Sleep-disordered breathing and systemic inflammation in overweight children and adolescents.

Objective: To assess if the severity of sleep-disordered breathing (SDB) and mainly intermittent hypoxia is associated with increased peripheral leukocytes in overweight children and adolescents, controlling for adiposity and obesity-related metabolic abnormalities.
Methods: Consecutive subjects were recruited at a pediatric obesity clinic. All subjects underwent polysomnography and a fasting blood sample.
Results: In total, 95 subjects were included (<age> =11.1+/-2.6, 43 boys, body mass index, <BMI z-score>=2.3+/-0.5, 29 subjects were overweight and 66 obese). Total white blood cell count increased significantly by worsening of intermittent hypoxia. Total white blood cell count was correlated with the maximal degree of desaturation, independent of puberty, HOMA and HDL-cholesterol. Neutrophil levels were associated with the degree of desaturation, while controlling for puberty and HOMA.
Conclusion: This study supports the hypothesis of an independent interaction between intermittent hypoxia and nocturnal desaturation during sleep, and increased white blood cell and neutrophil levels in overweight and obese children and adolescents. This finding may contribute to the mechanisms linking SDB with increased cardiovascular morbidity.