Obstructive sleep apnea and vitamin D level: Has the dust settled?

Obstructive sleep apnea and vitamin D deficiency are associated with multiple complications with increased morbidity and mortality. However, the relationship between these two entities remains unclear, with clinical studies demonstrating contradictory results. This narrative review aims to present the current evidence and understanding of this relationship and discuss the possible mechanisms linking these two disease entities. Finally, we summarize and propose areas of opportunity for future research.

International Survey of the Tools Used for Assessment, Monitoring and Management of Home Mechanical Ventilation Patients

BACKGROUND

There are limited data reporting diagnostic practices, compared to clinical guidelines, for patients with chronic respiratory failure requiring home mechanical ventilation (HMV). There are no data detailing the current use of downloaded physiological monitoring data in day-to-day clinical practice during initiation and follow up of patients on HMV. This survey reports clinicians' practices, with a specific focus on the clinical approaches employed to assess, monitor and manage HMV patients.

METHODS

A web-based international survey was open between 1 January and 31 March 2023.

RESULTS

In total, 114 clinicians responded; 84% of the clinicians downloaded the internal physiological ventilator data when initiating and maintaining HMV patients, and 99% of the clinicians followed up with patients within 3 months. Adherence, leak and the apnea-hypopnea index were the three highest rated items. Oxygen saturation was used to support a diagnosis of nocturnal hypoventilation and was preferred over measurements of carbon dioxide. Furthermore, 78% of the clinicians reviewed data for the assessment of patient ventilator asynchrony (PVA), although the confidence reported in identifying certain PVAs was reported as unconfident or extremely unconfident.

CONCLUSIONS

This survey confirmed that clinical practice varies and often does not follow the current guidelines. Despite PVA being of clinical interest, its clinical relevance was not clear, and further research, education and training are required to improve clinical confidence.

Significance of Plasma Irisin, Adiponectin, and Retinol Binding Protein-4 Levels as Biomarkers for Obstructive Sleep Apnea Syndrome Severity

OBJECTIVE

Obstructive sleep apnea syndrome (OSAS) is a common sleep disorder that is caused by the reduction or cessation of airflow in the upper airway. Irisin, retinol-binding protein-4 (RBP-4), and adiponectin are the three significant factors in the metabolic process of the human body. The objective of this study was to investigate whether plasma irisin, RBP-4, and adiponectin levels are associated with the severity of OSAS.

METHODS

According to inclusion and exclusion criteria, 125 patients with OSAS and 46 healthy, gender-matched controls were included in this study. The patients were classified according to the apnea hypopnea index (AHI) as 14 mild cases (5 < AHI < 15), 23 moderate OSAS cases (15 < AHI < 30), and 88 severe OSAS cases (AHI > 30). The plasma irisin, RBP-4, and adiponectin levels were measured and compared between groups.

RESULTS

RBP-4 levels were higher in severe OSAS compared to other groups, and irisin levels were significantly lower in severe OSAS compared to other groups. There was a negative correlation between irisin and RBP-4 (r = -0.421; p < 0.001), and irisin and AHI (r = -0.834; p < 0.001), and a positive correlation between irisin and adiponectin (r = 0.240; p = 0.002). There was a negative correlation between RBP-4 and adiponectin (r = -0.507; p < 0.001) and a positive correlation between RBP-4 and AHI (r = 0.473; p < 0.001). As a predictor of OSAS, adiponectin showed the highest specificity (84.8%) and RBP-4 the highest sensitivity (92.0%).

CONCLUSION

Circulating adiponectin, irisin, and RBP-4 may be new biomarkers in OSAS patients in addition to risk factors such as diabetes, obesity, and hypertension. When polysomnography is not available, these parameters and clinical data can be used to diagnose the disease. As a result, patients with an AHI score greater than thirty should be closely monitored for metabolic abnormalities.

A Prospective Study on Obstructive Sleep Apnea, Clinical Profile and Polysomnographic Variables

Background: Obstructive sleep apnea (OSA) is characterized by recurring episodes of pharyngeal collapse, which can partially or completely block airflow during sleep and cause cardiorespiratory and neurological imbalances. Therefore, the purpose of this study was to assess OSA and the relationship between AHI and polysomnographic characteristics in OSA patients. Methodology: A prospective study was conducted at the Department of Pulmonology and Sleep Medicine for two years. All 216 participants underwent polysomnography, and 175 of them were reported to have OSA (AHI ≥ 5), while 41 of them did not (AHI < 5). ANOVA and Pearson's correlation coefficient test were performed. Results: In terms of the study population's average AHI, Group 1 had 1.69 ± 1.34, mild OSA had 11.79 ± 3.55, moderate OSA had 22.12 ± 4.34, and severe OSA was found to have 59.16 ± 22.15 events/hour. The study group's average age was 53.77 ± 7.19 out of 175 OSA patients. According to AHI, the BMI for mild OSA was 31.66 ± 8.32 kg/m², for moderate OSA, it was 30.52 ± 3.99 kg/m², and for severe OSA, it was 34.35 ± 8.22 kg/m². The average number of oxygen desaturation events and snoring duration were 25.20 ± 18.63 and 24.61 ± 28.53 min, respectively. BMI (r = 0.249, p < 0.001), average oxygen saturation (r = -0.387, p < 0.000), oxygen desaturation (r = 0.661, p < 0.000), snoring time (r = 0.231, p < 0.002), and the number of snores (r = 0.383, p < 0.001) were the polysomnographic variables that showed significant correlations with AHI in the study group. Conclusions: In this study, a substantial prevalence of obesity and a high OSA frequency were found in men. Our research showed that individuals with obstructive sleep apnea experience nocturnal desaturations. Polysomnography is the primary test for early detection of this treatable condition.

Patient-Defined Goals for Obstructive Sleep Apnea Treatment

Objectives

To characterize the treatment goals and values of adult patients with obstructive sleep apnea (OSA).

Study Design

Mixed methods design based on semistructured interviews followed by cross-sectional surveys.

Setting

Academic medical center and integrated managed care consortium.

Methods

Phase 1 involved qualitative analysis of focus groups and interviews to define treatment goal categories. Phase 2 included analysis of cross-sectional surveys on most important treatment goals from patients with OSA presenting to sleep surgery clinic. Positive airway pressure (PAP) use, Epworth Sleepiness Scale score, and apnea-hypopnea index were obtained to determine influences on goal choices.

Results

During focus groups and interviews, treatment goal themes identified included improving sleep quality, reducing daytime sleepiness, snoring sound reduction, and health risk reduction. In phase 2, 536 patients were surveyed, and they reported the primary treatment goals of health risk reduction (35%), sleep quality improvement (28%), daytime sleepiness improvement (21%), and snoring sound reduction (16%). The primary treatment goal was associated with age (P < .0001), excessive daytime sleepiness (Epworth Sleepiness Scale score >10, P < .0001), PAP use status (P < .0001), and OSA severity (apnea-hypopnea index, P < .0001). Severity of OSA was associated with increasing proportion of patients choosing health risk reduction as the main treatment goal (P < .05).

Conclusions

Adult OSA treatment goal choices vary with age, symptoms, PAP history, and OSA severity. Understanding patient-specific goals is the essential first step in the shared decision-making process when choosing surgical or nonsurgical treatments. Ultimately, goal-focused discussions ensure alignment of priorities and definitions of success between the patient and the provider.

Increased plasma ANGPTL7 levels with increased obstructive sleep apnea severity

BACKGROUND

Weight-loss surgery is one of the recommended methods for treating obstructive sleep apnea (OSA) in obese patients. While weight reduction is critical to relieve symptoms of OSA, the biochemical factors involved in post-surgery improvement are still unknown. We aimed to explore the link between ANGPTL7 and OSA in patients with different OSA severity. Furthermore, we examined the effect of treating OSA with bariatric surgery on ANGPTL7 level.

METHODS

We quantified levels of circulating ANGPTL7 in fasting plasma and adipose tissue samples of 88 participants before and after bariatric surgery. Confocal microscopy analyses were also performed to assess the ANGPTL7 expression in subcutaneous white adipose tissue biopsies obtained from people with moderate-to-severe OSA compared to those with none or mild OSA. The study involved 57 individuals with none or mild OSA and 31 patients with moderate-to-severe OSA.

RESULTS

Levels of circulating ANGPTL7 were significantly higher in people with moderate-to-severe OSA (1440 ± 1310 pg/ml) compared to the none or mild OSA group (734 ± 904 pg/ml, p = 0.01). The increase in ANGPTL7 correlated significantly and positively with the apnea-hypopnea index (AHI, r = .226, p = .037), and AHI-supine (r = .266, p = .019) in participants with moderate-to-severe OSA. Multivariate logistic regression analysis demonstrated an association between ANGPTL7 and OSA severity (log₂ ANGPTL7; OR =1.24, p = 0.024). ANGPTL7 levels exhibited significant positive correlations with the levels of TG and oxLDL (p-value = 0.002 and 0.01 respectively). Bariatric surgery reduced the levels of both ANGPTL7 and AHI significantly.

CONCLUSION

Here we report significantly increased levels of ANGPTL7 both in the circulation and in adipose tissue of patients with OSA, which concurred with increased inflammation and OSA severity. Levels of ANGPTL7 decreased significantly as OSA showed a significant improvement post-surgery supporting a potential role for ANGPTL7 in either OSA progression or a role in an OSA-related mechanism.

Clinical Predictors of Mixed Apneas in Patients with Obstructive Sleep Apnea (OSA)

PURPOSE

Mixed events in obstructive sleep apnea (OSA) patients (mixed-OSA) indicate respiratory regulation instability and are essential for OSA pathogenesis and prognosis. It also shows a decreased compliance with continuous positive airway pressure (CPAP). Using predictors to identify mixed-OSA has significant clinical guidance for OSA precise diagnosis and treatment. This study aimed to establish a simple and accessible method for rapid screening of mixed-OSA, thus promoting OSA precise diagnosis.

PATIENTS AND METHODS

A total of 907 patients with suspected OSA were screened, of which 513 OSA patients, including 344 with pure-OSA and 169 with mixed-OSA, were finally included in the study. The clinical characteristics and polysomnography (PSG) parameters of the two OSA groups were compared. Multivariate logistic regression analysis was used to investigate the factors affecting the morbidity of mixed-OSA. The receiver operating characteristic (ROC) curve was used to explore if some convenient PSG parameters can be used to predict mixed-OSA.

RESULTS

About 33% of OSA patients were identified as mixed-OSA. Multivariate logistic regression analysis showed that apnea hypopnea index (AHI) and lowest oxygen saturation (LSO₂) were independently associated with mixed-OSA after adjusting for age, sex, body mass index (BMI), smoking, drinking, hypertension, and Epworth Sleepiness Score (ESS) (AHI: OR=1.046, 95% CI 1.032-1.060, P < 0.001; LSO₂: OR=0.958, 95% CI 0.936-0.981, P < 0.001). ROC curve analysis showed that AHI > 47 or LSO₂ < 77% indicated mixed-OSA. The sensitivity and specificity of AHI> 47 was 0.952 and 0.652, respectively, and 0.822 and 0.675 for LSO₂ < 77%, respectively.

CONCLUSION

Our research found that AHI > 47 or LSO₂ < 77% are independently associated with mixed-OSA and can be used to quickly identify the occurrence of mixed-OSA. Therefore, this study can help detect mixed-OSA and precise individual diagnosis of OSA patients.

The Relationship Between HIF1α and Clock Gene Expression in Patients with Obstructive Sleep Apnea

PURPOSE

In this study, we aimed to investigate the precise relationship between hypoxia-inducible factor 1α (HIF1α), circadian clock genes, and OSA.

METHODS

We recruited 21 patients with OSA and 22 age-matched controls who underwent polysomnography and had their peripheral blood collected on the evening before and the morning after sleep. OSA was defined as an apnea hypopnea index (AHI) ≥15 events/h. Patients in which T90 > 0 were defined as having nocturnal hypoxemia (NH) and were referred to as the NH group. The mRNA levels of HIF1α, HIF1β and several clock genes (Timeless, Clock, Bmal1, Per1, Per2, Per3, Cry1, Cry2, Ck1δ, Rorα, NR1D1, and NPAS2) were determined by RT-qPCR. The percentage difference in gene expression levels when compared between the morning and evening was then determined as referred to as morning-evening variation (MEV).

RESULTS

The MEV for HIF1α mRNA expression in OSA patients increased significantly by 23% (P = 0.008) when compared to patients without OSA. The gene expression levels of Timeless (P = 0.038) and Cry2 (P = 0.012) decreased with AHI. The MEV of Bmal1, Rorα, and HIF1α mRNA levels were upregulated by 16% (P = 0.006), 14% (P = 0.027), and 25% (P = 0.005), respectively, in participants with NH when compared to those without NH. Furthermore, the MEV for HIF1α mRNA levels was positively correlated with the MEV of Bmal1, Cry1, and CK1δ mRNA levels (R = 0.638, P < 0.001; R = 0.327, P = 0.002; R = 0.332, P = 0.001, respectively) and negatively correlated with LSpO₂ (R = -0.464, P =0.009) and Mean SpO₂ (R = -0.500, P = 0.003).

CONCLUSION

Our data suggest that patients with OSA or NH tend to develop circadian rhythm disorders that may be induced by the hypoxia-mediated augmentation of HIF1α gene expression in OSA.

Time Under 90% Oxygen Saturation and Systemic Hypertension in Patients with Obstructive Sleep Apnea Syndrome

PURPOSE

The diagnosis and severity of obstructive sleep apnea (OSA) are commonly based on the apnea hypopnea index (AHI). However, patients with similar severity AHIs may show widely varying comorbidities and risks for cardiovascular disease, which may be associated with different severities of nocturnal hypoxia. The percentage of cumulative time with oxygen saturation below 90% in total sleep time (T90) is receiving increasing attention in OSA research because it describes the duration and degree of hypoxia during the whole sleep. This study aimed to explore the distribution of T90 in OSA patients with similar severity and to evaluate the relationship between T90 and hypertension.

PATIENTS AND METHODS

A total of 775 patients with OSA were enrolled in this study, all participants were divided into groups according to the T90 value: light hypoxia (T90≤5%), mild hypoxia (T90 accounted for 5-10%), moderate hypoxia (T90 accounted for 10-25%), and severe hypoxia (T90>25%). Multivariate logistic regression analysis was performed to assess the association between T90 and hypertension.

RESULTS

Of the patients with mild OSA, 94.33% had light hypoxia, and 88.64% of moderate OSA patients had light hypoxia. The proportions of light, mild, moderate, and severe hypoxia among patients with severe OSA were 28.60%, 17.69%, 21.40%, and 32.31%, respectively. After adjustment for potential confounders, the risk of hypertension in patients with severe OSA increased according to the severity categories of T90. The odds ratio for T90 accounting for 10-25% relative to T90≤5% was 2.544 (95%confidence interval, 1.254-5.164; P=0.010) and as high as 2.692 (95%confidence interval, 1.403-5.166; P=0.003) in patients with T90>25%.

CONCLUSION

OSA patients with similar degree of AHI may have different T90 values, especially in severe OSA. A higher T90 was independently associated with the risk of hypertension after adjustment for traditional risk factors in patients with severe OSA. Our findings highlight the potential role for T90 in predicting hypertension in patients severe OSA.

Improving Adherence to Myofunctional Therapy in the Treatment of Sleep-Disordered Breathing

Myofunctional therapy (MT) is used to treat sleep-disordered breathing. However, MT has low adherence-only ~10% in most studies. We describe our experiences with MT delivered through a mobile health app named Airway Gym®, which is used by patients who have rejected continuous positive airway pressure and other therapies. We compared ear, nose, and throat examination findings, Friedman stage, tongue-tie presence, tongue strength measured using the Iowa oral performance instrument (IOPI), and full polysomnography before and after the 3 months of therapy. Participants were taught how to perform the exercises using the app at the start. Telemedicine allowed physicians to record adherence to and accuracy of the exercise performance. Fifty-four patients were enrolled; 35 (64.8%) were adherent and performed exercises for 15 min/day on five days/week. We found significant changes (p < 0.05) in the apnoea-hypopnoea index (AHI; 32.97 ± 1.8 to 21.9 ± 14.5 events/h); IOPI score (44.4 ± 11.08 to 49.66 ± 10.2); and minimum O2 saturation (80.91% ± 6.1% to 85.09% ± 5.3%). IOPI scores correlated significantly with AHI after the therapy (Pearson r = 0.4; p = 0.01). The 19 patients who did not adhere to the protocol showed no changes. MT based on telemedicine had good adherence, and its effect on AHI correlated with IOPI and improvement in tongue-tie.

[Objective sleep characteristics and risk factors for sleep apnea in heart failure patients with different left ventricular ejection fraction]

OBJECTIVE

To investigate the objective sleep characteristics and the independent risk factors for sleep apnea in heart failure (HF) patients with different left ventricular ejection fractions (LVEF).

METHODS

A total of 107 patients with chronic HF hospitalized in the Department of Cardiology of our hospital from April, 2019 to October, 2020 were included in this study. According to the LVEF measured by echocardiography, the patients were divided into reduced ejection fraction (HFrEF) group (n=35), mid-range ejection fraction (HFmrEF) group (n=21), and preserved ejection fraction (HFpEF) group (n=51). The baseline demographic and clinical characteristics of the patients were recorded. To assess the objective sleep characteristics, whole night polysomnography was scheduled for all the patients. Spearman correlation and multinomial logistic regression analyses were used to explore the factors affecting objective sleep characteristics.

RESULTS

The patients in HFpEF group had significantly lower proportion of non-rapid eye movement sleep stage 1, apnea hypopnea index (AHI), and central sleep apnea (CSA) than those in HFrEF group (all P < 0.05). The baseline demographic data or sleep structures in HFmrEF group did not differ significantly from those in the other two groups. Spearman correlation analysis revealed significant correlations of the male sex, diuretics use, NT-proBNP, LVEF, and total cholesterol levels with the severity of AHI (all P < 0.05). After adjusting for potential confounders, multiple logistics regression analysis showed that age, drinking, and LVEF levels were independently associated with the severity of AHI (all P < 0.05).

CONCLUSION

Abnormal objective sleep architectures occur in all HF patients, manifested mainly by sleep apnea. The incidences of sleep apnea and CSA are lower in patients with HFpEF than in those with HFrEF. Age, drinking, and LVEF levels are independent risk factors for the occurrence and severity of sleep apnea.

Predictive Factors for Efficacious Oral Appliance Therapy in Moderate to Severe Obstructive Sleep Apnea Patients

OBJECTIVES/HYPOTHESIS

Oral appliances (OAs) are a treatment for obstructive sleep apnea hypopnea syndrome (OSAHS). The main objective of the study was to determine the predictive factors of OA efficacy. The secondary objective was to measure the efficacy rates and determine OAs' tolerance and dropout.

STUDY DESIGN

Retrospective study.

METHODS

Efficacy results of the OAs based on the apnea hypopnea index (AHI) reduction, complications, and dropout rates were retrospectively collected from 347 patients with a moderate to severe OSAHS treated by a retention OA. The procedure was entirely performed by otolaryngologists.

RESULTS

The AHI with OA was more significantly reduced in patients with a higher initial AHI and a higher initial body mass index but reduction was not related to age and not proportional to the degree of mandibular advancement. The 50% AHI reduction rate after OA was 65.2%, the AHI ≤5/hr rate after OA was 26.1%, and the <50% AHI reduction and residual AHI > 10/hr rate was 50.1%. The OA significantly reduced the mean AHI (-14.9/hr, P < .0001). In 7.8% of patients, the AHI increased with OA. Seven patients (1.5%) experienced adverse effects. Thirty-seven (7.8%) patients stopped using OA mainly because of its ineffectiveness. Advancement can be considered beyond the initial maximal advancement. It can be effective sometimes; however, increasing advancement did not significantly reduce AHI.

CONCLUSIONS

OA is an effective and well-tolerated treatment for moderate to severe OSAHS. This treatment was effective for reduction of the AHI ≥50% in two-thirds of cases studied and it should be considered in more cases.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E2089-E2096, 2021.

Estimating a Sleep Apnea Hypopnea Index Based on the ERB Correlation Dimension of Snore Sounds

This paper proposes a new perspective of analyzing non-linear acoustic characteristics of the snore sounds. According to the ERB (Equivalent Rectangular Bandwidth) scale used in psychoacoustics, the ERB correlation dimension (ECD) of the snore sound was computed to feature different severity levels of sleep apnea hypopnea syndrome (SAHS). For the training group of 93 subjects, snore episodes were manually segmented and the ECD parameters of the snores were extracted, which established the gaussian mixture models (GMM). The nocturnal snore sound of the testing group of another 120 subjects was tested to detect SAHS snores, thus estimating the apnea hypopnea index (AHI), which is called AHIECD. Compared to the AHIPSG value of the gold standard polysomnography (PSG) diagnosis, the estimated AHIECD achieved an accuracy of 87.5% in diagnosis the SAHS severity levels. The results suggest that the ECD vectors can be effective parameters for screening SAHS.

The Effect of Lateral Pharyngeal Collapse Patterns on Therapy Response in Upper Airway Stimulation Surgery

OBJECTIVES

Obstructive sleep apnea (OSA) is characterized by repeated upper airway collapse while sleeping which leads to intermittent hypoxemia. Upper airway stimulation (UAS) is a commonly practiced modality for treating OSA in patients who cannot tolerate, or do not benefit from, positive airway pressure (PAP). The purpose of this study is to identify the effect of lateral pharyngeal collapse patterns on therapy response in UAS.

METHODS

A retrospective cohort study from a single, tertiary-care academic center was performed. Patients who underwent UAS between October 2016 and July 2019 were identified and analyzed. Drug-induced Sleep Endoscopy (DISE) outcomes between Apnea-Hypopnea Index (AHI) responders and AHI non-responders were compared. Those with complete concentric collapse at the velopharynx were not candidates for UAS.

RESULTS

About 95 patients that underwent UAS were included in this study. Pre- to Post-UAS demonstrated significant improvements in Epworth Sleepiness Scale (12.0 vs 4.0, P = .001), AHI (29.8 vs 5.4, P < .001) and minimum oxygen saturation (79% vs 83%, P < .001). No DISE findings significantly predicted AHI response after UAS. Specifically, multiple types of lateral pharyngeal collapse patterns did not adversely effect change in AHI or AHI response rate.

CONCLUSION

Demonstration of lateral pharyngeal collapse on DISE, in the absence of complete concentric velopharyngeal obstruction, does not appear to adversely affect AHI outcomes in UAS patients.

LEVEL OF EVIDENCE

VI.

Characteristics of Obstructive Sleep Apnea Patients With Hypertension and Factors Associated With Autotitration Acceptance

In order to explore the characteristics and treatment status of obstructive sleep apnea (OSA) patients with hypertension, a retrospective study was conducted on 306 patients admitted from October 2018 to December 2019. According to the apnea hypopnea index (AHI), OSA patients with hypertension were divided into three groups. 69 cases were mild OSA (5 ≤ AHI < 15), 86 cases were moderate (15 ≤ AHI < 30), and 151 cases were severe (AHI ≥ 30). Compared with patients in the mild and moderate groups, the severe group had more male patients, with higher body mass index (BMI) and non-rapid eye movement stage 1 accounted for total sleep time (N1%), and lower non-rapid eye movement stage 2 accounted for total sleep time (N2%), average and minimum blood oxygen. Among all the patients, those who underwent the titration test accounted for 20.6% (63/306). Multivariate analysis showed that sleep efficiency (p < 0.001) and AHI (p < 0.001) were independent factors for patients to accept titration test. OSA patients with hypertension had a low acceptance of titration therapy. These people with higher sleep efficiency and AHI were more likely to receive autotitration.

Mortality analysis of obstructive sleep apnea syndrome cohort receiving positive airway pressure treatment: a 6-year follow-up

OBJECTIVES

Obstructive Sleep apne syndrome is a disease with high morbidity and mortality. The aim of this study was to investigate the conditions affecting the mortality of patients diagnosed with OSAS at six year follow up.

METHODS

970 patients who admitted to Sleep laboratory between 2011-2013 were evaluated retrospectively. 74 patients whose mortality data could not be accessed through the system were excluded. The patients who died until April 2019 were compared with the surviving group in terms of demographic, clinical, comorbidities and polysomnographic findings.

RESULTS

Total 47 patients who died were older, had higher BMI, AHI and ODI values, lower minimum oxygen saturations compared with the survival group (p < .001). In the Cox-hazard regression analysis, BMI (hazard ratio (HR), 1.08; 95% CI, 1.04-1.12), age (1.12, 1.08-1.15), accompanying COPD (2.19, 1.08-4.43), accompanying CAD (2.76, 1.34-5.67) and AHI of >50/h (2.19, 1.19-1.4.05) were reported.

CONCLUSION

This study showed that OSAS increases the risk of death accompanied by CAD and COPD. It has also been shown that patients with higher AHI (AHI > 50/h) values die more. Therefore, it may be useful to classify the AHI> 50/h group as very severe OSAS instead of severe OSAS.

Brainstem lesions are associated with sleep apnea in multiple sclerosis

Background

Studies linking MRI findings in MS patients with obstructive sleep apnea severity are limited.

Objective

We conducted a retrospective study to assess MRI abnormalities associated with obstructive sleep apnea (OSA) in patients with multiple sclerosis (MS).

Methods

We performed retrospective chart review of 65 patients with multiple sclerosis who had undergone polysomnography (PSG) for fatigue as well as brain MRI. We measured the number of lesions in the brainstem and calculated the standardized third ventricular width (sTVW) as a measure of brain atrophy, and subsequently performed correlation analyses of the apnea-hypopnea index (AHI) with brainstem lesion location, sTVW, and Expanded Disability Status Scale (EDSS).

Results

MS Patients with OSA were significantly older and had a higher body mass index (BMI) and higher AHI measures than patients without OSA. After adjustment for covariates, significant associations were found between AHI and lesion burden in the midbrain (p < 0.01) and pons (p = 0.05), but not medulla.

Conclusions

Midbrain and pontine lesions burden correlated with AHI, suggesting MS lesion location could contribute to development of OSA.

Prevalence and Patterns of Obstructive Sleep Apnea in Asian Indians With Congestive Heart Failure

Background Sleep-disordered breathing (SDB) has a potential association with the pathogenesis of congestive heart failure (CHF). We assessed the prevalence and patterns of obstructive sleep apnea (OSA) in patients presenting with CHF. Method This was a prospective, observational, all-comers study of consecutive 77 confirmed cases of CHF. All these patients were clinically assessed and evaluated for OSA with sleep study after routine blood testing, electrocardiogram (ECG), chest X-ray, and echocardiography. Results Of 77 patients with CHF 38 (49.4%) had apnea-hypopnea index (AHI) <5 while 39 (50.6%) had AHI >5. Of these 39, 37 (94.8%) patients showed the clinical features of OSA. The majority (64.9%) of them were males. The majority of OSA (64.9%) had coronary artery disease (CAD) (p<0.05) as the etiology of CHF, followed by dilated cardiomyopathy (32.4%) and valvular heart disease (2.7%). The prevalence of OSA was higher amongst New York Heart Association (NYHA) class 2 (51.4%) as compared to NYHA class 3 (37.8%) and NYHA class 4 (10.8%). There were 12 (32.8%) patients, each having OSA with a heart rate between 71 and 80 bpm and 81 and 90 bpm. Twenty-two (59.5%) had systolic blood pressure (BP) more than 120 mmHg and 20 (54.1%) had diastolic BP more than 80 mmHg. The majority (64.9%) patients had the lowest O2 saturation between 80% and 90%. A significantly large number of patients (62.2%) had ejection fraction 21%-30% (p<0.05). The majority (62.16%) of patients with OSA had AHI between 5 and 15. With 5-15 AHI, 20 (87%) patients with OSA had a snoring, tiredness, observed apnea, high BP, BMI, age, neck circumference, and male gender (STOP-Bang) score between 3 and 7 with AHI 5-15 (p<0.05). Conclusions In our cohort, the prevalence of OSA in CHF was 50.6%. Predictors of OSA in CHF were left ventricular ejection fraction (LVEF) 20%-30% and NYHA class 2. The majority had AHI between 5 and 15. Sleep apnea screening should be routinely implemented in the evaluation and follow-up of heart failure patients.

The STOP-Bang Test Is Useful for Predicting the Severity of Obstructive Sleep Apnea

Introduction:

The STOP-Bang test was used to detect patients at high risk of obstructive sleep apnea (OSA). We evaluated the usefulness of the STOP-Bang test for predicting the severity of OSA in Japanese patients.

Methods:

We retrospectively evaluated the patients who performed full polysomnography at the Mihara Medical Association Hospital. We evaluated the correlation between the STOP-Bang score and the apnea hypopnea index (AHI) using Spearman's rank correlation analysis. We then used multivariate analyses to examine the independent risk factor for severe OSA (AHI ≥ 30/hr).

Results:

One hundred seven patients were diagnosed as no (n = 5), mild (n = 17), moderate (n = 30), and severe (n = 55) OSA. The median age was 67 years old (range: 35-84), and 73 of the 107 patients were males. The correlation coefficient between the STOP-Bang score and AHI was 0.701 (P < 0.001). A STOP-Bang score ≥ 5 had sensitivity of 80.0% and specificity of 76.9% for detecting severe OSA. A STOP-Bang score ≥ 5 and BMI ≥ 30 kg/m² were the independent risk factor for severe OSA.

Conclusions:

The STOP-Bang score correlates with AHI and is useful for predicting OSA severity. Polysomnography should be performed actively for the patients with high STOP-Bang scores.

Targeted Metabolomics Analysis on Obstructive Sleep Apnea Patients after Multilevel Sleep Surgery

BACKGROUND

Obstructive sleep apnea (OSA) is caused by partial or complete obstruction of the upper airways. Corrective surgeries aim at removing obstructions in the nasopharynx, oropharynx, and hypopharynx. OSA is associated with an increased risk of various metabolic diseases. Our objective was to evaluate the effect of surgery on the plasma metabolome.

METHODS

This study included 39 OSA patients who underwent Multilevel Sleep Surgery (MLS). Clinical and anthropometric measures were taken at baseline and five months after surgery.

RESULTS

The mean Apnea-Hypopnea Index (AHI) significantly dropped from 22.0 ± 18.5 events/hour to 8.97 ± 9.57 events/hour (p-Value < 0.001). Epworth's sleepiness Score (ESS) dropped from 12.8 ± 6.23 to 2.95 ± 2.40 (p-Value < 0.001), indicating the success of the surgery in treating OSA. Plasma levels of metabolites, phosphocholines (PC) PC.41.5, PC.42.3, ceremide (Cer) Cer.44.0, and triglyceride (TG) TG.53.6, TG.55.6 and TG.56.8 were decreased (p-Value < 0.05), whereas lysophosphatidylcholines (LPC) 20.0 and PC.39.3 were increased (p-Value < 0.05) after surgery.

CONCLUSION

This study highlights the success of MLS in treating OSA. Treatment of OSA resulted in an improvement of the metabolic status that was characterized by decreased TG, PCs, and Cer metabolites after surgery, indicating that the success of the surgery positively impacted the metabolic status of these patients.

Efficacy of Adenoidectomy for the Treatment of Mild Sleep Apnea in Children

OBJECTIVES

(1) To assess outcomes in children undergoing adenoidectomy for the treatment of mild obstructive sleep apnea (OSA). (2) To identify clinical factors that predict which children will have persistent obstruction following adenoidectomy.

STUDY DESIGN

Case series with chart review over a 10-year period.

SETTING

Tertiary children's hospital.

SUBJECTS AND METHODS

Children between 2 and 17 years old undergoing adenoidectomy for treatment of mild OSA (obstructive apnea-hypopnea index [AHI] between 1 and 5 on polysomnogram) were included. The need for additional medical or surgical intervention following adenoidectomy was recorded. When available, postoperative polysomnogram data were reviewed.

RESULTS

In total, 134 children with a mean age of 5.4 years were included. Fifty-three percent (n = 71) were female and 57% (n = 76) were black. The mean (SD) baseline AHI was 2.2 (1.09). Caregivers reported a moderate impact of sleep disturbance on quality of life with a mean (SD) preoperative total OSA-18 score of 64.1 (19.28). Postadenoidectomy outcomes were reported for 105 patients (78%) with a mean follow-up time of 6 months. Sixty-nine percent (n = 72) of children had resolution of obstructive symptoms. While 31% (n = 33) of children required additional intervention following adenoidectomy, only 6.8% (n = 9) underwent a subsequent tonsillectomy. Demographic factors such as age and baseline AHI did not predict which children required additional treatment following adenoidectomy.

CONCLUSION

Adenoidectomy may be an effective treatment for mild OSA. A randomized trial comparing outcomes for adenoidectomy and adenotonsillectomy is needed to determine the ideal surgical treatment for nonsevere OSA in children.

Factors Affecting Optimal Titration Pressure of Continuous Positive Airway Pressure Device in Patients with Obstructive Sleep Apnea Syndrome

Objective

To assess the effects of anatomical, clinical parameters, and pulmonary respiratory function on the therapeutic titration pressure of continuous positive airway pressure (CPAP) device in obstructive sleep apnea syndrome (OSAS).

Methods

The study comprised 41 OSAS patients whose optimum CPAP titration pressures were measured. Each patient underwent an otorhinolaryngologic and thoracic examination, and data was recorded for height, weight, body mass index, neck-waist circumferences, Mallampati classification, tonsillar hypertrophy, hypopharyngeal collapse, soft palate-tongue base obstruction scores, peak nasal inspiratory flow and acoustic rhinometry measures, and CPAP device therapeutic pressures. Forced vital capacity, forced expiratory volume, FEV1/FVC ratio and peak expiratory flow values were noted.

Results

Median CPAP optimal pressure cut-off value was determined as 9 mmH₂O. Statistical analysis was made in two groups as CPAP titration optimal pressure ≤9 and >9 mmH₂O. In the optimal pressure >9 group, neck and waist circumferences, hypopharyngeal collapse score, retropalatal and retrolingual lateral wall collapse scores were significantly higher (p<0.05). In multivariate and univariate model analysis, neck and waist circumferences, hypopharyngeal collapse score, retropalatal and retrolingual lateral wall collapse scores were observed to be significant in predicting high and low pressures in univariate model.

Conclusion

For the prediction of optimal CPAP titration pressure in OSAS treatment, wide neck and waist circumferences, high hypopharyngeal collapse score and retropalatal and retrolingual lateral wall collapse grades may be determinative.

Obstructive sleep apnea and peripheral vascular disease: a systematic review based on current literature

Introduction

Obstructive sleep apnea (OSA) is an established risk factor for poor cardiovascular outcomes and coronary artery disease, but its influence on the development of peripheral artery disease (PAD) is not well established. The aim of our study was to understand the mutual prevalence of OSA and PAD and any reported statistical association between the two conditions.

Methods

PubMed, Ovid Embase, Web of Science, Cochrane library and clinicaltrials.gov databases were systematically searched up to 29 November 2018. A total of 844 articles were identified and 744 articles were screened for relevance.

Results and Conclusion

Eleven prospective cohorts qualified for inclusion with N = 63,642 (M = 28,062, F = 35,494). All studies evaluated OSA severity primarily with apnea–hypopnea index (AHI) values. The overall prevalence of PAD was 20.5% (N = 13,068). Except for two studies, all studies reported an increased prevalence of OSA in patients with PAD. OSA severity was not found to have an association with poor ankle brachial index values or increasing daytime sleepiness as measured by Epworth sleepiness scale. Further prospective clinical trials are required to further delineate this finding.

Efficacy of Velopharyngeal Surgery for Positional Obstructive Sleep Apnea Hypopnea Syndrome

BACKGROUND

Positional obstructive sleep apnea hypopnea syndrome (P-OSAHS) is a distinct OSAHS type. Whether velopharyngeal surgery is efficacious for patients with P-OSAHS remains unclear.

AIM/OBJECTIVE

To investigate the efficacy and factors influencing velopharyngeal surgery for treatment of patients with P-OSAHS, defined as the apnea hypopnea index (AHI) in different body postures (supine AHI ≥2*nonsupine AHI).

MATERIALS AND METHODS

A total of 44 patients with P-OSAHS who underwent velopharyngeal surgery were retrospectively studied. The clinical data of these patients, including polysomnography (PSG), physical examination, and surgical information, were collected for analysis. All patients underwent a PSG about 6 months after surgery to determine the treatment outcomes.

RESULTS

The overall AHI of the 44 patients decreased from 40.2 ± 18.7 events/h to 18.5 ± 17.5 events/h after surgery (P < .001). There were 29 responders (65.9%) according to the classical definition of surgical success. The percentage of sleep time with oxygen saturation below 90% (CT90) was the only predictive parameter for surgical success (P = .014, odds ratio value = 0.894). There was no significant difference between the change in supine AHI (-55.9 ± 35.2%) and the change in nonsupine AHI (-43.4 ± 74.1%; P = .167), and these 2 parameters were significantly correlated (r = 0.616, P < .001). Among the 38 patients with residual OSAHS (residual AHI ≥5), 28 had persistent P-OSAHS, and the percentage was as high as 82.4%.

CONCLUSIONS AND SIGNIFICANCE

Patients with P-OSAHS with a lower CT90 value are more likely to benefit from velopharyngeal surgery. Positional therapy could be indicated for most of the patients who are not cured by such surgery.

[Correlation between severity of obstructive sleep apnea syndrome and red cell distribution width in elderly patients]

OBJECTIVE

To investigate the correlation between the severity of obstructive sleep apnea syndrome (OSAS) and red cell distribution width (RDW) in elderly patients.

METHODS

A cross-sectional study was conducted among 311 elderly patients diagnosed with OSAS in the snoring clinic between January, 2015 and October, 2016 and 120 healthy controls without OSAS from physical examination populations in the General Hospital of PLA. The subjects were divided into control group with apnea-hypopnea index (AHI) &lt;5 (n=120), mild OSAS group (AHI of 5.0-14.9; n=90), moderate OSAS group (AHI of 15.0-29.9; n=113) and severe OSAS group (AHI ≥ 30; n=108). The clinical characteristics and the results of polysomnography, routine blood tests and biochemical tests of the subjects were collected. Multiple linear regression analysis was used to examine the correlation between OSAS severity and RDW.

RESULTS

The levels of RDW and triglyceride were significantly higher in severe OSAS group than in the other groups (P &lt; 0.01). The levels of fasting blood glucose and body mass index were significantly higher in severe and moderate OSAS groups than in mild OSAS group and control group (P &lt; 0.05 or P &lt; 0.01). Multiple linear regression analysis showed that AHI was positively correlated with body mass index (β=0.111, P=0.032) and RDW (β=0.106, P=0.029). The area under ROC curve of RDW for predicting the severity of OSAS was 0.687 (P=0.0001).

CONCLUSIONS

The RDW increases as OSAS worsens and may serve as a potential marker for evaluating the severity of OSAS.

Complicating effects of obstructive sleep apnea syndrome on the severity of adult asthma

Introduction: Bronchial asthma (BA) and obstructive sleep apnea syndrome (OSAS) are common causes of respiratory disturbance. Many cases of patients with both conditions have been reported, and BA and OSAS may exacerbate each other, but information remains sparse.Methods:We retrospectively evaluated 60 patients under treatment for BA in our department between April 2016 and March 2018 who also underwent portable polysomnography (PSG) for suspected OSAS to assess potential association between PSG results and asthma treatment or respiratory function. BA was diagnosed and treated according to the Asthma Prevention and Management Guideline 2015.Results: We found that BA treatment intensity step was significantly higher for patients with BA who had concurrent moderate or severe OSAS (p = 0.0016). However, neither respiratory function, fraction of exhaled nitric oxide (FeNO), nor forced oscillation technique (FOT) differed significantly between patients with and without OSAS, and apnea hypopnea index was not significantly correlated with respiratory function, FeNO or FOT parameters.Conclusion:We conclude that even though BA patients with OSAS had good respiratory function, their BA was more severe than that of patients without OSAS, suggesting that OSAS may exacerbate BA. Background factors and asthma parameters were not predictive of PSG results, and patients with suspected OSAS should be evaluated proactively by using PSG.

Leptin and adiponectin levels in obstructive sleep apnea phenotypes

Objective: To examine the serum levels of leptin and adiponectin in different obstructive sleep apnea (OSA) phenotypes. Methods: Obese patients who were admitted to our sleep laboratory were included. All patients underwent spirometry, daytime arterial blood gas analysis, polysomnography and transthoracic echocardiography. Serum levels of adiponectin and leptin were recorded. Results: Analysis included 146 OSA patients (81 females, 65 males, age: 49.8 ± 10.7 years, body mass index: 40.3 ± 4.9 kg/m², 47.9% severe OSA, 42.5% severe obesity). Females had higher leptin and adiponectin levels (p < 0.001; p < 0.001, respectively). Leptin levels were higher in patients with severe obesity (p < 0.001). Severe OSA patients had lower leptin and adiponectin levels (p = 0.023; p = 0.035, respectively). Conclusion: Adipokine levels were different especially in OSA patients with severe obesity, female gender and severe OSA.

Upper airway stimulation therapy and sleep architecture in patients with obstructive sleep apnea

OBJECTIVES/HYPOTHESIS

To quantify changes in sleep architecture before and after upper airway stimulation (UAS) therapy in patients with obstructive sleep apnea.

STUDY DESIGN

Retrospective chart review.

METHODS

This study was performed at a single-institution tertiary academic care center. Patients who responded successfully to UAS implantation were selected for this study. Preoperative and postoperative sleep studies were compared to determine sleep architecture changes. Primary outcomes included sleep architecture parameters such as N1, N2, N3, and rapid eye movement (REM) in addition to others. Secondary outcomes included body mass index.

RESULTS

Thirty-five patients met inclusion criteria for this study. There was significant improvement across several sleep architecture parameters. N1 sleep percent decreased from 16.7% ± 2.1% preoperatively to 10.1% ± 1.6% postoperatively (P = .023). Time spent in N2 increased from 148.0 ± 12.4 minutes to 185.5 ± 10.4 minutes (P = .030), whereas N3 increased from 21.9 ± 5.0 minutes to 57.0 ± 11.1 minutes (P = .013). No significant changes were observed in REM sleep. Arousal index decreased from 38.8 ± 4.0 to 30.3 ± 4.0 (P = .050).

CONCLUSIONS

There was significant improvement across several sleep architecture parameters among patients who responded successfully to UAS implantation.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:1085-1089, 2020.

Targeted sequencing analysis of the adiponectin gene identifies variants associated with obstructive sleep apnoea in Chinese Han population

Obstructive sleep apnoea (OSA) is a prevalent sleep disorder considered as an independent risk factor for cardiovascular consequences. It has a strong genetic background and is associated with hypoadiponectinaemia.Target sequencing of whole ADIPONQ gene was performed in 340 participants including 247 patients with OSA and 93 non-OSA participants. Polysomnography was used to diagnose OSA. The associations between variants and OSA were determined by multivariate regression analysis.Thirteen single nucleotide polymorphisms of ADIPOQ were identified in all subjects. Genotype frequencies at rs4686803 (P = .034), rs3774262 (P = .034), and rs2082940 (P = .045) were significantly different between OSA and non-OSA groups. Individuals carrying the CT/TT genotypes of rs4686803, GA/AA genotypes of rs3774262, and CT/TT genotypes of rs1063537 were associated with 2.295-, 2.295- and 2.155-fold increased risk of OSA respectively in dominant model, after adjusting for confounding effects. The subjects with the rs2082940 CC genotype were associated with decreased risk of OSA (OR: 0.455) in recessive model. Additionally, the apnoea-hypopnea index (AHI) was significantly increased in rs3774262 (GA/AA) (P = .001), rs4686803 (CT/TT) (P = .001), and rs1063537 (CT/TT) (P = .004) genotype individuals than those with rs3774262 (GG), rs4686803 (CC), and rs1063537 (CC) genotypes, respectively. The AHI was significantly decreased in individuals with ADIPOQ rs2082940 CC genotypes than in those with the CT and TT genotype (P = .007). Moreover, the stratified analysis found that the genotype of rs3774262 (GA/AA), rs4686803 (CT/TT), and rs1063537 (CT/TT) variants were associated with increased risk of OSA by 2.935-, 2.935- and 2.786-fold in overweight participants. The genotype of rs2082940 CC variants was associated with decreased risk of OSA (OR: 0.373) in overweight participants compared with rs2082940 CT/ TT genotypes.ADIPOQ variants rs3774262, rs4686803, rs1063537, and rs2082940 were associated with the prevalence of OSA in Chinese Han individuals.

[Relationship between upper airway volume and polysomnography parameters of patients with obstructive sleep apnea hypopnea syndrome]

Objective:To study the relationship among upper airway volume of naso-pharyngeal, yelo-pharyngeal,glosso-pharyngeal, hypo-pharyngeal area which measured by spiral computed tomography three-dimensional reconstruction technique, apnea hypopnea indexes, and the lowest oxygen saturation in patients with OSAHS.Method:①fifty-one patients with OSAHS were received polysomnography, and then were divided into groups by the AHI,LSaO₂ values. ②To measure upper airway volume at normal breath and Müller maneuver state using spiral computed tomography three-dimensional reconstruction technique of CT measurement, and to calculate volume change rate and observe the upper airway compliance. ③To analyses the relationship between upper airway volume and AHI,LSaO₂ values.Result:The smallest upper airway volume of OSAHS was at the velo-pharyngeal level; the volume of velo-pharyngeal level were negatively correlated with AHI during normal respiration and Müller's maneuver state and were positively correlated with LSaO₂; the volume of hypo-pharyngeal were negatively correlated with AHI during normal respiration; the volume of glosso-pharyngeal were positively correlated with LSaO₂ during Müller's maneuver state.Conclusion:①The volume of velo-pharyngeal level with OSAHS patients can reflect the severity of AHI,LSaO₂. ②The measurement of upper airway volume using spiral computed tomography three-dimensional reconstruction technique is good method to evaluate the upper airway compliance of OSAHS patients.

Association of allergic rhinitis with obstructive sleep apnea: A meta-analysis

BACKGROUND

The co-existence of allergic rhinitis (AR) and obstructive sleep apnea (OSA) is a common phenomenon in clinical practice. AR has long been considered a risk factor for OSA. However, the relationship is not completely clear. Therefore, we conducted a meta-analysis to evaluate the prevalence of AR in sleep-disordered breathing (SDB) /OSA and their relationship.

METHODS

A comprehensive literature search was performed in PubMed/Medline, Google Scholar, Wiley Online Library, EMBASE, and Web of Science. Data were analyzed and pooled to estimate effect size (ES) /odds ratio (OR) with 95% confidence intervals (95%CI). Heterogeneity was quantified and evaluated by chi-squared-based Q-test and I2 test, with P < .05 and I > 50% indicating evidence of heterogeneity.

RESULTS

44 studies contained 6086 participants were included in this meta-analysis. For adults, the prevalence of AR was 22.8 (95% CI, 15.0-30.6) % in SDB and 35.2 (95% CI, 25.6-44.7) % in OSA. In children with SDB and OSA, the prevalence of AR was 40.8 (95% CI, 24.3-57.2) %, and 45.2 (95% CI, 25.4-65.0) % respectively. The odds ratios of prevalence of the SDB pediatric patients with AR was 2.12 (95%CI, 1.75, 2.57; P < .0001) times higher than that of non-SDB pediatric patients. There were no significant differences between OSA adults with or without AR in BMI (Body Mass Index), neck circumference, apnea hypopnea index (AHI) and epworth sleep scale score (ESS).

CONCLUSION

The prevalence of AR in OSA/SDB is considerably high and children with SDB suffering from a higher incidence of AR than non-SDB. OSA adults accompanied with AR do not have any influences on sleep parameters.

Comparison of radiofrequency and transoral robotic surgery in obstructive sleep apnea syndrome treatment

INTRODUCTION

Radiofrequency tissue ablation (RFTA) and transoral robotic surgery (TORS) are the methods used in OSAS surgery. We also aimed to compare the advantages and disadvantages of RF and TORS as treatment methods applied in OSAS patients in terms of many parameters, especially apnea hypopnea index (AHI).

MATERIALS AND METHODS

Patients were classified by performing a detailed examination and evaluation before surgery. 20 patients treated with anterior palatoplasty and uvulectomy -/+ tonsillectomy + RFTA (17 males, 3 females) and 20 patients treated with anterior palatoplasty and uvulectomy -/+  tonsillectomy + TORS (16 males, 4 females) were included in the study. PSG was performed preoperatively and postoperatively in all patients and Epworth sleepiness questionnaire was applied. All operations were performed by the same surgeon and these surgical methods -RF and TORS- were compared in terms of many parameters.

RESULTS

When the patients treated with RF and TORS were compared in operation time, length of hospitalization and duration of transition to oral feeding; all parameters were significantly greater in the patients treated with TORS.

CONCLUSIONS

TORS technique was found to be more successful than RF in terms of reduction of AHI value, correcting minimum arterial oxygen saturation value and decreasing Epworth Sleepiness Scale score.

Increased Level of Angiopoietin Like Proteins 4 and 8 in People With Sleep Apnea

Objective: Obstructive sleep apnea (OSA) is a sleep disorder caused by the complete or partial obstruction of the upper airways. The worldwide prevalence of OSA is increasing due to its close association with obesity epidemic and multiple health complications, such as hypertension, cardiovascular disease, and Type 2 diabetes. Angiopoietin-like protein (ANGPTL)-4 and ANGPTL8 (betatrophin) have been suggested to play a role in the development of these diseases through their role in regulating the metabolism of plasma lipid molecules. This study was designed to evaluate ANGPTL4 and 8 levels in an OSA group and a control group to clarify the effect of OSA on ANGPTL4 and 8 levels. Methods: In total, 74 subjects were enrolled in this study, including 22 age- and body mass index (BMI)-matched controls with the Apnea Hypopnea Index (AHI) score of <5 events/h and 52 subjects with an AHI score of >5 events/h. Sleep apnea was assessed using a portable sleep test. ANGPTL4 and 8 levels were measured in plasma samples using enzyme-linked immunosorbent assay. Results: Mean AHI score (2.5 ± 1.6) in the control group was significantly lower than that in the OSA group (22.9 ± 17.9; p < 0.0001). Leptin, interleukin-(IL) 6, insulin, and HOMA-IR values were higher in the OSA group than in the control group. ANGPTL8 level was higher in the OSA group (1130.0 ± 108.61 pg/mL) than in the control group (809.39 ± 108.78 pg/mL; p = 0.041). Similarly, ANGPTL4 was higher in the OSA group (179.26 ± 12.89 ng/mL) than in the control group (142.63 ±7.99 ng/mL; p = 0.018). Conclusion: Our findings demonstrate that ANGPTL4 and 8 levels were increased in subjects with OSA, suggesting that the upregulation of these lipid metabolism regulators might play a role in lipid dysregulation observed in people with OSA.

Therapeutic effects of different drugs on obstructive sleep apnea/hypopnea syndrome in children

BACKGROUND

This study aimed to compare the therapeutic effects of different drugs on obstructive sleep apnea/hypopnea syndrome (OSAHS) in children by using a network meta-analysis approach.

METHODS

PubMed, Embase and Cochrane Library were searched from the inception of each database to November 2015. Randomized controlled trials (RCTs) concerning the comparisons in the therapeutic effects of eight placebo-controlled drugs on OSAHS in children were included in this study. Network meta-analysis combined direct evidence and indirect evidence to evaluate the weighted mean difference (WMD) and surface under the cumulative ranking curves (SUCRA) of therapeutic effects of eight drugs on OSAHS in children.

RESULTS

A total of seven RCTs were finally incorporated into our network meta-analysis. Pairwise meta-analysis results revealed that therapeutic effect of placebo was significantly poorer than that of intranasal mometasone furoate, montelukast, budesonide and fluticasone concerning apnea hypopnea index (AHI) value [WMD=1.40, 95% confidence interval (CI)=1.17-1.63; WMD=2.80, 95% CI=1.01-4.59; WMD=3.50, 95% CI=3.34-3.66; WMD=7.20, 95% CI=5.26-9.14, respectively], and fluticasone is better than placebo concerning sleep efficiency (WMD=3.50, 95% CI=2.42-4.58); regarding visual analogue scale, the therapeutic effect of placebo was poorer compared with sucralfate and clindamycin (WMD=1.94, 95% CI=1.13-2.75; WMD=1.06, 95% CI=0.22-1.90), and sucralfate is better than clindamycin (WMD=-0.88, 95% CI=-1.65 to -0.11). However, network meta-analysis results showed no obvious difference in the therapeutic effects of different drugs on OSAHS regarding AHI and sleep efficiency. Furthermore, the best SUCRA value was very high for fluticasone concerning AHI (86.6%) and budesonide concerning sleep efficiency (94.0%) for OSAHS treatment.

CONCLUSIONS

Fluticasone and budesonide have relatively good effects in the treatment of OSAHS in children, thus providing an important guiding significance for the treatment of OSAHS in children.

Is There a Link Between Obstructive Sleep Apnea Syndrome and Fibromyalgia Syndrome?

OBJECTIVES

Fibromyalgia syndrome (FMS) is characterized by complaints of chronic musculoskeletal pain, fatigue, and difficulty in falling asleep. Obstructive sleep apnea syndrome (OSAS) is associated with symptoms, such as morning fatigueness and unrefreshing sleep. We aimed to investigate the presence of OSAS and objectively demonstrate changes in sleep pattern in patients with FMS.

MATERIAL AND METHODS

Polysomnographic investigations were performed on 24 patients with FMS. Patients were divided into two groups: patients with and without OSAS (Group 1 and Group 2, respectively). A total of 40 patients without FMS who presented to the sleep disorders polyclinic with an initial diagnosis of OSAS were included in Group 3. Based on their apnea hypopnea index (AHI), OSAS in the patients were categorized as mild (AHI, 5-15), moderate (30), or severe (>30).

RESULTS

OSAS was detected in 50% of patients with FMS. The most prominent clinical findings were morning fatigue and sleep disorder, which were similar in three groups. In polysomnography (PSG) evaluation, patients with FMS had mild (33%), moderate (25%), and severe (42%) OSAS. In correlation analyses, negative correlations were observed between fibromyalgia impact questionnaire (FIQ) and mean oxygen saturation, visual analogue scale (VAS), and minimum oxygen saturation, whereas a positive correlation was found between FIQ and desaturation times in patients with FMS.

CONCLUSION

Detection of OSAS in 50% of the patients with FMS, and similar rates of complaints of sleep disorder and morning fatigue of OSAS and FMS cases are important results. Detection of correlation between the severity of hypoxemia and FIQ and VAS scores are significant because it signifies the contribution of increased tissue hypoxemia to the deterioration of clinical status. Diagnosis and treatment of OSAS associated with FMS are important because of their favorable contributions to the improvement of the clinical picture of FMS.

Upper Airway Stimulation for Obstructive Sleep Apnea: Patient-Reported Outcomes after 48 Months of Follow-up

Objective To assess patient-based outcomes of participants in a large cohort study-the STAR trial (Stimulation Therapy for Apnea Reduction)-48 months after implantation with an upper airway stimulation system for moderate to severe obstructive sleep apnea. Study Design A multicenter prospective cohort study. Setting Industry-supported multicenter academic and clinical setting. Subjects Participants (n = 91) at 48 months from a cohort of 126 implanted participants. Methods A total of 126 participants received an implanted upper airway stimulation system in a prospective phase III trial. Patient-reported outcomes at 48 months, including Epworth Sleepiness Scale (ESS), Functional Outcomes of Sleep Questionnaire (FOSQ), and snoring level, were compared with preimplantation baseline. Results A total of 91 subjects completed the 48-month visit. Daytime sleepiness as measured by ESS was significantly reduced ( P = .01), and sleep-related quality of life as measured by FOSQ significantly improved ( P = .01) when compared with baseline. Soft to no snoring was reported by 85% of bed partners. Two patients required additional surgery without complication for lead malfunction. Conclusion Upper airway stimulation maintained a sustained benefit on patient-reported outcomes (ESS, FOSQ, snoring) at 48 months in select patients with moderate to severe obstructive sleep apnea.

Effective Apnea-Hypopnea Index ("Effective AHI"): A New Measure of Effectiveness for Positive Airway Pressure Therapy

STUDY OBJECTIVES

To assess a new measure of positive airway pressure (PAP) effectiveness, the Effective AHI, which accounts for sleep disordered breathing events during the time PAP is (PAP On) and is not (PAP Off) being used. A secondary aim was to test the accuracy of the Watch-PAT 200 (WP) portable monitor for measurement of the Effective AHI.

METHODS

A prospective two-center cohort study design was used to evaluate patients who had been prescribed PAP therapy for ≥ 2 months. The primary outcome measure was the Effective AHI as determined by an in-laboratory polysomnogram (PSG) where patients used their PAP machine as they did at home, and concomitantly wore the WP. The Effective AHI equals the sum of apneas and hypopneas with PAP On and PAP Off divided by hours of total sleep time.

RESULTS

Twenty-eight adult patients (75% men, age 51.4 ± 10.8 years [mean ± SD]) comprised the study sample. The mean Effective AHI of 18.3, was significantly lower than the mean Diagnostic AHI of 67.9 (P < 0.0001). All patients using PAP ≥ 6 h had an Effective AHI < 5. For patients using PAP < 6 h, Effective AHI scores < 5 only occurred in patients who slept in a non-supine position during PAP Off time; leaving 63.6% of patients with residual moderate-to-severe OSA. There was a high correlation between the PSG and WP for the Effective AHI (r = 0.871).

CONCLUSIONS

Significant disease burden, as objectively measured by the Effective AHI, may still exist in many patients with severe OSA in whom PAP therapy is not utilized for the entire sleep period. The WP is a reasonably accurate device to measure the Effective AHI.

Reduction of internal carotid artery intima-media thickness in patients with moderate-to-severe obstructive sleep apnea syndrome after nasal surgery and uvulopalatopharyngoplasty

CONCLUSION

Multi-level surgeries for the nasal cavity and palate can reduce the severity of obstructive sleep apnea with major narrowing above the retropalatal airway and reduce the carotid intima-media thickness, which can provide cardiovascular benefits to patients.

OBJECTIVE

To evaluate the outcomes of moderate-to-severe obstructive sleep apnea syndrome by surgeries and the change of internal carotid artery intima-media thickness after surgeries.

SUBJECTS AND METHODS

Sixty-four patients with obstructive sleep apnea, narrowing at the nasal cavity, and retropalatal airways were enrolled in this study. Fifty-two patients underwent nasal surgery and modified uvulopalatopharyngoplasty. Twelve patients who refused surgeries and continuous positive airway pressure treatment received only conservative treatment. All patients were evaluated within 1 month before and 6 months after treatment using polysomnography, upper airway endoscopy, and B mode ultrasound.

RESULTS

The success rate was 61.5% (32/52 patients) in the surgery group. There were significant differences between the surgery group and non-surgery group 6 months after treatment in the apnea hypopnea index, minimum and mean oxygen saturation, blood pressure, triglyceride, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and internal Carotid intima-media thickness. The changes in the oxygen saturation and the apnea hypopnea index showed significant correlations with the changes in the intima-media thickness.

Overweight explains the increased red blood cell aggregation in patients with obstructive sleep apnea

Sleep apnea patients and obese subjects are overexposed to cardiovascular diseases. These two health conditions may be associated with hemorheological alterations which could increase the cardiovascular risk. The present study investigated the hemorheological characteristics in patients with overweight and/or sleep apnea to identify the main predictor of red blood cell (RBC) abnormalities in sleep apnea patients. Ninety-seven patients were subjected to one night sleep polygraphy to determine their sleep apnea status. Body mass index (BMI) and the apnea/hypopnea index (AHI) were determined for categorization of obesity and sleep apnea status. Blood was sampled for hematocrit, blood viscosity, RBC deformability, aggregation and disaggregation threshold measurements. BMI and AHI were positively associated and were both positively associated with RBC aggregation. Analyses of covariance and multiple regression analyses revealed that BMI was more predictive of RBC aggregation than AHI. No association of BMI classes and AHI classes with RBC deformability or blood viscosity was observed. This study shows that increased RBC aggregation in sleep apnea patients is caused by overweight. Therapies to improve blood rheology in sleep apnea patients, and therefore reduce the risk for cardiovascular disorders, should focus on weight-loss.

Three-Year Outcomes of Cranial Nerve Stimulation for Obstructive Sleep Apnea: The STAR Trial

OBJECTIVE

To describe the 36-month clinical and polysomnography (PSG) outcomes in an obstructive sleep apnea (OSA) cohort treated with hypoglossal cranial nerve upper airway stimulation (UAS).

STUDY DESIGN

A multicenter prospective cohort study.

SETTING

Industry-supported multicenter academic and clinical setting.

SUBJECTS

Participants (n = 116) at 36 months from a cohort of 126 implanted participants.

METHODS

Participants were enrolled in a prospective phase III trial evaluating the efficacy of UAS for moderated to severe OSA. Prospective outcomes included apnea-hypopnea index, oxygen desaturation index, other PSG measures, self-reported measures of sleepiness, sleep-related quality of life, and snoring.

RESULTS

Of 126 enrolled participants, 116 (92%) completed 36-month follow-up evaluation per protocol; 98 participants additionally agreed to a voluntary 36-month PSG. Self-report daily device usage was 81%. In the PSG group, 74% met the a priori definition of success with the primary outcomes of apnea-hypopnea index, reduced from the median value of 28.2 events per hour at baseline to 8.7 and 6.2 at 12 and 36 months, respectively. Similarly, self-reported outcomes improved from baseline to 12 months and were maintained at 36 months. Soft or no snoring reported by bed partner increased from 17% at baseline to 80% at 36 months. Serious device-related adverse events were rare, with 1 elective device explantation from 12 to 36 months.

CONCLUSION

Long-term 3-year improvements in objective respiratory and subjective quality-of-life outcome measures are maintained. Adverse events are uncommon. UAS is a successful and appropriate long-term treatment for individuals with moderate to severe OSA.

The Circadian System Contributes to Apnea Lengthening across the Night in Obstructive Sleep Apnea

STUDY OBJECTIVE

To test the hypothesis that respiratory event duration exhibits an endogenous circadian rhythm.

DESIGN

Within-subject and between-subjects.

SETTINGS

Inpatient intensive physiologic monitoring unit at the Brigham and Women's Hospital.

PARTICIPANTS

Seven subjects with moderate/severe sleep apnea and four controls, age 48 (SD = 12) years, 7 males.

INTERVENTIONS

Subjects completed a 5-day inpatient protocol in dim light. Polysomnography was recorded during an initial control 8-h night scheduled at the usual sleep time, then through 10 recurrent cycles of 2 h 40 min sleep and 2 h 40 min wake evenly distributed across all circadian phases, and finally during another 8-h control sleep period.

MEASUREMENTS AND RESULTS

Event durations, desaturations, and apnea-hypopnea index for each sleep opportunity were assessed according to circadian phase (derived from salivary melatonin), time into sleep, and sleep stage. Average respiratory event durations in NREM sleep significantly lengthened across both control nights (21.9 to 28.2 sec and 23.7 to 30.2 sec, respectively). During the circadian protocol, event duration in NREM increased across the circadian phases that corresponded to the usual sleep period, accounting for > 50% of the increase across normal 8-h control nights. AHI and desaturations were also rhythmic: AHI was highest in the biological day while desaturations were greatest in the biological night.

CONCLUSIONS

The endogenous circadian system plays an important role in the prolongation of respiratory events across the night, and might provide a novel therapeutic target for modulating sleep apnea.

Sole effect of genioglossus advancement on apnea hypopnea index of patients with obstructive sleep apnea

CONCLUSION

Selected patients might have benefited from genioglossus advancement (GA), even it was applied solely. GA provided significant reduction on the apnea hypopnea index (AHI), with a 53% surgical success.

OBJECTIVES

The aim of this study was to evaluate the impact of GA on AHI of patients with obstructive sleep apnea (OSA).

METHOD

From January 2008 to April 2014 patients who underwent a genioglossus advancement procedure alone were included into the study and records of these cases were analyzed retrospectively. Pre-operative and post-operative values of body mass index (BMI), Epworth Sleepiness Scale (ESS), nocturnal polysomnographic data including AHI, mean, and minimum oxygen saturation were compared.

RESULTS

There were 16 males and one female patient with the mean age of 46 years. The AHI showed a significant reduction from 27.5 ± 8 pre-operatively to 17.3 ± 12.6 post-operatively. The pre-operative and post-operative mean O2 saturation value improved from 92.1 ± 2.4% to 93.4 ± 1.7%. Pre-operative ESS scores decreased significantly from 7.7 ± 1.6 to 4.8 ± 1.9. There were no significant difference between pre- and post-operative values of BMI and minimum O2 saturation. The success rate was found to be 53%, which was based on success criteria as an AHI of <20 with at least 50% reduction.

Utility of symptoms to predict treatment outcomes in obstructive sleep apnea syndrome

BACKGROUND AND OBJECTIVES

Polysomnography defines the pathophysiology of obstructive sleep apnea syndrome (OSAS) but does not predict some important comorbidities or their response to adenotonsillectomy. We assessed whether OSAS symptoms, as reflected on the Sleep-Related Breathing Disorders Scale of the Pediatric Sleep Questionnaire (PSQ), may offer clinical predictive value.

METHODS

Baseline and 7-month follow-up data were analyzed from 185 participants (aged 5-9 years with polysomnographically confirmed OSAS) in the surgical treatment arm of the multicenter Childhood Adenotonsillectomy Trial. Associations were assessed between baseline PSQ or polysomnographic data and baseline morbidity (executive dysfunction, behavior, quality of life, sleepiness) or postsurgical improvement.

RESULTS

At baseline, each 1-SD increase in baseline PSQ score was associated with an adjusted odds ratio that was ∼3 to 4 times higher for behavioral morbidity, 2 times higher for reduced global quality of life, 6 times higher for reduced disease-specific quality of life, and 2 times higher for sleepiness. Higher baseline PSQ scores (greater symptom burden) also predicted postsurgical improvement in parent ratings of executive functioning, behavior, quality of life, and sleepiness. In contrast, baseline polysomnographic data did not independently predict these morbidities or their postsurgical improvement. Neither PSQ nor polysomnographic data were associated with objectively assessed executive dysfunction or improvement at follow-up.

CONCLUSIONS

PSQ symptom items, in contrast to polysomnographic results, reflect subjective measures of OSAS-related impairment of behavior, quality of life, and sleepiness and predict their improvement after adenotonsillectomy. Although objective polysomnography is needed to diagnose OSAS, the symptoms obtained during an office visit can offer adjunctive insight into important comorbidities and likely surgical responses.

Vibration signals of snoring as a simple severity predictor for obstructive sleep apnea

BACKGROUND AND AIM

Polysomnography (PSG), which involves simultaneous monitoring of various physiological monitors, is the current comprehensive tool for diagnosing obstructive sleep apnea (OSA). We aimed at validating vibrating signals of snoring as a single physiological parameter for screening and evaluating severity of OSA.

METHODS

Totally, 111 subjects from the sleep center of a tertiary referral center were categorized into four groups according to the apnea hypopnea index (AHI) obtained from PSG: simple snoring group (5 > AHI, healthy subjects, n = 11), mild OSA group (5 ≤ AHI < 15, n = 11), moderate OSA group (15 ≤ AHI < 30, n = 30) and severe OSA group (AHI ≥ 30, n = 59). Anthropometric parameters and sleep efficiency of all subjects were compared. Frequencies of amplitude changes of vibrating signals on anterior neck during sleep were analyzed to acquire a snoring burst index (SBI) using a novel algorithm. Data were compared with AHI and index of arterial oxygen saturation (Δ Index).

RESULTS

There were no significant differences in age and sleep efficiency among all groups. Bland-Altman analysis showed better agreement between SBI and AHI (r = 0.906, P < 0.001) than Δ Index and AHI (r = 0.859, P < 0.001). Additionally, receiver operating characteristic (ROC) showed substantially stronger sensitivity and specificity of SBI in distinguishing between patients with moderate and severe OSA compared with Δ Index (sensitivity: 81.4% vs 66.4%; specificity: 96.7% vs 86.7%, for SBI and Δ Index, respectively).

CONCLUSION

SBI may serve as a portable tool for screening patients and assessing OSA severity in a non-hospital setting.

The impact of recent changes to the respiratory scoring rules in pediatrics

STUDY OBJECTIVES

In 2007 the American Academy of Sleep Medicine (AASM) published polysomnography (PSG) scoring guidelines, which were updated in 2012. A key change in terms of scoring respiratory events in children was the threshold for reduction in airflow (50% vs 30%) for the definition of hypopnea. This study aimed to determine the impact of different scoring rules on the assessment of severity of obstructive sleep apnea (OSA) in children.

METHODS

Forty-two children (mean age 4.3 y, 16 F) underwent PSG. An obstructive apnea-hypopnea index (OAHI) was determined using three scoring rules: (1) ATS 1996 rules with minor modifications (modified ATS 1996); (2) AASM 2007 rules (AASM 2007); and (3) AASM 2007 rules with respiratory event related arousals included in the OAHI (AASM+RERA).

RESULTS

The AASM 2007 OAHI (median 0.4 events/h, range 0, 14) was lower than the modified ATS 1996 OAHI (median 0.8 range 0, 26.1, p < 0.001), underestimating severity of disease in 24% of cases. The AASM+RERA OAHI (median 0.8, range 0, 19.1) was also lower than the modified ATS 1996 OAHI (p = 0.02), but the difference was not clinically significant except at very high OAHIs.

CONCLUSION

The AASM 2007 rules lead to a lower OAHI and lesser OSA severity when compared to the previous standard. Inclusion of RERAs in the AASM 2007 OAHI leads to a comparable OAHI to the previous rules. Given that morbidity has been demonstrated even in mild OSA, these results support the inclusion of events with a reduction in airflow of less than 50% as included in the updated AASM rules in 2012.

A 2-year mean follow-up of oral appliance therapy for severe obstructive sleep apnea: a cohort study

OBJECTIVE

Oral appliances for treating severe obstructive sleep apnea (OSA) are recommended for patients who failed to comply with continuous positive airway pressure (CPAP) treatment. The objective of this study was to evaluate medium long-term outcome and success rates of oral appliances in patients with severe OSA.

METHODS

In a retrospective study, 52 OSA patients with an apnea-hypopnea index (AHI) ≥40, who did not tolerate CPAP treatment, were enrolled and fitted with a modified Herbst oral appliance. A 2-year mean follow-up including a second somnography was conducted in 36 of the patients.

RESULTS

A significant reduction (P < 0.0001) in the AHI was demonstrated between the initial somnography (55.25 ± 10.79,) and the followed one (17.74 ± 11.0, n = 36). Overall, 57.7% of total study subjects (n = 52) and 63.9% (n = 36) that had sequential sonmogarphy continued using the device. The reduction in AHI in the user group was 42.4 ± 3.1 (n = 23), which was significantly higher (P = 0.013) than in the non-user group (28.9 ± 17.2; n = 13). Moreover, 53% (n = 19) reached AHI of <15.

CONCLUSIONS

Oral appliances were found to be successful for treating for severe OSA after first-line treatment had failed.

Predictors of obstructive sleep apnea severity in adenotonsillectomy candidates

STUDY OBJECTIVES

There is uncertainty over which characteristics increase obstructive sleep apnea syndrome (OSAS) severity in children. In candidates for adenotonsillectomy (AT), we evaluated the relationship of OSAS severity and age, sex, race, body mass index (BMI), environmental tobacco smoke (ETS), prematurity, socioeconomic variables, and comorbidities.

DESIGN

Cross-sectional screening and baseline data were analyzed from the Childhood Adenotonsillectomy Trial, a randomized, controlled, multicenter study evaluating AT versus medical management. Regression analysis assessed the relationship between the apnea hypopnea index (AHI) and risk factors obtained by direct measurement or questionnaire.

SETTING

Clinical referral setting.

PARTICIPANTS

Children, ages 5 to 9.9 y with OSAS.

MEASUREMENTS AND RESULTS

Of the 1,244 children undergoing screening polysomnography, 464 (37%) were eligible (2 ≤ AHI < 30 or 1 ≤ obstructive apnea index [OAI] < 20 and without severe oxygen desaturation) and randomized; 129 (10%) were eligible but were not randomized; 608 (49%) had AHI/OAI levels below entry criteria; and 43 (3%) had levels of OSAS that exceeded entry criteria. Among the randomized children, univariate analyses showed significant associations of AHI with race, BMI z score, environmental tobacco smoke (ETS), family income, and referral source, but not with other variables. After adjusting for potential confounders, African American race (P = 0.003) and ETS (P = 0.026) were each associated with an approximately 20% increase in AHI. After adjusting for these factors, obesity and other factors were not significant.

CONCLUSIONS

Apnea hypopnea index level was significantly associated with race and environmental tobacco smoke, highlighting the potential effect of environmental factors, and possibly genetic factors, on pediatric obstructive sleep apnea syndrome severity. Efforts to reduce environmental tobacco smoke exposure may help reduce obstructive sleep apnea syndrome severity.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov (#NCT00560859).

Advanced age and apnea-hypopnea index predict subclinical atherosclerosis in patients with obstructive sleep apnea syndrome

BACKGROUND

Both obstructive sleep apnea syndrome (OSAS) and coronary artery calcification (CAC) are considered to be related with the presence of coronary artery disease (CAD). In this study we evaluate the association between OSAS and presence of subclinical atherosclerosis assessed by tomographic coronary calcium score in patients who had OSAS but no history of known CAD.

METHODS

Seventy-three patients who were asymptomatic for CAD and had suspected OSAS were referred to overnight attended polysomnography. Patients were classified into 4 groups according to the Apnea-Hypopnea Index (AHI). All patients underwent computed tomographic examination for tomographic coronary calcification scoring. Physical examination, sleep study recordings, complete blood count and serum biochemistry were obtained from all patients.

RESULTS

In the whole group, AHI levels were weakly correlated with coronary calcium score (r = 0.342, p = 0.003) and body mass index (r = 0.337, p = 0.004), moderately correlated with basal oxygen saturation (r = -0.734, p < 0.001), and strongly correlated with oxygen desaturation index (r = 0.844, p < 0.001). In an univariate analysis, age, AHI, basal oxygen saturation, and oxygen desaturation index were associated with CAC in patients with OSAS. In a multiple logistic regression model, age (OR 1.108,%95 CI 1.031-1.191, p = 0.005) and AHI (OR 1.036,% 95 CI 1.003-1.070, p = 0.033) were only independent predictors of CAC in patients with OSAS with a sensitivity of 88.9% and 77.8% and a specificity of 54.3% and 56.5% respectively.

CONCLUSIONS

Our findings suggest that in patients with moderate or severe OSAS and advanced age, physicians should be alert for the presence of subclinical atherosclerosis.

Obstructive sleep apnea

Obstructive sleep apnea (OSA) affects millions of Americans and is estimated to be as prevalent as asthma and diabetes. Given the fact that obesity is a major risk factor for OSA, and given the current global rise in obesity, the prevalence of OSA will increase in the future. Individuals with sleep apnea are often unaware of their sleep disorder. It is usually first recognized as a problem by family members who witness the apneic episodes or is suspected by their primary care doctor because of the individual's risk factors and symptoms. The vast majority remain undiagnosed and untreated, despite the fact that this serious disorder can have significant consequences. Individuals with untreated OSA can stop breathing hundreds of times a night during their sleep. These apneic events can lead to fragmented sleep that is of poor quality, as the brain arouses briefly in order for the body to resume breathing. Untreated, sleep apnea can have dire health consequences and can increase the risk of hypertension, diabetes, heart disease, and heart failure. OSA management has also become important in a number of comorbid neurological conditions, including epilepsy, stroke, multiple sclerosis, and headache. Diagnosis typically involves use of screening questionnaires, physical exam, and an overnight polysomnography or a portable home study. Treatment options include changes in lifestyle, positive airway pressure, surgery, and dental appliances.