Apnea in Children

Etiology

While the most frequent cause of apnea in infants is idiopathic, obstructive sleep apnea due to tonsil and adenoidal hypertrophy, often coexisting with obesity, is the most common cause in children. Other conditions that predispose individuals to obstructive sleep apnea (OSA) include:

• Craniofacial anomalies (Pierre Robin sequence, Beckwith-Wiedemann syndrome, Apert syndrome, Treacher Collins syndrome)
• Chronic nasal obstruction (severe septal deviation, allergic rhinitis, nasal polyps)
• Down syndrome
• Metabolic abnormalities (mucopolysaccharidosis)
• Infections (supraglottis, croup, bronchiolitis, pneumonia)
• Asthma attacks
• Foreign body in the airway 
• Congenital chest wall deformities.

Sickle cell anemia has been associated with OSA, but its mechanism is unclear. Central sleep apnea (CSA) accounts for less than 5% of pediatric sleep-disordered breathing and results from neurologic dysfunction affecting respiratory drive. Predominant central causes of apnea include Chiari malformation (the most common diagnosis in one series), central nervous system (CNS) infections, raised intracranial pressure (accidental or inflicted head trauma, hydrocephalus, tumors), toxin exposures (CNS depressants, carbon monoxide poisoning), and central idiopathic hypoventilation.[6]

Neuromuscular disorders (Guillain-Barré syndrome, Duchenne muscular dystrophy, Werdnig-Hoffman disease) often cause mixed apnea. Morbid obesity itself can cause hypoventilation (Pickwickian syndrome) and predispose to apnea. Laryngospasm can occur as a protective reflex during episodes of gastroesophageal reflux and should be suspected when episodes are associated with feeding.[7][8][9][10] In contrast, sleep-related hypoventilation presents with elevated carbon dioxide levels during sleep without discrete apneic events.[11]

Epidemiology

Epidemiological data on pediatric apnea remain limited, with particularly few studies focused on obstructive sleep apnea (OSA). The estimated prevalence of OSA in otherwise healthy children ranges from 1% to 3%, while obesity increases this risk by 4 to 5 times. OSA occurs more frequently in black children, with a 3.5-fold higher risk, and in Hispanic children compared to white children. The condition affects prepubertal males and females equally, but prevalence rises in males after puberty.[12] Peak incidence occurs between ages 2 and 8 years, corresponding with the period of adenotonsillar hypertrophy.[13][12]

Recent evidence suggests that OSA prevalence may be increasing among preschool-aged children. Studies conducted before 2014 reported prevalence rates between 3.3% and 9.4%, while studies published from 2016 to 2023 indicate higher rates ranging from 12.8% to 20.4%.[14] This upward trend likely reflects the growing childhood obesity epidemic, as children with obesity demonstrate a 45% prevalence of OSA compared to 9% among children with a healthy weight.[15]

Pathophysiology

Central apnea results from direct depression of the respiratory center, which reduces its efferent output that stimulates breathing. Neuromuscular disorders cause both central and obstructive apnea (impaired pharyngeal tone and paralysis of the respiratory muscles). The pathophysiology is multifactorial, with most children having contributions from multiple mechanisms rather than a single cause.[16][13] This complexity explains why some children have persistent OSA after adenotonsillectomy and why treatment often requires an interprofessional approach addressing both anatomical and functional abnormalities.

Pediatric OSA results from a complex interplay between anatomical narrowing of the upper airway and neuromuscular factors that lead to recurrent partial or complete upper airway obstruction during sleep.[17] The pathophysiology differs from adults in several important ways, with adenotonsillar hypertrophy playing a more dominant role in children. The primary sites of anatomic obstruction are at the nasal, palatal, and hypopharyngeal airway levels. In children, adenotonsillar hypertrophy is the predominant anatomical cause. 

Craniofacial abnormalities contribute significantly to airway narrowing, including narrowing or retropositioning of the maxilla and mandible, micrognathia, retrognathia, high-arched palate, and reduced maxillomandibular volume.[17] Obesity increasingly contributes to pediatric OSA through fat deposition in the lateral pharyngeal walls and tongue, with children with obesity having a 45% prevalence of OSA compared to 9% in children with a healthy weight.[15]

Upper airway stability depends on neuromuscular activation, arousal threshold, and ventilatory control.[18] During sleep, muscular hypotonia reduces upper airway dilator muscle tone, making the already narrowed airway more susceptible to collapse. Additional factors that increase upper airway resistance include chronic sinusitis and nasal stenosis, allergic rhinitis causing nasal mucosal swelling, macroglossia, and recurrent upper respiratory tract infections. 

History and Physical

Clinical History

All children should undergo screening for snoring during well-child visits, although history and physical examination alone demonstrate low sensitivity and specificity for diagnosing OSA. These methods cannot reliably differentiate primary snoring from OSA or determine disease severity.[19][17] Children with positive screening findings require comprehensive evaluation, including polysomnography, to establish a definitive diagnosis.

Key components of history include nighttime symptoms, eg, frequent snoring 3 or more nights per week, labored breathing, gasps, snorting noises, observed apneas, sleep enuresis—particularly secondary enuresis after 6 months of continence—sleeping in unusual positions, eg, seated or with neck hyperextended, restless sleep with frequent position changes, and cyanosis during sleep.[20] Daytime symptoms may include headaches upon awakening, excessive daytime sleepiness, attention-deficit/hyperactivity or learning problems, and behavioral issues, eg, irritability, impulsivity, or hyperactivity. Age-specific patterns show that children younger than 5 years more often exhibit nighttime symptoms, whereas children older than 5 more commonly present with daytime sleepiness, behavioral problems, learning difficulties, or morning headaches.

Apnea Risk Factors

Risk factors for OSA include obesity (45% OSA prevalence versus 9% in healthy weight children), craniofacial abnormalities, eg, micrognathia, retrognathia, or high-arched palate, genetic disorders including Down syndrome, Crouzon syndrome, Treacher Collins, Apert syndrome, Pierre Robin syndrome, and Beckwith-Wiedemann syndrome, neuromuscular disorders, cerebral palsy, allergic rhinitis, asthma, and exposure to tobacco smoke.

Children exhibiting typical symptoms or risk factors should be referred to a pediatric sleep specialist or otolaryngologist, with overnight polysomnography serving as the gold standard for diagnosis. Limited availability of pediatric sleep centers may necessitate alternative evaluation pathways, including direct referral to pediatric otolaryngology.[15][12]

Physical Examination Findings

Physical examination findings associated with apnea in children include growth parameters indicating underweight, overweight, or failure to thrive; assessment of the upper airway for tonsillar hypertrophy or adenoidal facies; craniofacial features, eg, micrognathia, retrognathia, or high-arched palate; and elevated blood pressure, which may suggest cardiovascular complications. Clinical assessment of tonsillar size using the Brodsky score provides limited predictive value for OSA presence or severity, underscoring the importance of objective testing.[17]

Evaluation

The performance of lab and imaging studies should be based on indications uncovered by the history and physical examination. If OSA is suspected, polysomnography is considered to be the gold standard for diagnosis and determination of severity. Lateral neck x-rays may show adenoidal hypertrophy or other abnormalities, but these are not diagnostic. Pulse oximetry when asleep and/or sleep questionnaires may be used to identify children when polysomnography is not feasible.[21][22][23][10]

Treatment / Management

Treatment of pediatric apnea requires a personalized approach that considers apnea type, underlying etiology, severity, and patient-specific risk factors. OSA affects 1% to 5% of children, with more than 95% of cases resulting from upper airway obstruction, while central sleep apnea accounts for less than 5% of cases. Management strategies differ significantly between these types and must be individualized according to clinical presentation and comorbidities.

Adenotonsillectomy

Adenotonsillectomy remains the first-line treatment for children with adenotonsillar hypertrophy and OSA.[24][25] Surgical intervention improves cardiac function, blood pressure, biomarkers of cardiovascular risk, and endothelial function, although outcomes vary across studies. Persistent OSA occurs in up to 40% of children after adenotonsillectomy, with particularly high rates in children with obesity (50%), baseline severe OSA, or complex medical conditions.[26](A1)

Medical Therapy

Medical therapy includes intranasal corticosteroids alone or combined with montelukast for mild OSA, defined as an apnea-hypopnea index of 1 to 5 events per hour, or when surgery is contraindicated. A 1- to 6-month trial with close follow-up can be considered in children older than 2 years with mild disease.[24] Weight loss interventions complement other therapies for overweight or obese children, and bariatric surgery, eg, sleeve gastrectomy or gastric bypass, has demonstrated significant improvement in OSA severity and remission of type 2 diabetes, dyslipidemia, and hypertension at 5-year follow-up.[24]

Positive Airway Pressure Therapy

Positive airway pressure therapy includes CPAP, which is recommended when adenotonsillectomy is not performed or when OSA persists postoperatively. CPAP is more effective than adenotonsillectomy in lowering blood pressure in hypertensive children. High-flow nasal cannula may serve as a bridge therapy for young children, particularly those younger than 2 years with persistent OSA after surgery or for those intolerant to positive airway pressure therapy.[27]

Differential Diagnosis

Differential diagnoses that should also be considered when evaluating apnea in children include:

• Aspiration syndromes
• Bacteremia
• Botulism
• Brief resolved unexplained events 
• Bronchiolitis
• Bronchopulmonary dysplasia
• Croup
• Congestive heart failure
• Laryngomalacia
• Munchausen syndrome

Complications

Pediatric apnea, particularly OSA, can lead to significant short- and long-term complications if left untreated. Recurrent upper airway obstruction and intermittent hypoxia contribute to cardiovascular consequences, including elevated blood pressure, endothelial dysfunction, and impaired cardiac function. Children with persistent OSA may also experience growth disturbances, behavioral problems, attention-deficit/hyperactivity symptoms, learning difficulties, and daytime sleepiness, all of which can affect school performance and quality of life. Severe or untreated cases may exacerbate comorbid conditions such as obesity, asthma, or neuromuscular disorders, further increasing the risk of morbidity.

Long-term complications extend to metabolic and neurocognitive outcomes. Obesity amplifies the severity of OSA and may perpetuate a cycle of worsening apnea and metabolic dysregulation, including insulin resistance and dyslipidemia. Central nervous system hypoxia during sleep can contribute to neurocognitive deficits, including impaired attention, memory, and executive function. Persistent OSA after adenotonsillectomy, particularly in children with obesity or complex medical conditions, increases the likelihood of ongoing cardiovascular and neurobehavioral complications. Early recognition, comprehensive evaluation, and individualized management are essential to prevent these adverse outcomes and optimize long-term health.