he ApneaLink Plus is a sensitive screening tool for evaluation of suspected OSAS in obese pediatric patients aged 9-18 years. The specificity improves with increasing OAHI cutoffs. The device detects OSAS when tested in a sleep laboratory on obese adolescents referred for symptoms of sleep related breathing disorder.

Background Although sleep-related breathing disorder (SRBD) has been linked to insulin resistance in adults, this has not been as well established in children. We hypothesized that the severity of SRBD in adolescents was associated with metabolic impairment. Methods Polysomnography was performed on obese, Latino males referred for snoring. The frequently sampled intravenous glucose tolerance test (FSIVGTT) was used to assess glucose homeostasis. Total body dual-energy X-ray absorptiometry (DEXA) was used to quantify adiposity. Results 22 males (mean age 13.4±SD 2.1 years, BMI z-score 2.4±0.3, obstructive apnea hypopnea index (OAHI) 4.1±3.2) were studied. After correcting for age and adiposity in multiple regression models, Log frequency of desaturation (defined as ≥3% drop in oxygen saturation from baseline) negatively correlated with insulin sensitivity. Sleep efficiency was positively correlated with glucose effectiveness (SG-the capacity of glucose to mediate its own disposal). The Log total arousal index was positively correlated with Log homeostasis model assessment (HOMA-IR). Conclusions Sleep fragmentation and intermittent hypoxemia are associated with metabolic impairment in obese adolescent Latino males independent of age and adiposity. We speculate that SRBD potentiates the risk for development of metabolic syndrome and type 2 diabetes in the obese adolescent population.

Is there a correlation between the 6-min walk and aerobic fitness in children? We studied healthy and cystic fibrosis (CF) subjects age 8-20 years using the 6-min walk test, treadmill graded exercise stress test, and spirometry. Six-minute walk distance (6MWD) and the product of 6MWD and body weight (6MWORK) were related to aerobic capacity. Data were analyzed using Student's t-test and Pearson correlation. 13 healthy subjects [9 females, mean age 15.8 +/- 3.6 years, % predicted forced expiratory volume in one second (FEV(1)) 105 +/- 12%, 6MWD 557 +/- 73 m, peak oxygen uptake (V' O2 max) 41.4 +/- 7.2 ml/kg/min, and heart rate (HR) at V' O2 max 180 +/- 10] and 11 CF subjects (3 females, mean age 14.3 +/- 3.8 years, FEV(1) 67 +/- 25.9%, 6MWD 468 +/- 68 m, V' O2 max 27.0 +/- 8.1 ml/kg, and HR at V' O2 max 163 +/- 22] were studied. 6MWD correlates with V' O2 max in normal subjects (r = 0.59, P < 0.05) but not in CF subjects (r = 0.09, NS). 6MWORK correlates with V' O2 max in CF subjects (r = 0.65, P < 0.05) but not in normal subjects (r = 0.278, NS). We conclude that the 6MWD corresponds with aerobic fitness in normal pediatric subjects and 6MWORK corresponds with aerobic fitness in CF subjects. We speculate that 6MWORK is superior to 6MWD for assessment of aerobic fitness in children with CF.