View clinical trials related to Obstructive Sleep Apnea Syndrome.
Filter by:Introduction The portable monitoring system (PMS) recording of cardiopulmonary parameters (level III of ASDA) has been validated in subjects with high probability of Obstructive Sleep Apnea (OSA) without comorbidities. However, there is not any study evaluating this system when OSA is associated with morbid obesity, so the validation of PMS will be very useful in order to properly work-up this highly risk population. Objective: To evaluate the accuracy of level III type of PMS - Stardust™" (STD), on patients with level II and III of obesity and high clinical suspicion of OSA. Methods:Participants with BMI > 35 kg/m2 and with suspicion of OSA will consecutively be selected from an Outpatients Sleep Clinic of UNIFESP. They will be randomized for the following order of recordings: 1) STD at home for 1 night 2) STD in the sleep lab simultaneous to PSG. AHI will be taken for subsequent analysis:a) AHI PSG b) AHI STD -lab and c) AHI STD- home.
The literature does not discuss if the fast oral appliance titration (30 days period) in Obstructive Sleep Apnea Syndrome (OSAS) treatment, may improve subjects quality of life in such brief period. Temporomandibular dysfunction-related (TMD) is one of the most important side effects observed in OSAS treatment with oral appliance. Since the effectiveness of mandibular exercises in the control of TMD pain has already been verified, it may play a fundamental role in the support of the fast oral appliance titration.
Obstructive Sleep Apnea Syndrome (OSAS) is associated with elevated plasma levels of IL-6 and TNF-α, which cannot be accounted for by obesity (Vgontzas et al Sleep Med Rev 2005;9:211-24, Ciftci et al Cytokine 2004;28:87-91]. Obstructive apneas-hypopneas are accompanied by strenuous diaphragmatic contractions before the ensuing arousals and re-establishment of airway patency. We have shown that strenuous diaphragmatic contractions induced by resistive loading lead to elevated plasma levels of IL-6, TNF-α, and IL-1β (Vassi-lakopoulos et al AJRCCM 2002;166:1572-8) with concomitant up-regulation of the cytokines within the diaphragmatic myofibers (Vassilakopoulos et al AJRCCM 2004;170:154-61). OSAS patients exhibit frequent episodes of hypoxemia during the night. Loaded breathing is a form exercise for the respiratory muscles, and both acute and chronic hypoxia lead to an augmented plasma IL-6 response to exercise compared to normoxia (Lundby et al Eur J Appl Physiol 2004;91:88-93). In OSAS, monocytes have oxidative stress (Dyugovskaya et al AJRCCM 2002;165:934-9) and produce more cytokines (TNF-α) in vitro (Minoguchi et al Chest 204;126:1473-9). Hypothesis #1: plasma levels of IL-6 and TNF-α are increased during the night in OSAS patients secondary to the intermittent strenuous diaphragmatic contractions and the episodes of hypoxia-reoxygenation associated with the obstructive apneas-hypopneas. Hypothesis #2: monocytes from sleep apnea patients, exhibit augmented intracellular expression of IL-6 and TNF-α during the night. Hypothesis #3: Oxidative stress is a stimulus for cytokine upregulation in OSAS.
A pilot, prospective, comparative study. To include both male and female patients who have presented an ischaemic stroke (full stroke or TIA) or an ACS, 5 to 30 days prior to inclusion. The proposed study aims to investigate and analyse the differences in functional and structural arterial properties between the patients who presented an ischaemic stroke and those who presented ACS. The hypothesis is that the patients in both groups will present differences partly in terms of their "traditional" cardiovascular risk factors, but also in terms of their arterial properties. All of the confounding factors studied (cardiovascular risk factors, treatments) will be taken into account in order to explain the differences in the arterial properties found between the two groups. Furthermore, the prevalence of signs and symptoms in the two populations will be studied.
Obstructive Sleep Apnea Syndrome (OSAS) is a common condition that leads to daytime sleepiness and loss of vigilance and, in addition, increased risk of cardiovascular events. The most effective treatment consists in ventilation by mask with continuous positive airway pressure (CPAP), that prevents collapse of the upper airway. However the degree of collapsibility of the pharynx may vary in relation to position, sleep stage, or alcohol or sedative consumption. Thus, CPAP treatment (invented in 1981) has evolved with the development of more sophisticated equipment that permits adapted variations in pressure levels (autoCPAP) with the objective adjusted pressure to avoid airways obstruction with minimal pressure. Different models of autoCPAP function with different signals and event detection algorithms with different modes of reaction to events. These machines are marketed with CE certification, that guarantees electrical security, but there is to date, no requirement for pre-marketing clinical validation. Nonetheless inadequate treatment may leave patients at risk of accidents and cardiovascular events. These machines can be bench tested using test equipment that can measure with accuracy the response to simulated events, but the testing equipment cannot simulate the diversity of clinical situations, nor the residual level of microarousals that may persist. Thus these bench tests need to be supplemented by clinical studies. The investigators objective is to test the efficacy of these machines on residual sleep-related events during a one night autotitration polysomnography. We develop a prospective, multicentre, non randomised study with autotitration polysomnography only for one night. These clinical results will be compared with the results of bench tests in order to evaluate the pertinence of the bench tests and their eventual utility to simplify clinical evaluation. The perspective of developing a reliable testing protocol may eventually play a role in the certification of these machines.
Obstructive sleep apnea syndrome (OSAS) is a common disease, with a prevalence evaluated between 5 - 7% in the general population. OSAS is characterized by recurrent episodes of partial or complete upper airway obstruction during sleep, which are nearly systematically associated with a desaturation-reoxygenation sequence, an admitted detrimental stimulus for the cardiovascular system. It has now been demonstrated that OSAS per se is able to generate hypertension, atherosclerosis and autonomic dysfunction (high sympathic tone and increase in baseline heart rate), all conditions possibly interacting with ocular vascular regulation. OSAS has major consequences on the ocular level since it is associated with a higher frequency of optic neuropathies, such as glaucoma and nonarteritic ischemic optic neuropathy (NAION), both with functional severe prognosis. Most of vascular changes associated with OSAS have been studied at the level of macrovasculature. In terms of physiopathology, the main effects on the vascular system in OSAS are sympathetic hyperactivity, oxidative stress, development of endothelial dysfunction, systemic inflammation and metabolic alterations such as the appearance of insulin resistance. All these mechanisms can affect the microcirculation of the eye, especially the optic nerve and choroid. Our hypothesis is that the eye microvasculature is affected by OSAS, and these lesions may be detected via a reduced autoregulation of blood flow in humans. This project aims to demonstrate, quantify, and analyze the vascular modifications of the eye associated with OSAS trough a comparative clinical study on glaucoma patients and OSAS patients and matched healthy subjects for the regulation of the eye blood flow using confocal laser Doppler flowmetry (LDF). The regulation of the ocular blood flow will be assessed using several stimuli and measured using a new confocal LDF.
Patients with obstructive sleep apnea syndrome have permanent variations of their hemodynamic parameters during the night : heart rate, arterial blood pressure, cardiac output. This is due to the repetition of respiratory events (obstructive apnea and hypopnea) leading to frequent micro-arousals. These disorders have several consequences : hypertension, NO-dependent vasodilatation impairment, baroreceptor reflex impairment, insulin resistance and other cardiovascular impairments.
Individuals with obstructive sleep apnea syndrome (OSAS) are at high risk for cardiovascular morbidity and mortality. The effect of long-term nocturnal therapy with continuous positive airway pressure (CPAP) on daytime baroreflex sensitivity (BRS), a predictor of cardiac death, was investigated in OSAS patients.