SEARCH · PubMed Health

Results for “OSA”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41Linked to original sources

PubMedDate not supplied

The current status of autotitrating continuous positive airway pressure systems in the management of obstructive sleep apnea.

BACKGROUND: Autotitrating continuous positive airway pressure (APAP) devices have the potential to address some of the disadvantages of titration and treatment with conventional continuous positive airway pressure (CPAP). Information on the performance of APAP in clinical use is still comparatively limited. OBJECTIVE: To assess the status of APAP devices in the management of obstructive sleep apnea (OSA) by reviewing evidence of their efficacy, effectiveness and costs. METHODS: A systematic search of electronic databases and a review of selected comparative studies on the use of APAP in the diagnosis, titration and treatment of OSA was undertaken. Cost analysis using data applicable to the management of OSA in Edmonton, Alberta was performed. RESULTS: Thirty-three studies met the selection criteria: three on the use of APAP in diagnosing OSA; six on APAP for titration; 14 that considered short-term treatment outcomes; and 10 that addressed longer-term treatment of OSA. In most studies, patients suffering from cardiac, pulmonary and other medical conditions were excluded. Available data suggested some potential for the use of APAP in the diagnosis of OSA, but further validation is needed. In titration, estimated treatment pressures tended to be lower with APAP than with the manual titration of CPAP. Although lower treatment pressures were achieved with APAP, there was no significant difference in clinical outcome measures between APAP and CPAP. Estimates of costs suggested that APAP may provide savings in some scenarios. CONCLUSIONS: APAP shows promise in the management of OSA; however, given the exclusion of some categories of patients from trials of this technology, caution is still required in its use.

Continuous Positive Airway Pressure↗

PubMedDate not supplied

Insomnia subtypes and their relationships to daytime sleepiness in patients with obstructive sleep apnea.

BACKGROUND: Insomnia and obstructive sleep apnea syndrome (OSA) are the two most common sleep disorders. Studies showed that insomnia complaints were prevalent in OSA. Relatively little is known about the causes of insomnia in OSA and whether etiological factors differ for insomnia subtypes. We hypothesized that sleep onset problem was mainly due to hyperarousal and sleep maintenance difficulty was primarily related to sleep-disordered breathing. OBJECTIVES: To determine the prevalence of insomnia subtypes in OSA, compare subjects with sleep onset insomnia, sleep maintenance insomnia and no insomnia symptom, and study the relationship of insomnia subtypes to daytime sleepiness. METHODS: We analyzed intake questionnaires and polysomnography and Multiple Sleep Latency Test results of 157 OSA patients. RESULTS: Forty-two percent of the sample had at least one problematic insomnia symptom. The prevalence of sleep onset insomnia, sleep maintenance insomnia and insomnia with early awakening was 6, 26 and 19%, respectively. Patients with sleep onset insomnia had significantly lower apnea-hypopnea (AHI) and arousal indices. There were significant inverse relationships between sleep onset insomnia and measures of daytime sleepiness. On the contrary, subjects with repeated wakening had more severe subjective sleepiness. Results were similar in patients with AHI >or=5 or >or=15. CONCLUSIONS: Insomnia symptoms were common in OSA patients. Insomnia subtypes related differently to measures of daytime sleepiness. Our findings suggest that OSA patients with sleep onset insomnia may be in a state of hyperarousal. It is clinically relevant to examine insomnia subtypes, which may influence the treatment decision in sleep-disordered breathing.

Adult↗

PubMed2005

Deleterious effects of sleep-disordered breathing on the heart and vascular system.

Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing, affecting 5-15% of the population. It is characterized by intermittent episodes of partial or complete obstruction of the upper airway during sleep that disrupts normal ventilation and sleep architecture, and is typically associated with excessive daytime sleepiness, snoring, and witnessed apneas. Patients with obstructive sleep apnea present risk to the general public safety by causing 8-fold increase in vehicle accidents, and they may themselves also suffer from the physiologic consequences of OSA; these include hypertension, coronary artery disease, stroke, congestive heart failure, pulmonary hypertension, and cardiac arrhythmias. Of these possible cardiovascular consequences, the association between OSA and hypertension has been found to be the most convincing. Although the exact mechanism has not been understood, there is some evidence that OSA is associated with frequent apneas causing mechanical effects on intrathoracic pressure, cardiac function, and intermittent hypoxemia, which may in turn cause endothelial dysfunction and increase in sympathetic drive. Therapy with continuous positive airway pressure has been demonstrated to improve cardiopulmonary hemodynamics in patients with OSA and may reverse the endothelial cell dysfunction. Despite the availability of diagnostic measures and effective treatment, many patients with sleep-disordered breathing remain undiagnosed. Therefore, OSA continues to be a significant health risk both for affected individuals and for the general public. Awareness and timely initiation of an effective treatment may prevent potential deleterious cardiovascular effects of OSA.

Arrhythmias, Cardiac↗

PubMed2006

Association of the -1438G/A polymorphism of the 5-HT2A receptor gene with obstructive sleep apnea syndrome.

OBJECTIVE: Serotonergic neurons innervating motoneurons increase their firing rates in response to respiratory challenges, and long-term facilitation of respiratory activity in response to hypoxia is serotonin (5-HT) dependent. Polymorphism of the genes which code for 5-HT receptors may affect functions of the serotonergic system, and may be associated with obstructive sleep apnea syndrome (OSAS). The objective in this study was to assess the significance of T102C and -1438G/A polymorphisms of the 5-HT2A receptor gene in OSAS. METHODS: Fifty-five patients with OSAS and 102 healthy volun teers were included for genetic analyses of T102C and -1438G/A polymorphisms of the 5-HT2A receptor gene. RESULTS: For the T102C polymorphism, there was no significant difference between the patients and controls and both genders (p > 0.05). For the -1438G/A polymorphism, the A/A and G/A genotypes were overrepresented in the patients and controls, respectively (p = 0.045). In the control group, the genotypes of both genders were not significantly different (p > 0.05). In the patients, the A/A and G/A genotypes were overrepresented in males and females, respectively (p = 0.035). Concerning males, the A/A genotype was overrepresented in patients (p = 0.007). CONCLUSION: Serotonergic mechanisms appear to be related to OSAS. The T102C polymorphism of the 5-HT2A receptor gene is not associated with OSAS. However, the -1438G/A polymorphism is associated with OSAS occurrence, especially in male patients. This polymorphism may also be associated with different OSAS incidences of both genders.

Case-Control Studies↗

PubMed1992

Changes of circulating atrial natriuretic peptide and antidiuretic hormone in obstructive sleep apnea syndrome.

Patients with obstructive sleep apnea (OSA) syndrome are known to exhibit nocturnal natriuresis/diuresis. We studied plasma and urinary levels of atrial natriuretic peptide (ANP), a potent natriuretic hormone released from the heart, and plasma antidiuretic hormone (ADH) levels in patients with OSA during awake and sleeping periods, to compare with those of normal subjects. Seven patients with OSA and 6 normal subjects were studied. Arterial blood samples were drawn during the awake and the sleeping period, while in patients with OSA, blood samples were obtained during the apneic period. Urine samples were collected over two 12-hour periods (9 a.m.-9 p.m. and 9 p.m.-9 a.m.) In patients with OSA, plasma ANP as well as urinary ANP excretion increased during the apneic period compared with the awake period. There was a significant negative correlation between plasma levels of ANP and ADH in patients with OSA. On the other hand, normal subjects had no apparent differences in plasma and urinary ANP levels between the two periods. It is suggested that nocturnal increase in ANP and decrease in ADH are responsible for the nocturnal diuresis and natriuresis associated with OSA.

Adult↗

PubMed2003

Obstructive sleep apnea and the recurrence of atrial fibrillation.

BACKGROUND: We tested the hypothesis that patients with untreated obstructive sleep apnea (OSA) would be at increased risk for recurrence of atrial fibrillation (AF) after cardioversion. METHODS AND RESULTS: We prospectively obtained data on history, echocardiogram, ECG, body mass index, hypertension, diabetes, NYHA functional class, ejection fraction, left atrial appendage velocity, and medications in patients with AF/atrial flutter referred for DC cardioversion. Forty-three individuals were identified as having OSA on the basis of a previous sleep study. Data regarding the use of continuous positive airway pressure (CPAP) and recurrence of AF were obtained for 39 of these patients. Follow-up data were also obtained in 79 randomly selected postcardioversion patients (controls) who did not have any previous sleep study. Twenty-seven of the 39 OSA patients either were not receiving any CPAP therapy (n=25) or were using CPAP inappropriately (n=2). Recurrence of AF at 12 months in these 27 patients was 82%, higher than the 42% recurrence in the treated OSA group (n=12, P=0.013) and the 53% recurrence (n=79, P=0.009) in the 79 control patients. Of the 25 OSA patients who had not been treated at all, the nocturnal fall in oxygen saturation was greater (P=0.034) in those who had recurrence of AF (n=20) than in those without recurrence (n=5). CONCLUSIONS: Patients with untreated OSA have a higher recurrence of AF after cardioversion than patients without a polysomnographic diagnosis of sleep apnea. Appropriate treatment with CPAP in OSA patients is associated with lower recurrence of AF.

Aged↗

PubMed2005

Obstructive sleep apnea syndrome affects left ventricular diastolic function: effects of nasal continuous positive airway pressure in men.

BACKGROUND: The purpose of this study was to determine the role of obstructive sleep apnea syndrome (OSAS) as an independent risk factor for the development of left ventricular diastolic abnormalities. Moreover, we tested the hypothesis that nasal continuous positive airway pressure (nCPAP) improves such alterations in OSAS patients by eliminating apneic events. METHODS AND RESULTS: In this prospective, randomized, placebo-controlled, double-blind crossover study, 27 consecutive newly diagnosed middle-aged OSAS men with neither controllable factors nor conditions affecting left ventricular diastolic function and 15 healthy control subjects were selected. OSAS patients were randomized to 12 weeks on sham nCPAP and 12 weeks on effective nCPAP application. Echocardiographic parameters, blood pressure recordings, and urinary catecholamine levels were obtained at baseline and after both treatment modalities. At baseline, an abnormal left ventricular filling pattern was present in 15 of the 27 OSAS patients and only in 3 of the 15 control subjects (P=0.020). Impaired relaxation was by far the most common abnormal pattern in both groups (11 and 3 patients, respectively). In OSAS patients, 12 weeks on effective nCPAP induced a significant increase in E/A ratio (P<0.01), as well as reductions in mitral deceleration (P<0.01) and isovolumic relaxation (P<0.05) times. CONCLUSIONS: OSAS can affect left ventricular diastolic function independently of other possible factors. Chronic application of nCPAP could avoid the progression of diastolic abnormalities, and indeed, it might reverse these alterations, at least in the initial stages before severe structural changes can be developed.

Adult↗

PubMed1996

Upper airway shape: Is it important in the pathogenesis of obstructive sleep apnea?

It is widely accepted that the size of the airway and the level of upper airway muscle activity contribute to the pathogenesis of obstructive sleep apnea (OSA). However, some individuals with normal airway size and apparently normal upper airway muscle activity nonetheless develop OSA. Recent data and analysis suggest that airway shape may also contribute to the development of OSA; patients with OSA tend to have elliptical airways, with the long axis of the ellipse oriented along the anteroposterior axis, and this orientation may adversely affect upper airway muscle function. By incorporating airway shape, airway size, and upper airway muscle activity into a unified hypothesis of the pathogenesis of OSA, it may be possible to reconcile discrepant anatomic and electromyographic findings in patients with OSA, to explain the difficulty of selecting appropriate surgical therapy for patients with OSA using currently available diagnostic tools, and to understand the often disappointing response to upper airway surgery in these patients.

Electromyography↗

PubMed1998

Instability of ventilatory control in patients with obstructive sleep apnea.

Because of the oscillatory pattern of upper airway resistance and breathing during sleep in patients with obstructive sleep apnea (OSA), we hypothesized that OSA patients have an underlying instability of ventilatory drive to inspiratory muscles. To assess the stability of ventilatory drive in OSA patients and controls, we used the pseudorandom binary stimulation (PRBS) test and examined the closed- and open-loop responses to hyperoxic hypercapnia. The closed-loop response is produced by interactions of dynamic gain in controller, plant, and ventilatory feedback. The open-loop response reflects controller dynamic gain or frequency-dependent chemosensitivity. As compared with 16 nonapneic, nonobese control subjects, a group of nine obese OSA patients had a higher peak response and a more rapid and irregular recovery phase of the closed-loop CO2 response in the PRBS test. The two groups had similar open-loop responses in the PRBS test, suggesting that central dynamic CO2 chemosensitivity was not abnormal in OSA. We conclude that the differences between OSA patients and controls in the closed-loop response in the PRBS test are not due to differences in dynamic controller gain, but are related to differences in dynamic plant gain and/or negative ventilatory feedback. In addition to OSA, obesity may affect these variables and may have been responsible for our findings.

Adult↗

PubMed1999

Acute and chronic effects of airway obstruction on canine left ventricular performance.

We used a canine model of chronic obstructive sleep apnea (OSA) to examine the effects of intermittent airway occlusion during sleep on left ventricular (LV) performance. Studies were performed in four dogs. The effects of acute airway occlusion on LV pressure and volume (on a background of chronic OSA) were determined with an impedance catheter and a high fidelity manometer. In conscious animals (n = 3), experiencing spontaneous episodes of sleep, acute airway occlusion caused significant increases in LV transmural systolic pressure that were associated with increased end-systolic volume and reduced stroke volume. To determine the effects of chronic OSA on baseline LV function, two-dimensional echocardiograms were performed in conscious animals (n = 4) during unobstructed breathing before and after a 1- to 3-mo period of OSA. During chronic OSA, there was a significant decrease in LV ejection fraction as a result of increases in end-systolic volume. We conclude that in chronic OSA acute airway occlusion during sleep is associated with increases in LV afterload and decreases in fractional shortening. Chronic OSA also leads to sustained decreases in LV systolic performance that could be caused by the development of systemic hypertension and/or transient increases in LV afterload during episodes of airway obstruction.

Airway Obstruction↗

PubMed2000

Enhanced release of superoxide from polymorphonuclear neutrophils in obstructive sleep apnea. Impact of continuous positive airway pressure therapy.

Obstructive sleep apnea (OSA) is associated with increased cardiovascular morbidity and mortality. Free oxygen radicals have been implicated in the pathogenesis of cardiovascular disorders. Therefore, we aimed to test the hypothesis that increased oxidative stress constitutes one underlying mechanism for the connection between OSA and cardiovascular disease. In 18 patients with OSA the release of superoxide from polymorphonuclear neutrophils was determined after stimulation with the bacterial tripeptide formylmethionylleucylphenylalanine (fMLP) and the calcium ionophore A23. Superoxide production was measured as superoxide dismutase-inhibitable reduction of cytochrome c. Blood samples were obtained before and after two nights of CPAP therapy and after 4.8 +/- 0.6 mo of follow-up. Ten healthy young volunteers and 10 lung cancer patients without OSA but a similar spectrum of comorbidity served as controls. Before CPAP, neutrophil superoxide generation was markedly enhanced in OSA when compared with both control groups. Effective CPAP therapy led to a rapid and long-lasting decrease of superoxide release in OSA. In conclusion, OSA is linked with a "priming" of neutrophils for enhanced respiratory burst. The increased superoxide generation, which might have major impact on the development of cardiovascular disorders, is virtually fully reversed by effective CPAP therapy.

Adult↗

PubMed2001

Upper airway sensation in snoring and obstructive sleep apnea.

Previous studies indicate that upper airway (UA) sensory receptors play a role in the maintenance of UA patency and contribute to arousal in response to airway occlusion. An impairment of UA sensory function could therefore predispose to UA obstruction during sleep. We hypothesized that UA sensation is impaired in obstructive sleep apnea (OSA), and that sensation improves after treatment with nasal continuous positive airway pressure (CPAP). We measured two-point discrimination (2PD) and vibratory sensation thresholds (VT) in 37 patients with OSA (mean [+/- SE] apnea- hypopnea index [AHI] = 39 +/- 5 events/h), 12 nonapneic snorers (SN), and 15 control subjects (CL). Sensory thresholds were determined in the UA and on the lip and hand as control sites. Both 2PD and VT were similar among the three groups at the lip and hand sites but were significantly reduced in the UA of OSA and SN subjects versus CL (p < 0.05). Values for 2PD and VT in the UA of OSA versus SN were not significantly different. Sensory measures were repeated after 6 mo in 23 OSA patients treated with CPAP as well as in 18 untreated patients. Thresholds for 2PD and VT at control sites remained identical in both groups, as did 2PD for the UA. However, VT in the UA showed a significant improvement in treated (4.4 +/- 0.2 pre-CPAP versus 3.8 +/- 0.2 mm post-CPAP, p < 0.05) but not untreated patients. These findings indicate the presence of a selective impairment in the detection of mechanical stimuli in the UA of patients with OSA and SN, which is partially reversible after treatment with nasal CPAP in patients with OSA.

Adult↗

PubMed1991

Why don't all heavy snorers have obstructive sleep apnea?

Patients with obstructive sleep apnea (OSA) and heavy snorers without apnea both show intrathoracic suction pressures during sleep that exceed their static upper airway closing pressures. Complete airway occlusion, however, occurs only in the former patient group. We hypothesized that the kinetic properties of the airflow would be different in these two types of patients because of differences in upper airway morphology. The pharyngeal computed tomography (CT) was used to measure the cross-sectional areas of the upper airways in 15 patients with OSA, 25 nonapneic heavy snorers, and 14 control subjects while they were awake. Nocturnal breathing was monitored with the static charge-sensitive bed (SCSB). The patients with OSA had a narrower airspace at the velopharyngeal (VP) level than the controls (p less than 0.01); the nonapneic snorers did not differ from the other groups. At the tongue base (TB) and the hyoid bone (HB) levels there was no difference between the OSA and the control groups, but the nonapneic snorers had narrower airways at both of these levels compared with control subjects (p less than 0.01) and at the hyoid bone level compared with the OSA group (p less than 0.05). The VP/HB ratio was the parameter that best distinguished the patients with OSA from the nonapneic snorers (lower in the OSA group, p less than 0.001). We suggest that airway collapse during sleep is favored by a narrow velopharynx associated with large hypopharynx. Some heavy snorers may not have an oropharyngeal collapse because the peak inspiratory suction pressure could already be damped down at the level of the relatively narrow hypopharyngeal airways.

Airway Resistance↗

PubMed2002

Brain morphology associated with obstructive sleep apnea.

Obstructive sleep apnea (OSA) is characterized by repeated occurrences of hypoxic, hypercapnic, and transient blood pressure elevation episodes that may damage or alter neural structures. Underdeveloped structures or pre-existing damage in brain areas may also contribute to the genesis of the syndrome. Brain morphology in 21 patients with OSA and in 21 control subjects was assessed using high-resolution T1-weighted magnetic resonance imaging. Three-dimensional brain images were obtained with voxels of approximately 1 mm3. Images were spatially normalized and segmented into gray matter, white matter, and cerebrospinal fluid. For each segment, regional volumetric differences were determined relative to age, handedness, and group (patients with OSA versus control subjects), using voxel-based morphometry, with OSA effects weighted by disease severity. A significant age effect on total gray matter was found in control subjects but not in patients with OSA. Diminished regional and often unilateral gray matter loss was apparent in multiple sites of the brain in patients with OSA, including the frontal and parietal cortex, temporal lobe, anterior cingulate, hippocampus, and cerebellum. Unilateral loss in well-perfused structures suggests onset of neural deficits early in the OSA syndrome. The gray matter loss occurs within sites involved in motor regulation of the upper airway as well as in areas contributing to cognitive function.

Adult↗

PubMed2003

Phenotypic and functional characterization of blood gammadelta T cells in sleep apnea.

Hypoxia-induced lymphocyte dysfunction may be implicated in endothelial cell damage in obstructive sleep apnea (OSA) syndrome. gammadelta T cells' unique migration, cytotoxic features, and accumulation in atherosclerotic plaques are considered critical in cardiovascular disorders. We characterized the phenotype, cytokine profile, adhesion properties, and cytotoxicity of gammadelta T cells in patients with OSA and control subjects. The following is a summary of our major findings regarding OSA gammadelta T cells: (1) a significant increase in the expression of the inhibitory natural killer B1 receptors was found; (2) the intracellular content of proinflammatory cytokines tumor necrosis factor (TNF)-alpha and interleukin-8 was increased, and the content of the antiinflammatory cytokine interleukin-10 was decreased; (3) gammadelta T cells of patients with OSA adhered significantly more avidly to nonactivated endothelial cells in culture than those of control subjects; (4) L-selectin expression was higher; (5) anti-E/P-selectin antibodies and anti-TNF-alpha antibodies decreased the adhesion index of OSA gammadelta T lymphocytes/endothelial cells but not of control subjects; and (6) cytotoxicity of OSA gammadelta T lymphocytes against endothelial cells in culture was 2.5-fold higher than that of control subjects and could be prevented by pretreatment with anti-TNF-alpha. Collectively these data implicate gammadelta T lymphocyte function in atherogenic sequelae in OSA.

Arteriosclerosis↗

PubMed2004

Upper airway muscle inflammation and denervation changes in obstructive sleep apnea.

Inflammatory cell infiltration and afferent neuropathy have been shown in the upper airway (UA) mucosa of subjects with obstructive sleep apnea (OSA). We hypothesized that inflammatory and denervation changes also involve the muscular layer of the pharynx in OSA. Morphometric analysis was performed on UA tissue from nonsnoring control subjects (n = 7) and patients with OSA (n = 11) following palatal surgery. As compared with control subjects, inflammatory cells were increased in the muscular layer of patients with OSA, with CD4+ and activated CD25+ T cells (both increased approximately threefold) predominating. Inflammation was also present in UA mucosa, but with a different pattern consisting of CD8+ (2.8-fold increase) and activated CD25+ (3.2-fold increase) T cell predominance. As ascertained by immunoreactivity for the panneuronal marker PGP9.5, there was a dramatic (5.7-fold) increase in intramuscular nerve fibers in OSA patients compared with control subjects, as well as direct evidence of denervation based on positive immunostaining of the muscle fiber sarcolemmal membrane for the neural cell adhesion molecule in patients with OSA. These data suggest that inflammatory cell infiltration and denervation changes affect not only the mucosa, but also the UA muscle of patients with OSA. This may have important implications for the ability to generate adequate muscular dilating forces during sleep.

Axons↗

PubMed2004

Increased levels and activity of matrix metalloproteinase-9 in obstructive sleep apnea syndrome.

Matrix metalloproteinases (MMPs) are involved in the pathogenesis of cardiovascular diseases. We examined serum levels of MMP-9 and its inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), activity of MMP-9, and the effect of nasal continuous positive airway pressure (nCPAP) in patients with obstructive sleep apnea syndrome (OSAS). After polysomnography, venous blood was collected at 5:00 A.M. from 44 patients with OSAS and 18 control subjects who were obese, and serum levels of MMP-9, TIMP-1, and enzymatic activity of MMP-9 were measured. In addition, the effects of 1 month of treatment with nCPAP were studied in patients with moderate to severe OSAS. Although serum levels of MMP-9 (p < 0.03) and MMP-9 activity (p < 0.01) were higher in patients with OSAS than in control subjects who were obese, TIMP-1 levels did not differ significantly. In patients with OSAS, the severity of OSAS was the primary factor influencing levels (p < 0.01) and activity (p < 0.01) of MMP-9. nCPAP significantly decreased serum levels (p < 0.01) and activity (p < 0.001) of MMP-9 but did not affect TIMP-1 levels. Therefore, OSAS may increase risks of cardiovascular morbidity, and nCPAP might be useful for decreasing these risks.

Humans↗

PubMed2005

Increased carotid intima-media thickness and serum inflammatory markers in obstructive sleep apnea.

Increased carotid intima-media thickness (IMT) and increased serum levels of inflammatory markers, such as C-reactive protein (CRP), interleukin (IL)-6, and IL-18, are associated with an increased risk of cardiovascular and cerebrovascular diseases. The aim of this study was to evaluate whether carotid IMT, a useful marker for early atherosclerosis, is associated with these inflammatory markers in patients with obstructive sleep apnea (OSA). Carotid IMT was investigated with ultrasonography in 36 patients with OSA and 16 obese control subjects. Serum levels of CRP, IL-6, and IL-18 were measured at 5:00 A.M. Carotid IMT (p < 0.001) and serum levels of CRP (p < 0.003), IL-6 (p < 0.005), and IL-18 (p < 0.03) of patients with OSA were significantly higher than those of obese control subjects. Carotid IMT was significantly correlated with serum levels of CRP (r = 0.61, p = 0.0001), IL-6 (r = 0.41, p = 0.01), and IL-18 (r = 0.45, p = 0.005), duration of OSA-related hypoxia (r = 0.60, p = 0.0001), and severity of OSA (r = 0.50, p = 0.002). In addition, the primary factor influencing carotid IMT was duration of hypoxia during total sleep time (p = 0.036). These results suggest that OSA-related hypoxia and systemic inflammation might be associated with the progression of atherosclerosis and thus might increase the risks of cardiovascular and cerebrovascular morbidity in patients with OSA.

Adult↗