Active clinical trials for "Apnea"

Randomized trial to evaluate the performance of Bilevel vs. Servoventilation in patients with complex sleep apnea during continuous positive airway pressure (CPAP) treatment.

The investigators' overall goal is to compare the effect of CPAP treatment on intermediate cardiovascular risk measures in obese versus lean patients with obstructive sleep apnea (OSA). The overall hypothesis is that, adjusting for OSA severity and obtaining normative data from non-OSA subjects with comparable amounts of visceral adiposity, the two OSA groups will have comparable improvements in daytime sleepiness, but that the cardiovascular and metabolic improvements following CPAP therapy will be decreased in OSA patients with increased visceral adipose tissue. The investigators anticipate that, although there will be a greater absolute change in markers of sympathetic activity, inflammation and oxidative stress in obese compared to lean OSA patients following CPAP treatment, the levels will still be abnormally high in the obese patients resulting in the decreased improvements in insulin resistance, arterial blood pressure, and vascular health in obese versus lean OSA patients.

MAIN AIMS: to analyze the efficacy of nasal CPAP treatment in patients with ischemic first-ever stroke and Sleep Apnea Syndrome (SAS) in terms of: early neurological outcome, functional recovery, quality of life influence, stroke recurrence and survival. SECONDARY AIMS: to evaluate the feasibility of the treatment in this type of patients at short and long time. DESIGN: clinical randomized case-control study. PATIENTS: younger than 75 years with a First-Ever stroke with at least one of the following criteria: snoring, observed apnea, Hypertension or Ischemic Cardiopathy. MEASUREMENTS: protocol to define subtype stroke and parenchymatous and vascular location; sleep questionnaire (including Epworth Sleepiness Scale); Respiratory Polysomnography (RPSG). If RPSG shows an AHI > 20, with predominant obstructive events, patients will be randomized in a CONTROL GROUP (conventional treatment) and a TREATMENT GROUP (with Nasal CPAP). Follow up for both groups at 1, 3, 12 and 24 months will include: early neurological outcome, body mass index (BMI), blood pressure (BP), functional recovery (Barthel Index/Canadian Scale), quality of life (SF36), recurrences, vital status. Nasal CPAP titration will be performed by means of an automatic system (Autoset Portable ST). Compliance will be recorded. If a negative RPSG is obtained (AHI < 10) (NO SAS GROUP) or with AHI < 20 (mild SAS) the usual treatment and the same follow up protocol will be established. STATISTICS: the sample size is initially calculated in 10 patients for each group, considering this is part of a multicenter study including 8 centers. If no differences are found, depending on the statistical power the investigators will consider including more patients. The different groups will be compared for the analyzed variables with the corresponding tests.

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.

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.

The purpose of the study is to compare the effectiveness of soft palatal implants with placebo and continuous positive airway pressure treatment in obstructive sleep apnea.

The purpose of this study is to assess patient reported outcomes with armodafinil treatment in terms of improvement in sleepiness, satisfaction with treatment, impact on ability to engage in life activities (ie, daily or work and family and/or social activities), and effects on fatigue. Clinician ratings on patient response to armodafinil treatment will also be assessed.

The purpose of this study is to determine if a certain medication, alone or combined with another medication, will increase muscle activity in the upper airway in people who do and people who do not have sleep apnea. The medications being studied are paroxetine, a commonly used antidepressant, and 5 hydroxy-tryptophan (5HTP), which also can be used as a dietary supplement without a prescription. Because the effects of paroxetine in previous studies were not very large, we will also study it combined with 5HTP to see if the effect on the upper airway muscles is greater.

The purpose of this study is to determine the effectiveness of nasal continuous positive airway pressure (CPAP) therapy for the treatment of obstructive sleep apnea syndrome (OSAS).

The main goal of this French multicenter observational cohort study is to prospectively collect data assessing the impact of the Adaptative Servo-Ventilation treatment on the quality of sleep of patients with central or combined sleep apnea syndrome (SAS) out of Heart Failure (HF) with altered ejection fraction, with a predominant central SAS.