Study objectives: Assess the prevalence based on clinically meaningful criteria (i.e., blood pressure) and identify risk factors of sleep disordered breathing (SDB) in a representative sample of elementary school children.
Design: A random sample of the local elementary school children (K-5) were assessed using a two-phased strategy. In phase I a brief questionnaire was completed by a parent of each child in local elementary schools (N = 5,740), with a response rate of 78.5%. In phase II, randomly selected children and their parent spent a night in our sleep laboratory (N = 700) with a response rate of 70.0%.
Setting: University sleep laboratory.
Participants: Children enrolled in local elementary schools.
Measurement & results: Each child was assessed with a full polysomnogram and completed a history/physical examination including an electrocardiogram, otolaryngology examination, and pulmonary evaluation. The prevalence of moderate SDB (apnea-hypopnea index > or = 5) was 1.2%. The independent risk factors included nasal abnormalities and minority associated only with mild (1 < AHI < 5) SDB and snoring and waist circumference associated with all levels of SDB. Tonsil size, based on visual inspection, was not an independent risk factor.
Conclusion: The prevalence of AHI > or = 5 was 1.2% in a representative sample of elementary school children. Risk factors for SDB included waist circumference, nasal abnormalities (e.g., chronic sinusitis/rhinitis), and minority. The strong linear relationship between waist circumference and BMI across all degrees of severity of SDB suggests that, as in adults, metabolic factors may be among the most important risk factors for SDB in children.