Upper airway abnormalities increase the risk of pediatric morbidity in infants. A multidisciplinary approach to obstructive sleep apnea syndrome (OSAS) poses challenges to clinical practice. The incidence and causes of OSA are poorly studied in children under 2 years of age. To fill this gap, we performed this retrospective observational study to determine the causes of obstructive sleep apnea (OSA) in children admitted to our hospital between January 2016 and February 2018, after a brief unexplained event (BRUE) or for OSA. We reviewed the medical charts of 82 patients (39 males; BRUE n = 48; OSAS n = 34) and divided them into two age groups: < 1 year old (1-12 months; n = 59) and >1 year old (>12-24 months; n = 23). Assessment included nap polysomnography, multichannel intraluminal impedance-pH, and nasopharyngoscopy. Sleep disordered breathing was comparable between the two groups. Omega-shaped epiglottis, laryngomalacia, and nasal septum deviation were more frequent in the younger group, and nasal congestion in older group. Tonsillar and adenoidal hypertrophy was more frequent in the older group, while laryngomalacia and gastroesophageal reflux was more frequent in the younger group. Tonsil and adenoid size were associated with grade of apnea-hypopnea index severity in the older group, and laryngomalacia and gastroesophageal reflux in the younger group. The main causes of respiratory sleep disorders differ in children before or after age 1 year. Our findings have potential clinical utility for assessing the pathophysiology of obstructive sleep disordered breathing in patients less than 2 years old.
Keywords: brief resolved unexplained event; gastro-esophageal reflux; infants; laryngomalacia; obstructive sleep disordered breathing; polysomnography.