Obstructive Sleep Apnea (OSA) in Children
Dr. Victor Jerome Ambrose is a pediatrician with special interest in pediatric sleep disorders. He underwent fellowship training in pediatric sleep and long term ventilation at Greater Ormond Street Hospital, London, UK. We interview him on sleep related issues in children.
1) What is obstructive sleep apnea (OSA) of childhood?
Obstructive sleep apnea syndrome (OSAS) is the extreme end of the spectrum of obstructive sleep disordered breathing in children (that includes three distinct phenotypes: Primary snoring (PS), Upper airway resistance syndrome (UARS), and OSAS). It is characterized by recurrent events of partial or complete upper airway obstruction during sleep resulting in disruption of normal ventilation, arousals, and disrupted sleep architecture
2) How prevalent is obstructive sleep apnea in childhood and what are the predominant causes?
The estimated prevalence of OSAS in childhood ranges from1.2% to 5.7%, it peaks between 2 and 8 years of age, and is usually associated with adenotonsillar hypertrophy. However, OSAS can occur in children of all ages, even those having normal sized tonsils and adenoids, or those having undergone adenotonsillectomy. As early as the neonatal period, underlying conditions such as craniofacial anomalies affecting upper airway structure, and neurological disorders affecting upper airway neuromotor tone may lead to airway obstruction during sleep. Later onset of symptoms, particularly when associated with obesity, maybe seen during school-age and adolescent years.
3) How is the diagnosis of OSA made?
Polysomnography, more often known as sleep study, is the gold standard for diagnosing OSA and other sleep disorders. However, when considering the sleep disordered breathing segment, sleep lab-based cardio-respiratory polygraphy has been known to be equally efficacious. The anterior rhinomanometry, and urinary biomarkers, which are yet to be used more commercially, also showed the best diagnostic test accuracy for diagnosing OSA in children when compared to polysomnography.
4) What polysomnographic criteria are applied in the diagnosis of OSA in children?
Polysomnographic criteria for scoring respiratory events for children were revised in 2013 in the American Academy of Sleep Medicine (AASM) Manual for the Scoring of Sleep and Associated Events. According to these guidelines, obstructive apnea lasts for at least two respiratory efforts with a greater than 90% fall in nasal pressure signal amplitude for greater than or equal to 90% of the entire respiratory event compared with pre-event baseline amplitude. Hypopneas must last the duration of two baseline breaths with a fall in the amplitude of the nasal pressure or alternative signal that is greater than or equal to 30% of baseline airflow and is associated with an arousal, an awakening, or at least 3% desaturation. The obstructive sleep apnea syndrome is defined as an obstructive AHI score of 2 or more events per hour or an obstructive apnea index (OAI) score of 1 or more events per hour.
5) How is childhood OSA managed?
· If a child is determined to have OSAS, has a clinical examination consistent with adenotonsillar hypertrophy, and does not have a contraindication to surgery, the clinician should recommend adenotonsillectomy (AT) as the first line of treatment. However, recent RCT study showed AT for OSAS in children resulted in clinically significant greater than expected weight gain, even in children overweight at baseline. In view of increase in adiposity in overweight children placing them at further risk for OSAS and the adverse consequences of obesity, it would be prudent to use clinical judgment to determine the benefits of adenotonsillectomy compared with other treatments in obese children with varying degrees of adenotonsillar hypertrophy
· Non-invasive ventilation with CPAP (continuous positive airway pressure) is considered an effective treatment of OSAS in children, if symptoms/signs or objective evidence of OSAS persists after adenotonsillectomy or if adenotonsillectomy is not performed.
· Nasal corticosteroids have been examined as an alternative to adenotonsillectomy in otherwise healthy children with mild to moderate OSA by exerting lympholytic action and effects on inflammation and upper airway edema. However, the clinical effects are small and because the long-term effect of this treatment is unknown, the clinician should continue to observe the patient for symptoms of recurrence and adverse effects of corticosteroids.
· Leukotriene receptor antagonist – Montelukast - was found to be clinically effective in reducing disease severity in children with mild OSA. In a recent double blind, placebo-controlled trial, montelukast effectively reduced polysomnographic findings, symptoms, and the size of the adenoidal tissue in children with non-severe OSA.
· Along with many other health-related benefits, achieving weight loss and increasing exercise seem to be beneficial for OSAS and should be recommended along with other interventions for OSAS in obese children and adolescents.
· Orthodontic therapy can be encouraged in pediatric OSAS, and an early approach may permanently modify nasal breathing and respiration, thereby preventing obstruction of the upper airway.
· Additional surgical procedures and tracheostomy are treatment options which are reserved for complex cases such as patients with craniofacial anomalies
· Katz ES, Moore RH, Rosen CL, Mitchell RB, Amin R, Arens R, et al. Growth after adenotonsillectomy for obstructive sleep apnea: an RCT. Pediatrics. 2014; 134: 282-289
· Goldbart AD, Greenberg-Dotan S, Tal A. Montelukast for children with obstructive sleep apnea: a double-blind, placebo-controlled study. Pediatrics. 2012; 130: e575-580
· Ersu RH (2015) Obstructive Sleep Apnea in Children: What are the Treatment Options? J Sleep Med Disord 2(4): 1028.