View clinical trials related to Obstructive Sleep Apnea.
Filter by:Sleep-disordered breathing (SDB) briefly means cessation of breathing during sleep at least 5 times per hour. SDB is a common disorder affecting 9 to 24% of the middle-aged and overall 4% of the middle-aged male population suffers from the Obstructive sleep apnea syndrome (OSA) i.e. Sleep-disordered breathing (SDB) with associated daytime sleepiness. Several major epidemiological studies have shown that SDB is not only an independent risk factor for hypertension but it is also strongly associated with heart failure and stroke. The mechanism for the linkage between SDB and cardiovascular consequences is not fully determined. Vascular endothelial growth factor (VEGF) is a soluble 34-46 kD angiogenic heparin-binding glycoprotein. This cytokine regulates multiple endothelial cell functions including vascular permeability and vascular tone and some data suggest that it may contribute to the atherosclerotic process. Recent studies have shown increased plasma and serum concentrations of Vascular endothelial growth factor (VEGF) in patients with OSA and there were correlations between VEGF concentrations and the severity of OSA, as indexed by the minimum oxygen saturation level and the frequency of the upper airway obstruction per hour of sleep. A recent non-randomized study with a small sample size has shown a significant decrease in Vascular endothelial growth factor (VEGF) concentrations in patients in whom nocturnal hypoxia improved after 1 year of nasal continuous positive airway pressure (CPAP) therapy. Despite robust evidence showing improvement of symptoms, cognitive function and quality of life in obstructive sleep apnea (OSA) patients treated with nasal CPAP, there are nevertheless conflicting data whether Continuous positive airway pressure (CPAP) can reduce daytime blood pressure (BP) in patients with OSA. Two randomized placebo controlled studies have shown reduction of 24-hr systolic and diastolic blood pressure (BP) in obstructive sleep apnea (OSA) patients after 1 month of nasal continuous positive airway pressure (CPAP) therapy while other investigators have shown no such benefit. This randomized, sham-placebo controlled study aims to assess 1) the effect of nasal continuous positive airway pressure (CPAP) over a period of 3 months on 24 hr blood pressure (BP); and 2) whether any change in BP and plasma Vascular endothelial growth factor (VEGF) is related to the baseline severity of obstructive sleep apnea (OSA) and continuous positive airway pressure (CPAP) compliance.
Obstructive sleep apnea syndrome is complicated by considerable cardiovascular morbidity and mortality, at least partly due to hypertension. Nocturnal hypoxia, hypercapnia and acidosis stimulate chemoreceptors and presumably increased secretion of vasoactive hormones which might be responsible for hypertension in these patients. The aim of this study is to measure the secretion of vasoactive hormones at night and to analyse the relationship between vasoactive hormones, oxygen saturation and the blood pressure at night.
This study is designed to determine the effect of continuous positive airway pressure (CPAP) or bi-level positive airway pressure (BiPAP) on heart rate variability (HRV) in patients with obstructive sleep apnea (OSA).
Patients with obstructive sleep apnoea (OSA) have repetitive episodes of partial or complete upper airway obstruction during sleep. This leads to sleep fragmentation and symptoms like excessive daytime sleepiness and impaired psychosocial well-being. More evidence now suggested OSA is associated with cardiovascular diseases like hypertension, myocardial infarction, pulmonary hypertension and stroke. The upper airway structure and function are altered in OSA. Some studies suggested that an increase in the levels of systemic biomarkers of inflammation and oxidative stress in patients with OSA. So far, there is only very limited data on non-invasive monitoring of inflammation involved in the upper airway of OSA patients. The inflammatory mechanisms involved in the upper airway may give some insights to the systemic effect, like cardiovascular complications, of OSA. Measurement of the constituents of exhaled breath and exhaled breath condensate (EBC) is a non-invasive method to assess the degree of inflammation of the airway. Exhaled nitric oxide (eNO) can be measured with the subject exhaling to a mouthpiece connected to a machine measuring real-time eNO level. With the subject exhaling to a cooling unit, EBC can be collected as liquid is formed as a result of condensation. This study will assess the eNO in exhaled breath, oxidative stress marker (8-isoprostane) and cellular inflammatory markers (eotaxin, monocyted derived chemokine, growth related oncogene- alpha, monocyte chemoattractant protein-1) in the EBC and blood of OSA patients before and after 1 night and 3 months of continuous positive airway pressure treatment.
This follow up study (>1 year) aims to compare the effects of lifestyle intervention and gastric by pass surgery on various comorbidities associated with morbid obesity.
This study will look at an alternative new pathway for diagnosis and treatment based on simple procedures in the patient’s own home compared with the current conventional laboratory based pathway. The purpose is to determine whether all patients with OSA require the more elaborate laboratory procedures, or whether a subgroup can be managed more simply.
The purpose of this study was to determine how effective a custom-made standard dental splint (activator) advancing the lower jaw forward is in treatment of obstructive sleep apnea, and further to find factors for identification of those patients likely to benefit from this treatment.
Obstructive sleep apnea (OSA) is a medical problem whose importance is increasing in recognition and awareness. OSA is associated with the development of hypertension and other cardiovascular diseases (1,2). OSA has pathophysiologic characteristics that are known to negatively impact immune function. Both sleep deprivation and hypoxia, hallmarks of OSA, impair immune responses (6,8,11). In addition, patients with OSA are frequently obese and obesity may be associated with increased chance of infections and immune impairment (14,15). Adipose cells are known to secrete cytokines and hormones that are involved in the immune response such as leptin, tumor necrosis factor alpha and interleukin-6 (16-19). Thus, it seems very likely that OSA may impact antigen-specific immune responses. Although it is known that characteristics of OSA impact immune function, it is not known what effects clinical OSA has on immunity. The central hypothesis of this application is that that patients with obstructive sleep apnea will have attenuated cell-mediated and humoral immune responses to influenza vaccine compared to matched control subjects. Our hypothesis has been formulated on the basis that patients with OSA are sleep deprived and experience repeated hypoxemia that negatively impact both humoral and cell-mediated immune responses.
The purpose of this study is to determine if the mandibular advancement by Herbst device is effective in the treatment of moderate obstructive sleep apnea patients.
In this study we will examine whether suture repair of the palate, or roof of mouth, has any effect on results of palate surgery performed for treatment of obstructive sleep apnea.