Metabolic consequences of snoring in adolescents and younger adults: a population study in Chile.

STUDY OBJECTIVES: To investigate the potential association between snoring and other symptoms indicative of sleep-disordered breathing and metabolic syndrome (MetS) in Hispanic adolescents and younger adults using a large population-based survey. METHODS: Sleep-related information, anthropometric measurements and fasting blood samples markers of MetS were obtained from subjects aged 15-40 years collected through the 2nd Chilean Health Survey. Regression models were constructed to evaluate the associations of snoring with MetS, hypertension and serum cholesterol levels. The modulating effect of sleep duration was accounted for in the models. RESULTS: A total of 2147 subjects (42% males, mean age 27.9±7.6 years) were included. Snoring and short sleep duration were present in 43.5 and 25% of the entire population, respectively. MetS was detected in 19.5% of the subjects. In the adjusted regression model, the odds of MetS among snoring subjects were 2.13 times higher (95% confidence interval (CI): 1.52-2.99; P<0.01), and 1.53-fold higher odds of elevated cholesterol also emerged (95% CI: 1.12-2.10; P<0.01). However, the odds of hypertension were not increased by the presence of snoring after adjusting for confounders. In addition, snoring was associated with an increase of 7.26 and 6.56 mg dl-1 for total and low-density lipoprotein cholesterol, respectively, even after adjusting for age, sex and body mass index. Short sleep duration was associated with a small albeit significant risk increase for high systolic blood pressure. CONCLUSIONS: In this large population-based sample of young Hispanic adults and adolescents, snoring, but not sleep duration, emerged as an independent risk factor for dyslipidemia and MetS, but not for hypertension.

Urinary leukotriene excretion profile in children with exercise-induced asthma compared with controls: a preliminary study.

BACKGROUND: Leukotrienes are among the most important mediators associated with inflammatory responses in patients with exercise induced asthma (EIA). The aim of this study was to investigate the impact of exercise on the urinary leukotriene profile. Hence, we compared post exercise changes of urinary leukotriene E4 (LTE4) concentration between children with EIA and healthy controls. METHODS: Ten children with EIA and 15 controls were enrolled. Both groups underwent a standardised exercise challenge test (ECT). LTE4 concentration was measured in urine samples obtained pre and post ECT, using enzyme immunoassay and adjusted by urinary creatinine concentrations. RESULTS: Median (minimum-maximum) pre ECT concentration of LTE4 was 17.82 (7.58-90.23 pg/ml) in EIA and 17.24 (4.64-64.02 pg/ml) in controls, p=0.86. LTE4 concentration post ECT were 23.37 (4.02-93.00 pg/ml) in EIA and 11.74 (0.13-25.09 pg/ml) in controls, p=0.02. Changes of LTE4 concentration post ECT were 2.54 (-31.98 to 43.31 pg/ml) in cases and -13.53 (-46.00 to 11.02 pg/ml) in controls, p=0.03. There was no significant correlation between basal predicted FEV(1) [%] and changes in LTE4 concentration in cases (i.e., r(s)=0.14) nor controls (i.e., r(s)=0.12). There was a tendency towards more pronounced changes in LTE4 concentration post ECT in children with moderate/mild persistent asthma compared to those with mild but intermittent asthma. CONCLUSIONS: Children with EIA had significantly higher changes of urinary LTE4 concentrations post ECT compared to healthy controls. Urinary measurement of LTE4 may be an interesting and non-invasive option to assess control of EIA in children.

El buen control del asma: ¿previene la remodelación? / Good asthma control: prevent the airway remodeling?

La remodelación de la vía aérea es un proceso continuo de cambio caracterizado principalmente por el engrosamiento de la membrana que sostiene la mucosa respiratoria. Diversas moléculas y agentes han sido descritos como responsables de ello. En el presente artículo se desarrolla el concepto inflamación y su relación con el fenómeno de remodelación en asma, describiendo los grupos de riesgo que existen, el rol de las diversas interleukinas descritas, el rol de la edad de inicio, y finalmente las consecuencias de la introducción precoz de esteroides inhalados en niños. Si bien existen muchos aspectos claros, aún queda mucho por responder.

Relevance of the pH probe in sleep study analysis in infants.

BACKGROUND: To establish the relationship between sleep apnoea and gastro-oesophageal reflux in infants and describe the clinical, demographic and pHmetric profile and the characteristic of the sleep polysomnography with a pH probe. METHODS: A total of 102 consecutive patients were evaluated. Parents were requested to fill out a questionnaire about symptoms and previous therapy. Gastro-oesophageal reflux was considered abnormal when the percentage of time with pH less than 4 was higher than 4% of total sleep time. RESULTS: A total of 102 infants were enrolled, 53% males. Seventy-four per cent of the infants were full-term babies. At the moment of the polysomnography, the mean age of the sample was 2.6 months. Suspicion of apnoea was the most common clinical diagnosis prior to the study. Only two infants have abnormal electroencephalogram. Mild gastro-oesophageal reflux was seen in 37 (36%) infants, while 22 (21.5%) did not have any reflux episode, and the remaining 43 (42%) infants had reflux index in the pathologic range. Only one patient had an unequivocal temporal relationship between acid oesophageal reflux and respiratory pause with oxygen desaturation. DISCUSSION: Infants with history of apnoea or acute life threatening event frequently had gastro-oesophageal reflux episodes which did not correlated with respiratory events, suggesting that gastro-oesophageal reflux and apnoea often occur in the same infant as two separate events.

Alteraciones polisomnográficas en lactantes con reflujo gastroesofágico / Polysomnographic abnormalities in infants with gastroesophageal reflux

BACKGROUND: Infant apnea is a common problem that conveys significant burden to families and physicians. Its temporal relationship with gastroesophageal reflux (GER) is controversial. AIM: To establish whether infants with GER of different magnitude have a higher incidence of respiratory events than children without GER. PATIENTS AND METHODS: 146 consecutive patients were evaluated with polisomnography (PSG) and with an esophageal pH probe. Those infants without GER episodes or with an esophageal pH below 4.0 in less than 5 per cent of total sleep time were considered as physiologic GER (Group I), between 5-10 per cent as mild GER (Group II), and over 10 per cent as severe GER (Group III). These groups were evaluated for demographic and polysomnographic characteristics. RESULTS: There were no differences in the demographic and global PSG characteristics neither in oxymetry, heart rate or electroencephalographic abnormalities. Group III infants had a higher percentage of active sleep compared to infants of Group I (p < 0.05) and higher incidence of central pauses and apneas compared to infants of Group I (p < 0.05). CONCLUSIONS: The presence of severe GER may modify the sleep pattern in infants, increasing the percentage of active sleep. The presence of central pauses and apneas in infants with severe GER suggest an association between the inmaturity of the respiratory centers and the adaptation of the anti-reflux mechanisms.