Although adenotonsillectomy improves SDB, it has variable effects on inflammatory and metabolic markers or blood pressure.

A positive correlation of severity of sleep-disordered breathing with morning fasting insulin levels, which is independent of obesity, was reported in adults and obese children. We hypothesized that both severity of sleep-disordered breathing and relative body mass index predict fasting insulin and homeostasis model assessment (HOMA) index values in nonobese children with habitual snoring. One hundred and ten subjects with habitual snoring (median age, 6 years; range, 2-13 years) underwent polysomnography and measurement of morning fasting insulin and glucose levels. The HOMA index was calculated. Thirty children had an apnea-hypopnea index (AHI) >/= 5 episodes/hr (median, 7.8 episodes/hr; range, 5-42.3 episodes/hr), and 80 subjects had an AHI < 5 episodes/hr (median, 1.9 episodes/hr; range, 0.2-4.9 episodes/hr). Insulin and HOMA index values were similar in children with AHI >/= 5 episodes/hr (median insulin, 4.9 mU/l; range, 1.66-19.9 mU/l; and median HOMA, 1; range, 0.36-4.95) and in subjects with AHI < 5 episodes/hr (median insulin, 5.8 mU/l; range, 0.74-41.1 mU/l; and median HOMA, 1.3; range, 0.13-9.72) (P > 0.05). No significant correlations were identified between insulin or HOMA index values and any polysomnography indices (P > 0.05). When multiple linear regression was carried out, relative body mass index was a significant predictor of log-transformed insulin levels or HOMA index values, but AHI and percentage of sleep time with saturation <95% were not. In conclusion, contrary to findings in adults and in obese children, severity of sleep-disordered breathing is not a significant predictor of fasting insulin or HOMA index values in nonobese children with habitual snoring.

Summary. Introduction: Adults with obstructive sleep apnea have increased sympathetic activity. It was hypothesized that in children with symptoms of obstructive sleep-disordered breathing (SDB), morning urine levels of catecholamines correlate with severity of nocturnal hypoxemia. Methods: Children with snoring referred for polysomnography and controls without snoring were recruited. Morning urine norepinephrine, epinephrine, normetanephrine, and metanephrine levels were measured (ng/mg urine creatinine). Results: Twelve children (age 5.2 AE 2.3 years) with severe hypoxemia (oxygen saturation of hemoglobin-SpO 2 nadir 86%), 20 subjects (age 6.1 AE 2.1 years) with moderate hypoxemia (SpO 2 nadir 90% and >86%), 22 children (age 6.6 AE 1.5 years) with mild nocturnal hypoxemia (SpO 2 nadir >90%), and 10 controls (age 7.1 AE 2.8 years) were studied. Children with severe hypoxemia had significantly higher log-transformed norepinephrine levels (1.63 AE 0.29) compared to those with moderate hypoxemia (1.43 AE 0.22; P < 0.05) or compared to controls (1.39 AE 0.31; P < 0.05). In subjects with SDB, log-transformed oxygen desaturation of hemoglobin index or SpO 2 nadir predicted log-transformed norepinephrine levels after adjustment by age, gender and body mass index (r 2 ¼ 0.24; and r 2 ¼ 0.24, respectively; P < 0.01). Conclusions: Severity of nocturnal hypoxemia in children with intermittent upper airway obstruction during sleep correlates with morning urine levels of norepinephrine suggesting increased sympathetic tone.

The aim of this study was to identify contributors to IR and to develop a model for predicting glucose intolerance in nondiabetic hemodialysis patients. After a 2-h, 75-g oral glucose tolerance test (OGTT), 34 hemodialysis patients were divided into groups with normal (NGT) and impaired glucose tolerance (IGT). Indices of insulin sensitivity were derived from OGTT data. Measurements included liver and muscle fat infiltration and central adiposity by computed tomography scans, body composition by dual energy X-ray absorptiometer, sleep quality by full polysomnography, and functional capacity and quality of life (QoL) by a battery of exercise tests and questionnaires. Cut-off points, as well as sensitivity and specificity calculations were based on IR (insulin sensitivity index by Matsuda) using a receiver operator characteristics (ROC) curve analysis. Fifteen patients were assigned to the IGT, and 19 subjects to the NGT group. Intrahepatic fat content and visceral adiposity were significantly higher in the IGT group. IR indices strongly correlated with sleep disturbances, visceral adiposity, functional capacity, and QoL. Visceral adiposity, O 2 desaturation during sleep, intrahepatic fat content, and QoL score fitted into the model for predicting glucose intolerance. A ROC curve analysis identified an intrahepatic fat content of Ͼ3.97% (sensitivity, 100; specificity, 35.7) as the best cutoff point for predicting IR. Visceral and intrahepatic fat content, as well as QoL and sleep seemed to be involved at some point in the development of glucose intolerance in hemodialysis patients. Means of reducing fat depots in the liver and splachnic area might prove promising in combating IR and cardiovascular risk in hemodialysis patients.insulin sensitivity index by Matsuda; homeostasis assessment model of insulin resistance; functional capacity; oral glucose insulin sensitivity; quality of life; quantitative insulin-sensitivity check index

A 51-year-old-woman presented with chronic eosinophilia, a diffuse interstitial lung pattern on CT and splenomegaly with hypodense lesions. A diagnosis of sarcoidosis was determined from a lung biopsy. Hyperinfection with strongyloides following treatment with systemic steroids explains the presence of eosinophilia and splenic involvement.

Dr. Ng suggests three reasons that may explain the absence of correlation between morning fasting insulin levels, a surrogate measure of insulin resistance, and severity of sleep-disordered breathing that was described in our recently published study of nonobese children with snoring. 1 Findings of the previous report are in contrast to those of the investigation by de la Eva et al. 2 in obese children with obstructive sleep apnea. Our comments regarding the three reasons suggested by Dr. Ng are as follows.First, we were aware of the fact that children with snoring and apnea-hypopnea index (AHI) <5 episodes/hr were not normal. The purpose of comparing children with AHI ! 5 episodes/hr to those with AHI < 5 episodes/hr was to show that the higher the severity of sleepdisordered breathing the higher the level of fasting insulin. Our study 1 did not include controls without snoring as a comparison group.Second, in addition to the AHI index we attempted to correlate several other polysomnography variables with fasting insulin levels and with Homeostasis Model Assessment (HOMA) index values. These variables included respiratory movement/arousal index, oxygen desaturation of hemoglobin index, and percentage of sleep time with saturation less than 95%. Similar parameters were also used by de la Eva et al. 2 in their investigation of obese children. We did not find correlations of fasting insulin levels with sleep study indices 1 but de la Eva et al. 2 did identify significant associations. Although in our report end-tidal CO 2 was not measured, this variable was not a significant predictor of insulin levels in obese children. 2 Third, when AHI is log-transformed to approach a normal distribution there is still no correlation with insulin levels (r ¼ À0.07; P ¼ 0.48) or HOMA index (r ¼ À0.07; P ¼ 0.46). Log-transformed AHI is not a significant predictor of either insulin levels or HOMA index.Last but not least, a recent report by Tauman et al. 3 reproduced our findings indicating that obesity rather than severity of sleep-disordered breathing is the major determinant of insulin resistance in snoring children. No correlation was identified between AHI and insulinto-glucose ratio even in obese children. Hence, more studies from other pediatric sleep centers would greatly enhance our knowledge on the possible correlation between insulin resistance and severity of sleepdisordered breathing in childhood.