Sleep-disordered breathing in overweight and obese children and adolescents: prevalence, characteristics and the role of fat distribution

Abstract

Aim: To determine the prevalence of sleep- disordered breathing in a clinical sample of overweight and obese children and adolescents and to examine the contribution of fat distribution.

Methods: We recruited consecutive subjects without chronic lung disease, neuromuscular disease, laryngomalacia, or any genetic or craniofacial syndrome. All underwent measurements of neck and waist circumference, waist-to-hip ratio, % fat mass and polysomnography. Obstructive sleep apnea (OSA): obstructive apnea index ≥ 1 or obstructive apnea hypopnea index (oAHI) ≥ 2; and further classified as mild (2≤oAHI<5) or as moderate-to-severe (oAHI ≥ 5). Central sleep apnea: central apneas/hypopneas & ≥ 10 sec. accompanied by ≥ 1 age-specific bradytachycardia and/or ≥ 1 desaturation below 89%. Subjects with desaturation ≤ 85% following central events of any duration were also diagnosed as central sleep apnea. Primary snoring: snoring detected by microphone and normal obstructive indices and saturation.

Results: 27 overweight and 64 obese subjects were included (40 boys; <age> = 11.2 (SD 2.6)). Among the obese children, 53% were normal, 11% primary snoring, 11% mild OSA, 8% moderate-to-severe OSA and 17% central sleep apnea. Half of central sleep apnea patients desaturated below 85%. Only enlarged tonsils were predictive of moderate-to-severe OSA. On the other hand, higher levels of abdominal obesity and fat mass were associated with central sleep apnea.

Conclusion: Sleep-disordered breathing was very common in this clinical sample of overweight children. OSA was not associated with abdominal obesity. On the contrary, higher levels of abdominal obesity and fat mass were associated with central sleep apnea.