Impaired circadian variation of platelet activity in patients with sleep apnea

Background  

Cardiovascular diseases are frequent in patients with obstructive sleep apnea (OSAS). There is evidence that the day–night pattern of myocardial infarction and sudden cardiac death observed in the general population is altered in patients with OSAS. This study investigates potential abnormalities in the circadian profiles of platelet activity in OSAS.     

Clinical perspective: monitoring sodium oxybate-treated narcolepsy patients for the development of sleep-disordered breathing

Purpose  

While the symptoms of narcolepsy are often amenable to treatment with sodium oxybate (SXB), the respiratory effects of long-term SXB treatment have not been systematically studied. Recent reports have implicated SXB with several cases of worsening sleep-related breathing disturbances and accidental death. In addition, these patients are at risk for obesity, which may aggravate co-morbid obstructive sleep apnea.     

Is obstructive sleep apnea syndrome a risk factor for auditory pathway?

Purpose  

The transduction mechanism of the inner ear and the transmission of nerve impulses along the auditory way are highly dependent upon the cochlear oxygen supply. Several studies have considered the possibility that obstructive sleep apnea–hypopneas during sleep can interfere with these processes, and the results are not uniform. The aim of the study is to evaluate the auditory function in adult patients affected by severe obstructive sleep apnea syndrome (OSAS).     

Changes in cerebral hemoglobin indices in obstructive sleep apnea syndrome with nasal continuous positive airway pressure treatment

Introduction  

This study examined both the relationship between the changes in the brain tissue hemoglobin indices and SpO₂ during sleep in patients with obstructive sleep apnea syndrome (OSAS) and the effect of nasal continuous positive airway pressure (CPAP) treatment on hemoglobin indices.     

Correlation between the intima-media thickness and Framingham risk score in patients with sleep apnea syndrome

Background

In the present study, we want to demonstrate the correlation between obstructive sleep apnea syndrome (OSAS) whose independent effect on carotid artery intima-media thickness (IMT) was demonstrated, with Framingham risk score (FRS) showing the overall cardiovascular risk.

Methods

IMT of the carotid artery was measured with ultrasonography and 10-year risk of coronary heart disease (CHD) was defined with FRS in 90 consecutive patients referred to our sleep clinic and who underwent polysomnography (PSG), with vascular risk factors and without a clinical atherosclerotic disease.

Results

IMT and FRS were found to be statistically significantly increased in the severe OSAS group compared to the other two groups. Carotid IMT was found to be significantly positively correlated with, apnea-hypopnea index (AHI), oxygen desaturation index (ODI) and time duration with oxygen saturation (SpO₂) <90%, and negatively correlated with minimum oxygen saturation at sleep (minimum SpO₂) and mean SpO₂. In control and mild OSAS group IMT and FRS have significantly positive correlation (r: 0.501, P: 0.027; r: 0.625, P<0.001), while in severe OSAS group no significant correlation was detected between IMT and FRS (r: 0.321, P: 0.06). In the regression analysis AHI and ODI were found to be an independent predictor of carotid IMT. ODI was found to have an independent effect on the progression of atherosclerosis.

Conclusions

Increased carotid IMT in severe OSAS group could not be explained with the classical risk factors. In this respect, FRS might be insufficient to determine correctly the cardiovascular risk and protection strategies against the disease in OSAS patients.KEYWORDS : Carotid artery, Framingham risk score (FRS), sleep apnea     

Comparison of the automatic analysis versus the manual scoring from ApneaLink™ device for the diagnosis of obstructive sleep apnoea syndrome

Objective  

The purpose of this study was to compare the performance of the automated detection versus the manual scoring from the ApneaLink™ device to diagnose obstructive sleep apnoea syndrome (OSAS).     

Factors that influence CPAP adherence: an overview

Background  

Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea syndrome (OSAS). Consistent adherence to CPAP improves the patient’s longevity and quality of life as well as public safety. However, nonadherence is a significant contributor to the growing burden of untreated OSAS, and is associated with negative consequences for the patient, public safety, and the healthcare system.     

Quality of life,compliance, sleep and nasopharyngeal side effects during CPAP therapy with and without controlled heated humidification

Purpose  

To determine the effect of a controlled heated breathing tube humidifier (cHH) on the quality of life (QOL), compliance and nasopharyngeal side effects during continuous positive airway pressure (CPAP) therapy in patients with obstructive sleep apnea syndrome (OSAS) in comparison with conventional CPAP.     

Polysomnographic characteristics of daytime sleepiness in obstructive sleep apnea syndrome

Purpose  

The study is intended to explore the nocturnal sleep determinants for excessive daytime sleepiness (EDS) in patients with obstructive sleep apnea syndrome (OSAS).     

Red Cell Distribution Width in Patients with Obstructive Sleep Apnea Syndrome

Background  

Red cell distribution width (RDW) has been shown to be associated with adverse outcomes in left-sided heart failure, pulmonary hypertension, and in patients in the ICU. However, the role of RDW is unknown in patients with obstructive sleep apnea syndrome (OSAS), especially in OSAS patients with cardiovascular diseases.     

N-terminal pro-B-type natriuretic peptide and functional capacity in patients with obstructive sleep apnea

The obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular abnormalities including left ventricular hypertrophy, left ventricular diastolic dysfunction, and endothelial dysfunction. The present study evaluated whether N-terminal pro-B-type natriuretic peptide (NT-proBNP) and peak oxygen consumption (peak VO₂), both integral markers of cardiovascular function, are related to OSAS severity. In addition, we tested whether NT-proBNP levels depend on body composition in OSAS patients, similar to what has been reported in patients without OSAS. Eighty-nine patients with untreated OSAS underwent NT-proBNP measurement, dual X-ray absorptiometry, and cardiopulmonary exercise testing. In a representative subgroup (n = 32), transthoracic echocardiography was performed. The severity of OSAS was classified based on apnea–hypopnea index (AHI) values as mild (AHI 5–15 h⁻¹), moderate (AHI 15–30 h⁻¹), and severe (AHI >30 h⁻¹). OSAS was mild in 19 (21%), moderate in 21 (24%), and severe in 49 (55%) patients. NT-proBNP levels did not differ among patients with mild [30 (10–57)], moderate [37 (14–55)], and severe [24 (13–49) pg/ml; p = 0.8] OSAS and were not related to body mass index (r = 0.07; p = 0.5), percent lean body mass (r = −0.17; p = 0.1), and percent fat mass (r = 0.18; p = 0.1). Percent predicted peak VO₂ was on average normal and did not differ among patients with mild (115 ± 26), moderate (112 ± 23), and severe OSAS (106 ± 29%; p = 0.4). Body weight-indexed peak VO₂ did not differ among patients with mild (31.9 ± 10.3), moderate (32.1 ± 7.9), and severe OSAS (30.0 ± 9.9 ml kg⁻¹ min⁻¹; p = 0.6) either. Lower NT-proBNP (β = −0.2; p = 0.02) was independently but weakly associated with higher body weight-indexed peak VO₂. In the echocardiography subgroup, NT-proBNP was not significantly related to left ventricular mass index (r = 0.26; p = 0.2). In conclusion, NT-proBNP and peak VO₂ are not related to OSAS severity, and NT-proBNP poorly reflects left ventricular hypertrophy in OSAS. The lack of a relationship between NT-proBNP and OSAS severity is not due to a significant influence of body composition on NT-proBNP. There is an association between higher NT-proBNP and lower peak VO₂, indicating that NT-proBNP is a marker of cardiorespiratory fitness in patients with OSAS. However, the association is too weak to be clinically useful.     

Sleep-disordered breathing,behavior, and academic performance in Taiwan schoolchildren

Objective  

The behaviors of children may be affected by sleep-disordered breathing (SDB). This study adopts a cross-sectional approach to investigate the relationship between the sleep apneas–hypopneas index during sleep and the behavioral and academic performance of schoolchildren in Taiwan.     

Endothelial dysfunction and inflammatory reactions of elderly and middle-aged men with obstructive sleep apnea syndrome

Introduction  Obstructive sleep apnea syndrome (OSAS) is considered to be associated with cardiovascular complications, and atherosclerosis could mediate this relationship. Cardiovascular risk factors of OSAS still need to be elucidated in elderly patients, since studies about the association between OSAS and cardiovascular diseases have been done mainly in middle-aged adults. To investigate whether endothelial dysfunction, as an early marker of atherosclerosis, and inflammatory responses in OSAS were affected by age, we studied flow-mediated dilatation (FMD) and C-reactive protein (CRP) in elderly and middle-aged patients with OSAS. Materials and methods  This study enrolled 161 male subjects of 117 middle-aged (35–59 years old) and 44 elderly (≥60 years old) patients with OSAS. After they finished nocturnal polysomnography (NPSG), FMD was measured on the brachial artery and blood samples were obtained to determine serum CRP levels. Results and discussion  FMD was significantly lower in the elderly patients (p = 0.04), but no difference was observed between two age groups in body mass index (BMI), neck circumference, waist-to-hip ratio, apnea hypopnea index (AHI), serum CRP level, or NPSG findings related with nocturnal hypoxemia such as average O₂ saturation, percentage of time below 90% O₂ saturation, and oxygen desaturation index (ODI). From the results of stepwise multiple linear regression analysis, the lowest oxygen saturation was a significant determinant of FMD (β = 0.25, p < 0.01, adjusted R ² = 6%), and BMI (β = 0.22, p < 0.05) and waist-to-hip ratio (β = 0.21, p < 0.05) were significant variables to explain CRP (adjusted R ² = 11%, p < 0.01) in the middle aged patients. In the elderly patients, no variable was significant for predicting FMD, but AHI was significant determinant of CRP (β = 0.46, p < 0.01, adjusted R ² = 19%, p < 0.01). In predicting cardiovascular risks of OSAS, both hypoxia and obesity should be considered in the middle-aged group, whereas nocturnal respiratory disturbances are important in the elderly group.     

Oxidative and carbonyl stress in patients with obstructive sleep apnea treated with continuous positive airway pressure

Purpose  

The pathogenesis of cardiovascular complications of obstructive sleep apnea syndrome (OSAS) can be explained by oxidative and carbonyl stress due to oxygenation and reoxygenation injury during sleep. This hypothesis has yet to be proved experimentally, although several clinical observations have found increased oxidative damage in plasma. Continuous positive airway pressure (CPAP) improves symptoms and prognosis of patients with OSAS.     

Plasma visfatin levels in severe obstructive sleep apnea—hypopnea syndrome

Background  

Obstructive sleep apnea syndrome (OSAS) is associated with obesity and insulin resistance. Visfatin is an insulin-mimicking adipokine, which is considered a link between obesity and insulin resistance. Aim of this study was to evaluate levels of plasma visfatin in patients with severe OSAS and examine their potential correlation with sleep characteristics and several biochemical parameters.     

The effect of exercise on obstructive sleep apnea: a randomized and controlled trial

Purpose  

The aim of the study was to assess the effect of breathing and physical exercise on pulmonary functions, apnea-hypopnea index (AHI), and quality of life in patients with obstructive sleep apnea syndrome (OSAS).     

Obstructive sleep apnoea syndrome promotes reversal albuminuria during sleep

Introduction  

Sleep apnoea syndrome (OSAS) may induce albuminuria during sleep which could reflect one of the possible pathogenetic mechanisms regarding cardiovascular risk.     

A comparison of polysomnographic variables between obese adolescents with polycystic ovarian syndrome and healthy,normal-weight and obese adolescents

Purpose  

The purpose of this study was to determine the differences in polysomnographic variables between obese adolescents with polycystic ovarian syndrome (PCOS) and healthy, normal-weight and obese controls, as the prevalence of obstructive sleep apnea syndrome (OSAS) is increased in adults with PCOS.     

Adherence to CPAP therapy improves quality of life and reduces symptoms among obstructive sleep apnea syndrome patients

Purpose  

The aim of the study was to asses quality of life and symptoms of obstructive sleep apnea syndrome (OSAS) patients after adhering to 6 months of continuous positive airway pressure (CPAP) treatment.