Prevalence of obstructive sleep apnea in asthmatic school-aged children

Abstract

Background: Obstructive sleep apnea (OSA) and asthma are inflammatory diseases of the upper and lower airway tract respectively. Coexisting OSA and asthma can potentially have a cumulative effect on morbidity and should be recognized and treated. Objectives: we aimed to determine the prevalence and the risk factors associated with OSA in Egyptian school-aged children with asthma. Methods: Sixty-one asthmatic children (51% females and 49% males) aged 6-16 years were enrolled whereas those with acute attack of asthma, congenital syndromes/facial deformities, epilepsy, bronchiectasis and cardiac disease were excluded. All children were subjected to asthma control test, Brouilette questionnaire, sleep clinical record score (SCR), and clinical examination (chest/oro-dental/nasal) followed by full-night polysomnogram. Children with apnea/hypopnea index (AHI)≥2 events/hour were considered as OSA. Results: 57.4% were uncontrolled asthma and 42.6% partially controlled with mean age of 10.6±2.5 years and BMI of 19.7±4.7kg/m2 (13% obese). Among them 75.4% had OSA (AHI 4.2±3.3/hr, average O2 saturation 96±1.2% and minimal 84±6.7%) whereas 31% were moderate to severe OSA (AHI≥5). SCR and Brouillette score failed to identify OSA among uncontrolled asthma children (diagnostic accuracy of 60% both, p>0.05). In multivariate regression analysis, female sex seemed to be protective against development of OSA (odd ratio 0.6) while obesity, tonsillar hypertrophy, Friedman palate position, and nasal obstruction were risk factors for OSA (odd ratio 2.1, 2.4, 2.9, 2.1 respectively). Conclusion: OSA is common comorbidity in uncontrolled asthmatic children that is difficult to be screening using known scores as SCR and Brouilette score.