provides superior outcomes compared to tonsillectomy alone. 2
The American Academy of Otolaryngology-Head and Neck Surgery recommends adenotonsillectomy (not just one or the other) as first-line treatment for children with OSA in the presence of adenotonsillar hypertrophy. 2, 5
Even children with small tonsils may have significant OSA if adenoid hypertrophy is present, and conversely, children with large tonsils but minimal symptoms may have less adenoid involvement—this is why polysomnography is recommended when there's discordance between examination findings and symptoms. 1
Clinical Implications
When to Suspect Each Structure
Adenoid-predominant obstruction typically presents with: mouth breathing, hyponasal speech, chronic nasal congestion, and recurrent sinusitis/otitis media. 6
Tonsillar-predominant obstruction is more visible on physical examination with Grade 3-4 tonsillar hypertrophy ("kissing tonsils"). 2
However, clinical examination and history alone cannot reliably differentiate which structure is more problematic—only 55% of children with suspected OSA based on clinical evaluation actually had OSA confirmed by polysomnography. 1
Important Caveats
Obesity is actually the strongest independent predictor of the number of respiratory events (r = 0.49, p < 0.01), not adenoid or tonsil size alone. 4
Recurrence of symptoms after surgery occurs in 26% of infants, suggesting that anatomical factors are not the only contributors to sleep disturbances. 3
Complete resolution of OSA after adenotonsillectomy occurs in only 60-80% of normal-weight children and 10-50% of obese children, indicating that removing both structures doesn't always solve the problem entirely. 2
Non-Surgical Considerations
Intranasal corticosteroids should be trialed for adenoidal hypertrophy before surgical intervention, particularly when allergy-mediated inflammation is suspected. 2, 6
Rapid palatal expansion can reduce both adenoid (16.8% average) and tonsil (38.5% average) volumes in children with narrow high arch palate, offering a non-surgical alternative. 7