Study objectives: To assess the prevalence of sleep-disordered breathing in a nonselected group of children with Down syndrome and to determine significant predisposing factors for this condition.
Design: Prospective study.
Setting: Tertiary care university hospital in Madrid, Spain.
Patients: The study population included 108 consecutive children with Down syndrome (mean [SD] age, 7.9 [4.5] years; range, 1-18 years) independently of whether or not suggestive clinical features of sleep-disordered breathing were present.
Interventions: In addition to history, physical examination, and lateral radiographs of the nasopharynx, all participants underwent an overnight cardiorespiratory polygraphy at the hospital using a portable ambulatory device (Apnoescreen II plus). An apnea-hypopnea index of at least 3 was required for defining the presence of sleep-disordered breathing.
Results: The prevalence of sleep-disordered breathing was 54.6%, with a significantly higher prevalence in boys (64.7%) than in girls (38.5%) (P < .05). The group with sleep-disordered breathing was significantly younger (6.4 [3.9] years) than those with normal polysomnographic recordings (9.6 [4.6] years) (P < .001). In the multivariate analysis, age (less than 8 years old) (odds ratio [OR], 3.36; 95% confidence interval [CI], 1.40, 8.06); male sex (OR, 3.32; 95% CI, 1.32, 8.12); and tonsillar hyperplasia (OR, 5.24; 95% CI, 1.52, 19.03) were significantly associated with sleep-disordered breathing. Body mass index, adenoid hyperplasia, previous tonsillectomy or adenoidectomy, congenital heart disease, malocclusion, and macroglossia did not affect the prevalence of sleep-disordered breathing.
Conclusions: The prevalence of sleep-disordered breathing in children with Down syndrome is very high, particularly in boys. Tonsillar hyperplasia may play a role in the pathophysiology of sleep-disordered breathing in these patients. Adenoid hyperplasia, obesity, and congenital heart disease were not important risk factors for sleep-disordered breathing.