Causal role of immune cells in obstructive sleep apnea hypopnea syndrome:Mendelian randomization study

BACKGROUND Despite being one of the most prevalent sleep disorders,obstructive sleep apnea hypoventilation syndrome(OSAHS)has limited information on its immunologic foundation.The immunological underpinnings of certain major psychiatric diseases have been uncovered in recent years thanks to the extensive use of genome-wide association studies(GWAS)and genotyping techniques using highdensity genetic markers(e.g.,SNP or CNVs).But this tactic hasn't yet been applied to OSAHS.Using a Mendelian randomization analysis,we analyzed the causal link between immune cells and the illness in order to comprehend the immunological bases of OSAHS.AIM To investigate the immune cells'association with OSAHS via genetic methods,guiding future clinical research.METHODS A comprehensive two-sample mendelian randomization study was conducted to investigate the causal relationship between immune cell characteristics and OSAHS.Summary statistics for each immune cell feature were obtained from the GWAS catalog.Information on 731 immune cell properties,such as morphologic parameters,median fluorescence intensity,absolute cellular,and relative cellular,was compiled using publicly available genetic databases.The results'robustness,heterogeneity,and horizontal pleiotropy were confirmed using extensive sensitivity examination.RESULTS Following false discovery rate(FDR)correction,no statistically significant effect of OSAHS on immunophenotypes was observed.However,two lymphocyte subsets were found to have a significant association with the risk of OSAHS:Basophil%CD33dim HLA DR-CD66b-(OR=1.03,95%CI=1.01-1.03,P<0.001);CD38 on IgD+CD24-B cell(OR=1.04,95%CI=1.02-1.04,P=0.019).CONCLUSION This study shows a strong link between immune cells and OSAHS through a gene approach,thus offering direction for potential future medical research.

Cognitive and Emotional Factors Related to Obstructive Sleep Apnea Diagnoses: A Brief Review

Sleep apnea is a clinical condition characterized by cessation of breathing in the sleeper due to pharyngeal airway closure. The reduction in air exchange results in decreased cerebral blood circulation with consequential behavioral deficits cognitively and emotionally. Untreated sleep apnea is associated with chronic illnesses of depression, cardiovascular disorder, obesity and diabetes mellitus. Measured cognitive behavior before and following CPAP treatment demonstrates the cognitive deficit as the effectiveness of CPAP treatment. Emotional factors related to sleep apnea diagnosis and adherence to treatment are facilitated in patients with cognitive behavior therapy (CBT) interventions by sleep specialists. This is a brief review paper that presents findings about cognition and emotional factors related to sleep apnea. This is a brief review paper.

Turbulent Kinetic Energy of Flow during Inhale and Exhale to Characterize the Severity of Obstructive Sleep Apnea Patient

This paper aims to investigate and present the numerical investigation of airflow characteristics using Turbulent Kinetic Energy(TKE)to characterize the upper airway with obstructive sleep apnea(OSA)under inhale and exhale breathing conditions.The importance of TKE under both breathing conditions is that it showan accuratemethod in expressing the severity of flow in sleep disorder.Computational fluid dynamics simulate the upper airway’s airflow via steady-state Reynolds-averaged Navier-Stokes(RANS)with k–ωshear stress transport(SST)turbulencemodel.The three-dimensional(3D)airway model is created based on the CT scan images of an actual patient,meshed with 1.29 million elements using Materialise Interactive Medical Image Control System(MIMICS)and ANSYS software,respectively.High TKE were noticed around the region after the necking(smaller cross-sectional area)during the inhale and exhale breathing.The turbulent kinetic energy could be used as a valuablemeasure to identify the severity of OSA.This study is expected to provide a better understanding and clear visualization of the airflow characteristics during the inhale and exhale breathing in the upper airway of patients for medical practitioners in the OSA research field.

Effects of obstructive sleep apnea on retinal microvasculature

AIM:To detect retinal microvascular variations in obstructive sleep apnea syndrome patients.METHODS:This prospective,observational case-control study included healthy controls and patients with mild,moderate,and severe obstructive sleep apnea syndrome.Vascular parameters,foveal avascular area,and flow areas in macula-centered,6.00×6.00 mm2 scan size optical coherence tomography angiography images were compared.RESULTS:The control group had the highest whole image,parafoveal,and perifoveal vessel density among the groups in both superficial and the deep capillary plexus(all P<0.05).Rapid eye movement sleep apnoea-hypopnoea index was reversely correlated with whole(Rho=-0.195,P=0.034),parafoveal(Rho=-0.242,P=0.008),perifoveal(Rho=-0.187,P=0.045)vessel density in the superficial capillary plexus,and whole(Rho=-0.186,P=0.046),parafoveal(Rho=-0.260,P=0.004),perifoveal(Rho=-0.189,P=0.043)vessel density in the deep capillary plexus,though the mean and non-rapid eye movement sleep apnoeahypopnoea index related with only parafoveal vessel density in the superficial capillary plexus(Rho=-0.213,P=0.020;Rho=-0.191,P=0.038)and the deep capillary plexus(Rho=-0.254,P=0.005;Rho=-0.194,P=0.035).CONCLUSION:This study shows decreased vessel density and its reverse correlation with the apnoea-hypopnoea index in patients with obstructive sleep apnea syndrome.

Forced Inspiratory Flow Volume Curve in Patients with Obstructive Sleep Apnea-Hypopnea Syndrome

Objective: Obstructive sleep apnea-hypopnea syndrome (OSA) is a disease of obstructive apnea or hypopnea caused by a repeated partial or complete collapse of the upper airway during sleep. The inspiratory part of the flow-volume curve (F-V curve) can be used as an auxiliary means to evaluate upper airway obstruction in adults. This study is to evaluate the ability of the F-V curve to predict the OSA and explore inspiratory indicators related to airway obstruction during sleep. Methods: There were 332 patients included in this cross-sectional study, who were accompanied by snoring, daytime sleepiness and other symptoms, with suspicion of OSA. According to the nocturnal polysomnography, the subjects were distributed into mild to moderate OSA group, severe OSA group and non-OSA group. A pulmonary function test was used to collect the subjects’ spirometry and F-V curves. Results: There was no significant difference in a variety of indices derived from the F-V curve between OSA and normal subjects, including 25% inspiratory flow rate, middle inspiratory flow rate, 75% inspiratory flow rate, peak flow rate, and forced inspiratory flow rate in the first second. The pulmonary function parameters were significantly correlated with the weight, age and sex of the subjects. Conclusion: These findings suggest that the inspiratory curve of pulmonary function cannot evaluate the upper airway abnormalities in patients with obstructive apnea-hypopnea syndrome.

Effects and Predictions of Oral Appliances in Obstructive Sleep Apnea

Since April 2004, the Asahi University Medical and Dental Center (hereinafter referred to as our center) has been providing oral appliances (hereinafter referred to as OA) to treat patients diagnosed with obstructive sleep apnea. The effects of using the OA and progress of 71 patients who received treatment at our center by wearing OA from March 2005 to the end of March 2016 were examined through questionnaires sent by physical mail. In 21 of 24 patients who underwent polysomnography after wearing OA, the apnea-hypopnea index (hereinafter referred to as AHI) significantly decreased after wearing OA (9.44 ± 10.37) compared to that before wearing OA (24.02 ± 13.57) (p = 8.7 × 10-8). The results showed that for patients who continuously use OA, it is necessary to have sound sleep/sleep soundly;further, the patients experienced a decrease in snoring when wearing OA, with only a few side effects on the temporomandibular joints and teeth. In addition, the closer the distance from the plane of the lower margin of the mandible to the hyoid bone after wearing OA, the more likely it was for the AHI to decrease, which suggests that wearing OA contributes to the prediction of therapeutic effects.

Epidemiological and Clinical Profile of Hypertensive Patients with Obstructive Sleep Apnea at CHU-B

Objectives: To detect obstructive sleep apnea syndrome (OSAS) in a population of hypertensive patients, using the Berlin questionnaire and to establish the epidemiological and clinical profile of patients. Patients and Method: This was a cross-sectional and analytical study, carried out from March to August 2019 at the CHU Brazzaville. Included are hypertensive patients followed as outpatients. The diagnosis of the OSAS was based on the answers to the Berlin questionnaire. Results: A total of 315 patients were included, including 210 women (64.9%). Prevalence of OSAS was 75.8% (n = 239). The average age of patients with sleep apnea was 58.5 ± 12.4 years with female predominance (64.9%). In the mixed analysis, the factors associated with (OSAS) were: occupation OR (2.56) 95% CI (1.15 - 5.69), obesity OR 7.50 (1.60 - 35.1) and abdominal obesity OR 2.36 CI 95% (1.36 - 4.08). Living standards were high in 59 cases (18.7 per cent). The medical history of previous hospitalization was present in 209 cases (66.3%), diabetes 95 (30.2%), and heart failure 57 cases (18.1%). Lifestyle patterns were: sedentary (n = 181;57.5%) alcohol consumption (n = 97;30.8%). On physical examination, overweight was noted in 96 cases (30.5%) and obesity in 91 cases (28.8%). The anomalies in the Berlin questionnaire were: snoring (n = 197;62.5%), waking fatigue (n = 127;40.3%), fatigue during the day (n = 97;30.8%). Conclusion: The prevalence of obstructive sleep apnea syndrome is high during arterial hypertension in our setting. Hence the need for sleep exploration through polysomnography, and prevention through the fight against the associated risk factors.

Holter ECG-Based Apnea Hypopnea Index to Screen Obstructive Sleep Apnea: A New Proposal and Evaluation of Feasibility

Obstructive sleep apnea syndrome (OSAS) is a common sleep disorder. It has been reported that approximately 40% of patients with moderate or severe OSAS die within the first eight years of disease. In hospitals, OSAS is inspected using polysomnography, which uses a number of sensors. Because of the cumbersome nature of this polysomnography, an initial OSAS screening is usually conducted. In recent years, OSAS screening techniques using Holter electrocardiogram (ECG) have been reported. However, the techniques so far reported cannot perform an OSAS severity assessment. The present study presents a new method to distinguish the obstructive sleep apnea (OSA) and non-OSA epochs at one-second intervals based on the Apnea Hypopnea Index assessment, defined as the duration of continuous apnea. In the proposed method, the time-frequency components of the heart rate variability and three ECG-derived respiration signals calculated by the complex Morlet wavelet transformation are adopted as features. A support vector machine is employed for classification. The proposed method is evaluated using three eight-hour ECG recordings containing OSA episodes from three subjects. As a result, the sensitivity and specificity of classification are found to reach approximately 90%, a level suitable for OSAS screening in clinical settings.

Does Obstructive Sleep Apnea (OSA) Increase the Risk of Post-Operative Respiratory Complications after Bariatric Surgery?

Background: OSA affects up to quarter of general population. It is associated with morbid obesity with a higher morbidity and mortality rates. STOP Bang questionnaire is a validated method for OSA screening. OSA patients are at high risk of developing airway obstruction, cardiac events, congestive heart failure, stroke and desaturation post operatively. The aim of this study is to evaluate adverse respiratory events in patients undergoing bariatric surgery in relation to risk of OSA using Stop Bang questionnaire. Methods: This prospective double cohort study was conducted in Tanta University Hospital from Marchto August 2017. During the preoperative assessment, STOP-BANG questionnaire was performed. After extubation, patients were transferred to PACU unit. Respiratory complications were assessed thereafter. Based on STOP-BANG score, patients were divided into two groups, high risk of OSA with STOP-BANG > 3 (Group I) and low risk of OSA with STOP-BANG Results: 104 patients were included in this study. Group I had more comorbidities in the form of CAD (15% versus 2%, P 0.001). Higher number of respiratory complications was noted in high-risk group (31 patients, 59%) compared to (24 patients, 46%) in group II yet, it was not significant. Conclusion: Obese patients with STOP-BANG score > 3 undergoing bariatric surgery are associated with hypertension, dyslipidemia, CAD, and renal insufficiency. High-risk OSA obese patients are at higher risk of developing respiratory compilations like inability to breathe deeply and hypoxia in postoperatively.

Processing obstructive sleep apnea syndrome (OSAS) data

In this study, the EEG signals were processed. Thirteen ICA algorithms were tested to verify the performance efficiency. The EEG signals were recorder using 10/20 international system, based on a 20 minute sleep recording of a severe Obstructive Sleep Apnea Syndrome (OSAS) during NREM and REM sleep. Seven channels were used to record the EEG signals which are sampled at 100 Hz. The performance analysis of the algorithms were investigated to eliminate the loss of the informative EEG signal during the data processing. The denoising results were magnified with the purpose of evaluating the robustness of the denoising algorithms. From the result we obtained, we are able to understand the denoising algorithm is more suitable to process the EEG signal with lower amplitude.

Therapeutic Path of Dental Expertise in Obstructive Sleep Apnea Syndrome (OSAS)

Obstructive Sleep Apnea Syndrome (OSAS) is a respiratory sleep disorder characterized by repeated episodes of complete or partial obstruction of the upper airway. OSAS has a frequency of 4 percent and is classified according to the number of obstructive sleep apnea-hypopnea episodes. The OSAS diagnostic path starts with the evaluation of the patient’s clinical framework and follows an instrumental procedure, depending on the clinical severity of the patient. Dental practitioners have the ability to intercept early on the signs and symptoms of OSAS. At the same time, they can assess whether the patient has the indications for treatment with specific oral devices (Oral Appliances, OA). The purpose of this paper is to provide guidance for dental management of obstructive sleep apnea syndrome in adult individuals.

低温等离子消融技术与电刀凝切技术在OSAHS中的应用效果对比

目的 分析比较低温等离子消融技术与电刀凝切技术在阻塞性睡眠呼吸暂停低通气综合征(OSAHS)中的应用效果。方法 回顾性分析我院92例行手术治疗的OSAHS患者临床资料,其中48例行低温等离子消融术联合悬雍垂腭咽成形术(UPPP)治疗(观察组),44例行电刀凝切UPPP治疗(对照组)。记录两组围术期指标、术后疼痛程度[视觉模拟评分法(VAS)]、术后并发症及临床疗效,比较两组术前、术后6个月多导睡眠图(PSG)参数[睡眠呼吸暂停低通气指数(AHI)、最低血氧饱和度(LSaO_(2))]变化情况。结果 两组术后创面假膜开始脱落时间及假膜彻底脱落时间、术后并发症发生率比较,差异无统计学意义(P>0.05);观察组手术时间、术中出血量均低于对照组(P<0.05)。两组术后VAS评分均逐渐降低(P<0.05),观察组术后VAS评分均低于对照组(P<0.05)。观察组、对照组分别有42、39例患者具有术后12个月的检查数据,分别有16例、11例患者具有术后24个月的检查数据;观察组术后6个月、术后12个月、术后24个月临床疗效均显著高于对照组(P<0.05)。术后6个月时,两组AHI均较术前降低(P<0.05),且观察组术后低于对照组(P<0.05);LSaO_(2)较术前升高(P<0.05),且观察组术后高于对照组(P<0.05)。结论 低温等离子消融技术术中可联合舌根部消融治疗,对中重度OSAHS近远期疗效均较好,术区损伤小,临床应用价值高。

基于多中心的老年OSAHS合并冠心病患者不良预后的Nomogram预测模型构建

目的基于多中心分析老年阻塞性睡眠呼吸暂停低通气综合征(OSAHS)合并冠心病患者不良预后的影响因素并构建Nomogram预测模型。方法于2020年3月至2022年3月选取江苏省中医院共357例老年OSAHS合并冠心病患者,按照7∶3比例将纳入患者分为建模组(n=250)及验证组(n=107)。对患者进行为期1年的随访,根据患者预后将建模组分为预后良好组(n=215)和预后不良组(n=35)。单因素及多因素Logistic回归分析影响老年OSAHS合并冠心病患者不良预后的因素,并根据此结果构建Nomogram预测模型,再以H-L拟合度曲线评估模型的有效性,以受试者工作特征(ROC)曲线评估模型的区分度。结果单因素分析结果显示,体重指数、睡眠呼吸暂停低通气指数(AHI)、睡眠平均氧饱和度(SaO_(2))、超敏C反应蛋白(hs-CRP)及白细胞介素-6(IL-6)为老年OSAHS合并冠心病患者不良预后的影响因素(P<0.05)。多因素Logistic回归分析显示,体重指数较高、AHI水平较高、hs-CRP水平较高、低水平的睡眠平均SaO_(2)为老年OSAHS合并冠心病患者不良预后的影响因素(P<0.05)。验证模型显示,建模组χ^(2)=6.125,P=0.421,ROC曲线下面积AUC为0.958(95%CI:0.926~0.980),敏感度及特异度分别为82.86%、96.28%;验证组χ^(2)=5.754,P=0.311,AUC为0.932(95%CI:0.893~0.960),敏感度及特异度分别为85.70%、88.40%。结论体重指数较高、AHI水平较高、hs-CRP水平较高、低水平的睡眠平均SaO_(2)为老年OSAHS合并冠心病患者不良预后的影响因素,以此构建的Nomogram预测模型具有较好的区分度及有效性,可帮助临床预测患者不良预后的发生风险,具有较高的临床价值。

OSA可能是引发麻醉意外的一种尚未被认识的原因

临床上对于麻醉意外的认识以往并未包括睡眠呼吸暂停问题。特别是全麻患者发生术中和术后合并症时,一般认为所涉及的原因大多是麻醉期间发生的反流、误吸、缺氧、吸氧、呼吸抑制、急性呼吸衰竭、术后苏醒延迟,很少涉及阻塞性睡眠呼吸暂停(OSA)问题。近年来,随着人们对于睡眠呼吸暂停危害认识的逐渐深入和扩展,发现外科麻醉时产生的问题可能与OSA有关。本研究在长期临床实践经验的基础上,推测OSA可能是造成麻醉意外(主要是全麻)的一种尚未被认识和重视的原因。本研究按照顺序逐层剖析和阐述其推测过程,在梳理导致OSA高危因素和发病条件的基础上,重点阐述OSA与麻醉意外之间的关系,分析OSA引发麻醉意外的原因,强调应充分认识OSA引发麻醉意外的危害,指出OSA患者术前若未进行必要的筛查诊断和干预处理,可能会出现系列不良后果;麻醉医生应时刻加强OSA患者围手术期的管理。

腺样体联合扁桃体切除术对OSAHS患儿睡眠质量的影响

目的:探讨腺样体联合扁桃体切除术对阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患儿睡眠质量的影响。方法:选取郑州儿童医院2021年1月至2022年7月收治的98例OSAHS患儿,随机分为对照组和观察组,各49例。对照组采用单纯腺样体切除术,观察组采用腺样体联合扁桃体切除术。比较两组患儿治疗后临床疗效、手术前后呼吸暂停通气指数(AHI)、阻塞性呼吸暂停指数(OAI)、最低血氧饱和度(LSaO_(2))水平变化、睡眠质量及OSAHS对生活质量的影响程度,并统计6个月内并发症情况。结果:治疗后观察组患儿临床总有效率高于对照组,差异具有统计学意义(P<0.05)。与术前比较,出院时两组患儿AHI及OAI水平均降低,且观察组患儿AHI及OAI水平均低于对照组,差异具有统计学意义(P<0.05);出院时两组患儿LSaO_(2)水平均明显高于术前,差异具有统计学意义(P<0.05),但组间LSaO_(2)水平比较,差异无统计学意义(P>0.05)。与术前比较,出院时两组患儿匹茨堡睡眠质量指数量表(PSQI)评分、Epworth嗜睡量表(ESS)评分及儿童OSAHS疾病特异性生活质量调查量表(OSA-18)评分均降低,且观察组患儿PSQI、ESS及OSA-18评分均低于对照组,差异具有统计学意义(P<0.05)。术后6个月内,观察组患儿并发症发生率低于对照组,差异具有统计学意义(P<0.05)。结论:腺样体联合扁桃体切除术可更有效地降低OSAHS患儿AHI、OAI水平,改善其睡眠、生活质量,降低术后扁桃体再度增生及扁桃体反复发炎风险,整体临床疗效优于单纯腺样体切除术,对于腺样体和扁桃体肥大的患儿,建议同时切除腺样体和扁桃体。

Effect of obstructive sleep apnea on type 2 diabetes mellitus:A comprehensive literature review

Obstructive sleep apnea(OSA)is frequently associated with obesity and metabolic syndrome.Also frequently associated with metabolic syndrome is type 2 diabetes mellitus(T2DM).Therefore,it is common to find OSA and T2DM together in individuals with metabolic syndrome.Additionally,both OSA and T2DM have a common pathophysiological link with development of insulin resistance.Individuals with severe insulin resistance are likely to have inadequate glycemic control.Long standing poorly controlled T2DM is associated with debilitating microvascular complications such as retinopathy,nephropathy,neuropathy and macrovascular complications such as coronary artery and cerebrovascular disease.There is extensively published literature exploring the cause-effect relationship between OSA and T2DM.In this article we provide an in-depth review of the complex pathophysiological mechanisms linking OSA to T2DM.Specifically,this review focusses on the effect of OSA on the microvascular complications of T2DM such as retinopathy,nephropathy and neuropathy.Additionally,we review the current literature on the effect of continuous positive airway pressure use in individuals with T2DM and OSA.

Relationship between brain—derived neurotrophic factor and cognitive function of obstructive sleep apnea/hypopnea syndrome patients

Objective:To determine the relationship between the blood serum brain-derived neurotrophic factor（BDNF） level and cognitive function deterioration in patients with obstructive sleep apnea/ hypopnea syndrome（OSAHS）,and to explore the possible mechanism of cognitive impairment. Methods:Twenty-eight male OSAHS patients and 14 normal males（as controls） were enrolled in the study.Polysomnography and the Montreal cognitive assessment（MoCA） were conducted. The blood serum BDNF levels were measured using ELISA.Results:The OSAHS group had significantly decreased blood serum BDNF levels compared with the control group（t=-10.912, P=0.000）.The blood serum BDNF level of the subjects was significantly positively associated with the MoCA score（r=0.544,P=0.000）,significantly negatively associated with the apneahypopnea index（AHI） and shallow sleep（S1+S2）（AHI:r=-0.607,P=0.000;S1+S2:r =-0.768,P= 0.000）,and significantly positively associated with the lowest SaO2（LSO）,slow wave sleep（S3+S4）, and rapid eye movement sleep（REM）（LSO:r=0.566,P = 0.000;S3+S4:r=0.778,P=0.000;REM: r=0.575,P=0.000）.Conclusions:OSAHS patients have significantly decreased blood serum BDNF levels compared with the control.Nocturnal hypoxia as well as the deprivation of slow wave sleep and REM may lead to the decreased serum BDNF level of OSAHS patients.This decreased blood serum BDNF level may contribute to the cognitive impairment in OSAHS.

Atrial fibrillation in obstructive sleep apnea

Atrial fibrillation(AF) is a common arrhythmia with rising incidence.Obstructive sleep apnea(OSA) is prevalent among patients with AF.This observation has prompted significant research in understanding the relationship between OSA and AF.Multiple studies support a role of OSA in the initiation and progression of AF.This association has been independent of obesity,body mass index and hypertension.Instability of autonomic tone and wide swings in intrathoracic pressure are seen in OSA.These have been mechanistically linked to initiation of AF in OSA patients by lowering atrial effective refractory period,promoting pulmonary vein discharges and atrial dilation.OSA not only promotes initiation of AF but also makes management of AF difficult.Drug therapy and electrical cardioversion for AF are less successful in presence of OSA.There has been higher rate of early and overall recurrence after catheter ablation of AF in patients with OSA.Treatment of OSA with continuous positive airway pressure has been shown to improve control of AF.However,additional studies are needed to establish a stronger relationship between OSA treatment and success ofAF therapies.There should be heightened suspicion of OSA in patients with AF.There is a need for guidelines to screen for OSA as a part of AF management.

Association between Serum Homocysteine and Oxidative Stress in Elderly Patients with Obstructive Sleep Apnea/hypopnea Syndrome

Objective Elderly patients with obstructive sleep apnea/hypopnea syndrome （OSAHS） has a higher risk of cardiovascular and cerebrovascular disease. However, changes of homocysteine （Hey） as markers of cardiovascular and eerebrovascular disease associated with OSAHS and their mechanism have not been elucidated so far. This study aims to investigate the changes of both serum Hcy and oxidative stress and their possible links with OSAHS in elderly patients. Methods Based on polysomnogram （PSG） and age, 83 patients with OSAHS were recruited and divided into elderly-OSAHS （n=32） and non-elderly OSAHS groups （n=51）. Fifty two subjects without OSAHS were divided into elderly control （n=29） and non-elderly control groups （n-23）. A total of 135 subjects were included in the present study. All subjects were recorded for PSG variables and the contents of homocysteine （Hcy）, malonaldehyde （MDA）, and glutathione （GSH） which were detected after sleep. Serum homocysteine was measured by cyclophorase. MDA and GSH were measured by speetrophotometer. Results （1） The serum levels of Hcy showed significant difference among the four groups （P〈0.05）. The concentrations of Hcy in elderly OSAHS patients were higher than in other groups, while those in the elderly control group were higher than in the non-elderly control; the concentrations in the non-elderly OSAHS group were higher than in the non-elderly control. （2） The concentrations of MDA and GSH changed at an equal pace with Hcy in the four groups. （3） Multielement linearity regression analysis indicated a statistically significant relationship between Hcy concentration and age, MDA, GSH, and apnea hypopnea index （AHI）. Conclusions （1） The concentrations of Hcy and oxidative stress have increased with advancing age. （2） The concentrations of Hcy and oxidative stress have further increased in the elderly patients with OSAHS. （3） Oxidative stress might cause high-level serum Hcy in the elderly patients with OSAHS.

Secreted Frizzled-Related Protein 5 (SFRP5) in Patients with Obstructive Sleep Apnea

Objective Obstructive sleep apnea (OSA) is closely related to obesity, insulin resistance and inflammation. Secreted frizzled-related protein 5 (SFRP5) is a recently discovered adipokine. It is involved in insulin resistance and inflammation in obesity. This study aimed at evaluating the association between SFRP5and sleeping characteristics as well as biochemical parameters of OSA patients.Methods This was a prospective case control study. Nondiabetic OSA patients and controls were consecutively recruited and divided into three groups: OSA group, apnea–hypopnea Index (AHI)≥5/h; healthy controls with normal body mass index (BMI); obese controls without OSA, and BMI > 24.0 kg/m2. All participants underwent polysomnography (PSG). Plasma SFRP5 was examined using enzyme-linked immunosorbent assay (ELISA). Blood biochemical examinations, including fasting blood glucose (FBG), lipid profile, hypersensitive Creactive protein (hsCRP), were performed early in the morning after PSG. Patients with severe OSA were treated with nasal continuous positive airway pressure (nCPAP), and plasma SFRP5 was repeatedly measured for comparison.Results Sixty-eight subjects were enrolled in the study, including 38 patients of OSA, whose medium AHI was 58.70 /h (36.63, 71.15), 20 obese controls, and 10 healthy controls. The plasma SFRP5 level of OSA patients was not significantly different from that of healthy controls or obese controls. In OSA patients, SFRP5 level correlated positively with triglyceride level (r=0.447, P=0.005) and negatively with LDL-cholesterol level and HDLcholesterol level (r=?0.472 and P=0.003; r=?0.478 and P=0.002; respectively). SFRP5 level was not found correlating with FBG, AHI, or any of nocturnal hypoxia parameters. After overnight nCPAP treatment, plasma SFRP5 levels of OSA patients did not change significantly (t=1.557, P = 0.148) compared to that of pretreatment.Conclusions In nondiabetic OSA patients, plasma SFRP5 is associated with the lipid profile. However,no correlation was observed between SFRP5 and FBG or sleep parameters. The SFRP5 level of OSA patients did not differ from that of non-OSA individuals in our study.