Obstructive sleep apnea syndrome in children: Epidemiology, pathophysiology, diagnosis and sequelae

Abstract

The prevalence of pediatric obstructive sleep apnea syndrome (OSAS) is approximately 3% in children. Adenotonsillar hypertrophy is the most common cause of OSAS in children, and obesity, hypotonic neuromuscular diseases, and craniofacial anomalies are other major risk factors. Snoring is the most common presenting complaint in children with OSAS, but the clinical presentation varies according to age. Agitated sleep with frequent postural changes, excessive sweating, or abnormal sleep positions such as hyperextension of neck or abnormal prone position may suggest a sleep-disordered breathing. Night terror, sleepwalking, and enuresis are frequently associated, during slow-wave sleep, with sleep-disordered breathing. Excessive daytime sleepiness becomes apparent in older children, whereas hyperactivity or inattention is usually predominant in younger children. Morning headache and poor appetite may also be present. As the cortical arousal threshold is higher in children, arousals are not easily developed and their sleep architectures are usually more conserved than those of adults. Untreated OSAS in children may result in various problems such as cognitive deficits, attention deficit/hyperactivity disorder, poor academic achievement, and emotional instability. Mild pulmonary hypertension is not uncommon. Rarely, cardiovascular complications such as cor pulmonale, heart failure, and systemic hypertension may develop in untreated cases. Failure to thrive and delayed development are serious problems in younger children with OSAS. Diagnosis of pediatric OSAS should be based on snoring, relevant history of sleep disruption, findings of any narrow or collapsible portions of upper airway, and confirmed by polysomnography. Early diagnosis of pediatric OSAS is critical to prevent complications with appropriate interventions.

Keywords: Child; Epidemiology; Obstructive sleep apnea syndrome; Pathophysiology; Sequelae.

Fig. 1

Mallampati score. Class 1: full visibility of tonsils, uvula, and soft palate. Class 2: visibility of hard and soft palate, upper portion of tonsils, and uvula. Class 3: soft and hard palate and base of the uvula are visible. Class 4: only hard palate is visible. Higher scores are correlated with having OSAS.

Fig. 2

Neck lateral view. The enlarged adenoid and tonsils are easily noted in this film.

Fig. 3

Obstructive hypopnea (60-second PSG epoch) in REM sleep. The event (arrow) was initiated by diminished nasal pressure airflow (TPAF) accompanied by paradoxical respiration leading to arousal. This respiratory event was associated with a ≥50% decrease in the amplitude of the nasal pressure signal. Ocular movement is seen on the electrooculogram (LOC-M2, ROC-M1).