Glycated hemoglobin and sleep apnea syndrome in children: beyond the apnea-hypopnea index.

PURPOSE: Snoring and obstructive sleep apnea syndrome (OSA) are frequent conditions in pediatrics. Glycated hemoglobin (HbA1C) is a useful homeostatic biomarker of glycemia and may reflect alterations deriving from sleep breathing disorders. The aim of this study was to relate the severity of OSA with blood HbA1C levels in children. METHODS: A descriptive observational study in snoring patients was performed. All patients underwent a sleep study and classified either as simple snorers (apnea-hypopnea index; AHI ≤ 1 episodies/h) or as OSA patients (AHI > 1 episodes/h). In the following morning, a blood glycemic profile (fasting glucose, insulin, HbA1C, and the HOMA index) was performed to every individual. RESULTS: A total of 48 patients were included. HbA1C levels were shown to be increased in the moderate OSA (AHI > 5 episodes/h) group (5.05 ± 0.25 vs. 5.24 ± 0.29%; p = 0.019). Significant correlations were found between HbA1C values and AHI (r = 0.345; p = 0.016) and also with oxygen desaturation index (r = 0.40; p = 0.005). Correlations remained significant after adjusting by age and body mass index. The AHI-associated change in HbA1C was 13.4% (p = 0.011). CONCLUSIONS: In the pediatric population, HbA1C is a biomarker associated with OSA severity, and this relationship is age- and obesity-independent. The fact that this association was observed in snoring patients could help the physician in the distinction between those patients affected with OSA and those with simple snoring. Therefore, HbA1C measurement could play a major role in the diagnosis and the management of the syndrome.

Comparing outcomes and costs between contingent and combined first-trimester screening strategies for Down's syndrome.

OBJECTIVE: To compare a contingent strategy with a combined strategy for prenatal detection of Down's syndrome (DS) in terms of cost, outcomes and safety. STUDY DESIGN: The contingent strategy was based on a simulation, removing measurement of the free beta subunit of human chorionic gonadotropin (free ßhCG) and calculating the DS risk retrospectively in 32,371 pregnant women who had been screened with the combined strategy in the first trimester. In the contingent strategy, a risk between 1:31 and 1:1000 in the first trimester indicated further testing in the second trimester (alpha-fetoprotein, inhibin A, unconjugated oestriol and free ßhCG). The cut-off risk values for the contingent and combined strategies in the first trimester were 1:30 and 1:250, respectively, and the cut-off risk value for integrated screening in the second trimester was 1:250. Costs were compared in terms of avoided DS births, and the ratio of loss of healthy fetuses following invasive procedures per avoided DS birth was calculated. RESULTS: The combined strategy had sensitivity of 40/44 (90.9%) and a false-positive rate of 2.8%. Corresponding values for the contingent strategy were 39/44 (88.6%) and 1.3%, respectively. Only 11% of pregnant women required tests in the second trimester, and the approximate cost reduction for each avoided DS birth was 5000€. The ratio of lost healthy fetuses following invasive procedures per avoided DS birth improved by up to 0.65. CONCLUSION: The contingent strategy has similar effectiveness to the combined strategy, but has lower costs and fewer invasive procedures.