Search results for "intermittent hypoxia"

Plasma leptin and vascular endothelial growth factor (VEGF) in normal subjects at high altitude (5050 m)

2013

Context: High altitude (HA) is a model of severe hypoxia exposure in humans. We hypothesized that nocturnal hypoxemia or acute maximal exercise at HA might affect plasma leptin and VEGF levels. Objectives: Plasma leptin, VEGF and other metabolic variables were studied after nocturnal pulse oximetry and after maximal exercise in healthy lowlanders on the 3rd-4th day of stay in Lobuche (5050 m, HA) and after return to sea level (SL). Results: Leptin was similar at SL or HA in both pre- and post-exercise conditions. Pre-exercise VEGF at HA was lower, and cortisol was higher, than at SL, suggesting that nocturnal intermittent hypoxia associated with periodic breathing at HA might affect these v…

Diabetes mellitus prevalence and control in sleep-disordered breathing: The European Sleep Apnea Cohort (ESADA) study

2014

BACKGROUND: OSA is associated with an increased risk of cardiovascular morbidity. A driver of this is metabolic dysfunction and in particular type 2 diabetes mellitus (T2DM). Prior studies identifying a link between OSA and T2DM have excluded subjects with undiagnosed T2DM, and there is a lack of population-level data on the interaction between OSA and glycemic control among patients with diabetes. We assessed the relationship between OSA severity and T2DM prevalence and control in a large multinational population.METHODS: We performed a cross-sectional analysis of 6,616 participants in the European Sleep Apnea Cohort (ESADA) study, using multivariate regression analysis to assess T2DM prev…

Metabolic aspects of obstructive sleep apnoea syndrome.

2009

Insulin resistance is often associated with obstructive sleep apnoea syndrome (OSAS) and could contribute to cardiovascular risk in OSAS. Sleep loss and intermittent hypoxia could contribute to the pathogenesis of the metabolic alterations associated with obesity, a common feature of OSAS. The biology of the adipocyte is being increasingly studied, and it has been found that hypoxia negatively affects adipocyte function. In November 2007, the European Respiratory Society and two EU COST Actions (Cardiovascular risk in OSAS (B26) and Adipose tissue and the metabolic syndrome (BM0602)), held a Research Seminar in Du¨sseldorf, Germany, to discuss the following: 1) the effects of hypoxia on glu…

Tissue oxygenation in brain, muscle and fat in a rat model of sleep apnea: differential effect of obstructive apneas and intermittent hypoxia.

2011

Study Objectives: To test the hypotheses that the dynamic changes in brain oxygen partial pressure (PtO 2) in response to obstructive apneas or to intermittent hypoxia differ from those in other organs and that the changes in brain PtO 2 in response to obstructive apneas is a source of oxidative stress. Design: Prospective controlled animal study. Setting: University laboratory. Participants: 98 Sprague-Dawley rats. Interventions: Cerebral cortex, skeletal muscle, or visceral fat tissues were exposed in anesthetized animals subjected to either obstructive apneas or intermittent hypoxia (apneic and hypoxic events of 15 s each and 60 events/h) for 1 h. Measurements and Results: Arterial oxyge…

Sleep apnoea severity independently predicts glycaemic health in nondiabetic subjects: the ESADA study

2014

Abstract: Obstructive sleep apnoea (OSA) is associated with increased risk of dysglycaemia but the intimate link of these conditions with obesity makes discerning an independent relationship between them challenging. Glycosylated haemoglobin (HbA1c) levels predict adverse cardiovascular outcomes in nondiabetics but there is a lack of population-level data exploring the relationship of HbA1c with OSA. A cross-sectional analysis of 5294 participants in the multinational European Sleep Apnoea Cohort (European Sleep Apnoea Database) study was performed, assessing the relationship of OSA severity with HbA1c levels in nondiabetic subjects, with adjustment for confounding factors. HbA1c levels cor…

2020

Nasal continuous positive airway pressure (NCPAP) devices using variable (vf-) and continuous (cf-) flow or synchronized nasal intermittent positive pressure ventilation (s-NIPPV) are used to prevent or treat intermittent hypoxia (IH) in preterm infants. Results concerning which is most effective vary. We aimed to investigate the effect of s-NIPPV and vf-NCPAP compared to cf-NCPAP on the rate of IH episodes. Preterm infants with a gestational age of 24.9–29.7 weeks presenting with IH while being treated with cf-NCPAP were monitored for eight hours, then randomized to eight hours of treatment with vf-NCPAP or s-NIPPV. Data from 16 infants were analyzed. Due to an unexpectedly low sample size…

P1013 : Chronic intermittent hypoxia is associated with liver damage and atherosclerosis in patients with non-alcoholic fatty liver disease

2015

all the steatosis grades, except S2 vs S3. The diagnostic performances of CAP in quantifying each steatosis grade was: for S ≥1 AUC=0.813 (cutoff 260dB/m, Se = 64.84%, Sp =87.27%, PPV=80.8%, NPV=75%, +LR =5.09, −LR =0.40, DA=76.11%); for S ≥2 AUC=0.822 (cutoff 285dB/m, Se = 69.70%, Sp =85.12%, PPV=47.9%, NPV=93.5%, +LR =4.68, −LR =0.36, DA=82.08%); for S ≥3 AUC=0.838 (cutoff 294dB/m, Se =83.33%, Sp =82.54%, PPV=23.3%, NPV=98.7%, +LR =4.77, −LR =0.20, DA=81.59%). AUCs calculated between two steatosis grades only were: 0.772 (for S0 vs S1), 0.874 (S0 vs S2), 0.904 (S0 vs S3), 0.659 (S1 vs S2), 0.777 (S1 vs S3), and 0.665 (S2 vs S3) respectively. Conclusions: Maximal diagnostic accuracy could …

Obesity and intermittent hypoxia increase tumor growth in a mouse model of sleep apnea.

2012

Background: Intermittent hypoxia and obesity which are two pathological conditions commonly found in patients with obstructive sleep apnea (OSA), potentially enhance cancer progression. Objective: To investigate whether obesity and/or intermittent hypoxia (IH) mimicking OSA affect tumor growth. Methods: A subcutaneous melanoma was induced in 40 mice [22 obese (40–45 g) and 18 lean (20–25 g)] by injecting 106 B16F10 cells in the flank. Nineteen mice (10 obese/9 lean) were subjected to IH (6 h/day for 17 days). A group of 21 mice (12 obese/9 lean) were kept under normoxia. At day 17, tumors were excised, weighed and processed to quantify necrosis and endothelial expression of vascular endothe…

Nocturnal intermittent hypoxia predicts prevalent hypertension in the European Sleep Apnoea Database cohort study.

2014

Systemic hypertension is associated with obstructive sleep apnoea syndrome (OSAS) but the pathophysiological mechanisms are incompletely understood. A collaborative European network of 24 sleep centres established a European Sleep Apnoea Database to evaluate cardiovascular morbidity associated with OSAS.11 911 adults referred with suspected OSAS between March 2007 and September 2013 underwent overnight sleep studies, either cardiorespiratory polygraphy or polysomnography. We compared the predictive value of the apnoea–hypopnoea index (AHI) and 4% oxygen desaturation index (ODI) for prevalent hypertension, adjusting for relevant covariates including age, smoking, obesity, dyslipidaemia and d…

Lärm auf der Neugeborenen-Intensivstation: randomisierte Studie zum Einfluss eines Gehörschutzes auf intermittierende Hypoxien und Bradykardien

2015

Hintergrund: Atemregulationsstorungen Fruhgeborener, die mit Hypoxie und Bradykardie einhergehen, sind ein haufiges Problem mit unvollstandig verstandener Pathophysiologie. Unruhe des Kindes, z.T. durch Umgebungslarm ausgelost, ist moglicherweise ein Einflussfaktor. Wir wollten wissen, ob ein Gehorschutz die Haufigkeit von Hypoxien bei Fruhgeborenen mindestens halbiert. Patienten und Methoden: In einer randomisiert-kontrollierten Interventionsstudie mit Cross-Over Design wurde bei 31 Fruhgeborenen (14 mannlich; mittleres [min.-max.] Geburtsgewicht und Gestationsalter: 1 323 g [560–1 990] und 301/7 Wochen [255/7–330/7]) der Effekt eines Gehorschutzes auf die Haufigkeit von Sauerstoffentsatti…