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.

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.

Electrical Stimulation Therapy Improves Sleep Respiratory Parameters in Obstructive Sleep Apnea Syndrome: A Meta-analysis

Recent clinical trials have shown that electrical stimulation has beneficial effects in obstruc- tive sleep apnea syndrome （OSAS）. The purpose of this study was to evaluate the efficacy of electrical stimulation therapy for OSAS with a meta-analysis. The meta-analysis of all relative studies was per- formed through searching international literature, including PUBMED, CNKI, and EMBASE databases. This literature analysis compared all patients undergoing electrical stimulation therapy with respect to the respiratory disturbance index （RDI） and changes in sleep structure. Six studies were selected in- volving a total of 91 patients. The meta-analysis indicated that electrical stimulation therapy reduced RDI, longest apnea time, and improved the minimum SaO2. Based on the evidence found, electrical stimulation may be a potential therapy for OSAS, warranting further clinical trials.

Impact of continuous positive airway pressure therapy for nonalcoholic fatty liver disease in patients with obstructive sleep apnea

BACKGROUND Obstructive sleep apnea(OSA)has been suggested as an independent risk factor for nonalcoholic fatty liver disease(NAFLD),and continuous positive airway pressure(CPAP)is the first-line therapy for OSA.AIM To clarify the efficacy of effective CPAP therapy on NAFLD of OSA patients by serum markers and transient elastography(TE)using FibroScan®(Echosens,Paris,France).METHODS We prospectively enrolled 123 consecutive patients with OSA who met the indications for CPAP.Liver fibrosis and steatosis were assessed using TE.Before and after 6 mo of CPAP therapy,serum markers and TE were assessed for all patients.The mean usage rate of CPAP therapy for 6 mo was arbitrarily calculated in each patient and expressed as“mean compliance index”(m-CI).RESULTS In 50 OSA patients with NAFLD,both aspartate aminotransferase(AST)and alanine aminotransferase(ALT)levels were significantly decreased after 6 mo of CPAP therapy.Univariate analysis showed that decreased body weight(BW),decreased body mass index(BMI),decreased AST level,decreased hemoglobin A1c,and high m-CI were significantly related with improved ALT level.In multivariate regression model adjusted for quantities of BW change during 6 mo of CPAP therapy,high m-CI tended to improve ALT level(P=0.051).All 17 OSA patients with NAFLD,high m-CI and no BMI changes showed significant improvements in AST and ALT levels.Meanwhile,no significant changes in TE data or serum fibrosis markers were seen.CONCLUSION Some NAFLD could be associated with chronic intermittent hypoxia due to OSA independent of BW changes.In those cases,adequate reoxygenation from effective CPAP therapy may improve NAFLD.

Association between non-alcoholic fatty liver disease and obstructive sleep apnea

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is an emerging liver disease and currently the most common cause of incidental abnormal liver tests.The pathogenesis of NAFLD is multifactorial and many mechanisms that cause fatty liver infiltration,inflammation,oxidative stress and progressive fibrosis have been proposed.Obstructive sleep apnea(OSA)may be linked with the pathogenesis and the severity of NAFLD.AIM To study the association between NAFLD and OSA considering also the efficacy of continuous positive airway pressure(CPAP)treatment.METHODS A Pub Med search was conducted using the terms"non-alcoholic fatty liver disease AND(obstructive sleep apnea OR obstructive sleep disorders OR sleep apnea)".Research was limited to title/abstract of articles published in English in the last 5 years;animal and child studies,case reports,commentaries,letters,editorials and meeting abstracts were not considered.Data were extracted on a standardized data collection table which included:First author,publication year,country,study design,number of patients involved,diagnosis and severity of OSA,diagnosis of NAFLD,patient characteristics,results of the study.RESULTSIn total,132 articles were initially retrieved on Pub Med search and 77 in the last five years.After removal of irrelevant studies,13 articles were included in the qualitative analysis.There was a total of 2753 participants across all the studies with a mean age between 42 and 58 years.The proportion of males ranged from21%to 87.9%and the mean body mass index ranged from 24.0 to 49.9 kg/m2.The results of this review showed an increased prevalence of NAFLD in patients with diagnosis of OSA,even in the absence of coexisting comorbidities such as obesity or metabolic syndrome.Furthermore,the severity of NAFLD is associated with the increase in OSA severity.Effective CPAP treatment,although not always decisive,may stabilize or slow NAFLD progression with benefits on metabolic and cardiovascular functions.CONCLUSION In NAFLD patients,although asymptomatic,it is recommended to systematically perform polysomnography in order to early and better treat them before the development of potentially life threatening systemic dysfunctions.

Intermittent hypoxia is involved in gut microbial dysbiosis in type 2 diabetes mellitus and obstructive sleep apnea-hypopnea syndrome

BACKGROUND Obstructive sleep apnea(OSA)-hypopnea syndrome(OSAHS)has been recognized as a comorbidity of type 2 diabetes mellitus(T2DM);more than half of T2DM patients suffer from OSAHS.Intermittent hypoxia(IH)plays an important role in metabolic diseases,such as obesity and OSAHS,through various mechanisms,including altering the gut microecological composition and function.Therefore,it is important to study the role of gut microbiota in T2DM patients with OSAHS,which has a high incidence and is prone to several complications.AIM To assess whether IH is involved in altering the fecal microbiome in T2DM patients with OSAHS.METHODS Seventy-eight participants were enrolled from Henan Province People’s Hospital and divided into healthy control(HC,n=26),T2DM(n=25),and T2DM+OSA(n=27)groups based on their conditions.The fecal bacterial DNA of the research participants was extracted and subjected to 16S ribosomal RNA sequencing.The clinical indices,such as insulin resistance index,homocysteine(HCY)concentration,and the concentrations of inflammatory factors in the peripheral blood,were assessed and recorded.RESULTS Group T2DM+OSA had the highest apnea-hypopnea index(AHI)(2.3 vs 3.7 vs 13.7),oxygen desaturation index(0.65 vs 2.2 vs 9.1),HCY concentration(9.6μmol/L vs 10.3μmol/L vs 13.81μmol/L)and C-reactive protein(CRP)concentrations(0.3 mg/L vs 1.43 mg/L vs 2.11 mg/L),and lowest mean oxygen saturation(97.05%vs 96.6%vs 94.7%)among the three groups.Twelve and fifteen key differences in amplicon sequence variants were identified when comparing group T2DM+OSA with groups T2DM and HC,respectively.We found progressively decreased levels of Faecalibacterium,Eubacterium,and Lachnospiraceae,and an increase in the level of Actinomyces,which strongly correlated with the HCY,CRP,fasting plasma glucose,and hemoglobin A1c concentrations,AHI,mean oxygen saturation,and insulin resistance index in group T2DM+OSA(P<0.05).CONCLUSION For T2DM patients with OSAHS,IH may be involved in selective alterations of the gut microbiota,which may affect the pathophysiological development of T2DM and DM-related complications.

Neuropsychological Functioning after Adenotonsillectomy in Children with Obstructive Sleep Apnea:A Meta-analysis

The present study aimed to investigate the efficacy of adenotonsillectomy(AT) for children with obstructive sleep apnea syndrome(OSAS) and the improvement of their cognitive function. Studies on cognitive performance of OSAS children treated with or without AT were identified by searching the Pubmed, EMBASE and Cochrane library. A meta-analysis was conducted to analyze the literature. The random-effects model was used to evaluate 11 eligible studies using an inverse-variance method. The neuropsychological test results of 4 cognitive domains(general intelligence, memory, attention-executive function and verbal ability) were obtained and analyzed. By comparison of cognitive function between OSAS children and healthy controls, the effect sizes of each domain were achieved as follows: general intelligence, –0.5(P<0.0001); memory, –0.18(P=0.02); attention-executive function, –0.21(P=0.002); and verbal ability, –0.48(P=0.0006). The effect sizes of general intelligence, memory, attention-executive function, and verbal ability after AT compared to baseline level were –0.37(P=0.008), –0.36(P=0.0005), –0.02(P=0.88), and –0.45(P=0.009), respectively. Comparing the cognitive ability between OSAS children after AT and healthy controls showed that the effect sizes were –0.54(P=0.0009), –0.24(P=0.12), –0.17(P=0.35), and –0.45(P=0.009) in general intelligence, memory, attention-executive function, and verbal ability, respectively. Our results confirmed that OSAS children performed worse than healthy children in terms of the 4 cognitive domains investigated. After 6–12 months of observation, significant improvement in attention-executive function and verbal ability were found in OSAS children treated with AT compared to their baseline level; restoration of attention-executive function and memory were observed in OSAS children after AT in comparison to healthy controls. Further rigorous randomized controlled trials should be conducted to obtain definitive conclusions.

Prospective study of the prevalence and co-morbidities of obstructive sleep apnea in active-duty army personnel in the three southernmost provinces of Thailand using questionnaire screening

Background: It is crucial for the army to know the prevalence of obstructive sleep apnea(OSA) syndrome in activeduty army personnel. Little information has been reported on the prevalence of OSA and clinical features in activeduty army personnel. This study was aimed to estimate the prevalence of snoring and risk of developing OSA in activeduty army personnel in Thailand and to identify the co-morbidities of OSA. In total, 1107 participants who were aged20–60 years and were deployed to the three southernmost provinces of Thailand were enrolled. All the participants completed the Phramongkutklao(PMK) Hospital OSA Questionnaire that was modified and validated from the Berlin Questionnaire and underwent physical examination. The participants were 1107 active-duty army personnel in the three southernmost provinces of Thailand, both males and females, aged 20–60 years.Methods: The PMK OSA Questionnaire was used to assess the risk of OSA together with interviewing for snoring,fatigue, falling asleep and day-time sleepiness. Physical examination of the neck, chest and hip circumference,and height was performed. Information concerning physical training, co-morbid diseases, smoking and alcoholic consumption was collected.Results: The prevalence of snoring was 58.5, and 4.8% met the PMK OSA Questionnaire criteria, thus indicating a high risk of OSA. The information obtained indicated that laryngopharyngeal reflux(LPR), current smoking and alcoholic consumption were significantly higher in the high-risk OSA group.Conclusions: Early detection and treatment of OSA in active-duty army personnel are imperative. Physical examination and polysomnography can be used to reveal the high-risk group. High body mess index(BMI), laryngopharyngeal reflux, current smoking and alcoholic consumption are modifiable factors for OSA and are avoidable. A policy to decrease the BMI and risk of LPR, as well as to stop smoking and alcoholic consumption, should be applied.

Prognostic predictors on the efficacy of oral appliance therapy for obstructive sleep apnea syndrome

Objectives: The aim of this study was to identify independent prognostic predictors of the efficacy of oral appliance (OA) therapy for obstructive sleep apnea syndrome (OSAS). Materials and methods: The subjects consisted of 89 patients (77 males and 12 females) in whom OSAS had been treated with an OA. The mean age of the subjects was 52.4 years (range: 20 to 78 years) and mean body mass index (BMI) was 23.9 kg/m2 (range: 17.3 to 32.2 kg/m2). Lateral cephalograms were taken and 15 angle, 15 distance and 5 area measurements were calculated by means of a computerized program. Overnight polysomnography (PSG) was performed before treatment and several months after titration of OA therapy. OA therapy was considered effective if the apnea-hypopnea index several months after titration was under 15 events/h and was reduced to at least 50% of that before treatment. The examined data such as patient age, sex, BMI, data from cephalometric analyses, Epworth sleepiness scale, and data for pretreatment PSG were analyzed statistically, and multivariate logistic regression analysis was performed to clarify predictive variables for treatment outcome. Results: LFH (OR = 0.350;p = 0.035) and McN-A (OR = 0.276;p = 0.057) were selected as independent predictors from the explanatory variables. The predictive accuracy of the calculated logistic regression model was 74.2%. Conclusion: This results show that OA therapy for OSAS is more effective in patients with large anteroposterior diameter of the maxilla and large lower facial height.

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.

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.

The Change of Interleukin-6 and Tumor Necrosis Factor in Patients with Obstructive Sleep Apnea Syndrome

The levels of lipopolysaccharide (LPS) induced interleukin 6 (IL 6) and tumor necrosis factor α (TNF α) expression in culture of peripheral blood mononuclear cells (PBMC) and the plasma levels of IL 6 and TNF α in the patients with obstructive sleep apnea syndrome (OSAS) were measured and the relationship between OSAS and IL 6 or TNF α expression studied. Both IL 6 and TNF α were detected by using ELISA in 22 patients with OSAS and 16 normal controls. The levels of LPS induced IL 6 (787.82±151.97 pg/ml) and TNF α (4165.45±1501.43 pg/ml) expression in the supernatant of the culture of PBMC and plasma level of IL 6 (50.67±4.70 pg/ml) and TNF α (299.09±43.57 pg/ml) in the patients with OSAS were significantly higher than those in the normal controls (in the supernatant of the culture of PBMC: 562.69±197.54 pg/ml and 1596.25±403.08 pg/ml respectively; in the plasma: 12.69±2.75 pg/ml and 101.88±21.27 pg/ml respectively). There were significantly positive correlation between the levels of IL 6 and TNF α and the percentage of time of apnea and hyponea, as well as the percentage of time spending at SaO 2 below 90 % in the total sleep time. It was concluded that LPS induced IL 6 and TNF α levels as well as plasma IL 6 and TNF α levels in the patients with OSAS were up regulated, which may be associated with the pathogenesis of OSAS.

Evaluation of Airway Obstruction at Soft Palate Level in Male Patients with Obstructive Sleep Apnea/Hypopnea Syndrome:Dynamic 3-Dimensional CT Imaging of Upper Airway

This study examined the dynamic characteristics of upper airway collapse at soft palate level in patients with obstructive sleep apnea/hypopnea syndrome（OSAHS） by using dynamic 3-Dimensional（3-D） CT imaging.A total of 41 male patients who presented with 2 of the following symptoms,i.e.,daytime sleepiness and fatigue,frequent snoring,and apnea with witness,were diagnosed as having OSAHS.They underwent full-night polysomnography and then dynamic 3-D CT imaging of the upper airway during quiet breathing and in Muller＇s maneuver.The soft palate length（SPL）,the minimal cross-sectional area of the retropalatal region（mXSA-RP）,and the vertical distance from the hard palate to the upper posterior part of the hyoid（hhL） were compared between the two breathing states.These parameters,together with hard palate length（HPL）,were also compared between mild/moderate and severe OSAHS groups.Association of these parameters with the severity of OSAHS [as reflected by apnea hypopnea index（AHI） and the lowest saturation of blood oxygen（LSaO2）] was examined.The results showed that 31 patients had severe OSAHS,and 10 mild/moderate OSAHS.All the patients had airway obstruction at soft palate level.mXSA-RP was significantly decreased and SPL remarkably increased during Muller＇s maneuver as compared with the quiet breathing state.There were no significant differences in these airway parameters（except the position of the hyoid bone） between severe and mild/moderate OSAHS groups.And no significant correlation between these airway parameters and the severity of OSAHS was found.The position of hyoid was lower in the severe OSAHS group than in the mild/moderate OSAHS group.The patients in group with body mass index（BMI）≥26 had higher collapse ratio of mXSA-RP,greater neck circumference and smaller mXSA-RP in the Muller＇s maneuver than those in group with BMI26（P0.05 for all）.It was concluded that dynamic 3-D CT imaging could dynamically show the upper airway changes at soft palate level in OSAHS patients.All the OSAHS patients had airway obstruction of various degrees at soft palate level.But no correlation was observed between the airway change at soft palate level and the severity of OSAHS.The patients in group with BMI≥26 were more likely to develop airway obstruction at soft palate level than those with BMI26.

Detection of cognitive impairment in patients with obstructive sleep apnea hypopnea syndrome using mismatch negativity

In this experiment, 97 patients with obstructive sleep apnea hypopnea syndrome were divided into three groups （mild, moderate, severe） according to minimum oxygen saturation, and 35 healthy subjects were examined as controls. Cognitive function was determined using the mismatch negativity paradigm and the Montreal Cognitive Assessment. The results revealed that as the disease worsened, the mismatch negativity latency was gradually extended, and the amplitude gradually declined in patients with obstructive sleep apnea hypopnea syndrome. Importantly, mismatch negativity latency in severe patients with a persistent time of minimum oxygen saturation 〈 60 seconds was significantly shorter than that with a persistent time of minimum oxygen saturation 〉 60 seconds. Correlation analysis revealed a negative correlation between minimum oxygen saturation latency and Montreal Cognitive Assessment scores. These findings indicate that intermittent night-time hypoxemia affects mismatch negativity waveforms and Montrea Cognitive Assessment scores. As indicators for detecting the cognitive functional status of obstructive sleep apnea hypopnea syndrome patients, the sensitivity of mismatch negativity is 82.93%, the specificity is 73.33%, the accuracy rate is 81.52%, the positive predictive value is 85.00%, the negative predictive value is 70.21%, the positive likelihood ratio is 3, and the negative likelihood ratio is 0.23. These results indicate that mismatch negativity can be used as an effective tool for diagnosis of cognitive dysfunction in obstructive sleep apnea hypopnea syndrome patients.

Effects of China-Germany Follow Up Systems on Ventilator Therapy in Patients with Obstructive Sleep Apnea Syndrome

Objective:To investigate the effects of different follow-up systems in China and Germany on ventilator therapy in patients with obstructive sleep apnea syndrome.Method:From March 2013 to October 2015,three hundred patients with moderate to severe obstructive sleep apnea syndrome and those who are suitable for ventilator treatment were followed up according to the follow-up system of both China and Germany.The follow-up was carried out for one year to compare the rate of loss to follow-up,ventilator therapy compliance,treatment effect,ventilator side effects and others in the two groups of patients.Statistical analysis was performed using x2 test,P<0.05 for the difference was statistically significant.Results:The rate of loss to follow-up in the German group was lower than that in the Chinese group.The compliance of the German group with respiratory therapy was lower than that of the Chinese group.The side effects of ventilator treatment were lower than those in the Chinese group(P<0.05).Conclusion:The German follow-up system is more effective than the Chinese follow-up system in improving the compliance and effectiveness of ventilator therapy in patients with obstructive sleep apnea syndrome.

Retinal nerve fiber layer thickness changes in obstructive sleep apnea syndrome: one year follow-up results

·AIM: To investigate the retinal nerve fiber layer(RNFL)thickness changes in patients with obstructive sleep apnea syndrome(OSAS) for one year follow-up. To discuss the possibility of detecting tendency of glaucoma in this population by using spectral domain optical coherence tomography(3D-OCT-2000 Spectral domain).·METHODS: After polysomnographic study, all subjects(64 OSAS patients and 40 controls) underwent detailed ophthalmological examination. After these examinations,patients with glaucoma and patients who had ophthalmological and/or systemic disease were excluded from the study.Totally, 20 patients in OSAS group and five patients in controls were excluded from the study in the first examination and follow-up period. The RNFL thickness was assessed with OCT. Forty-four OSAS patients and 35 control subjects were followed up for12 mo. RNFL thickness change and OSAS patients were evaluated for severity of disease by Apnea-Hypopnea Index(AHI).·RESULTS: Forty-four OSAS patients and 35 controls were enrolled in the study. Statistically significance was found between OSAS patients and controls at the 12 thmo.Average RNFL thickness was found to be significantly lower in last measurements in OSAS patients when compared with first measurements and control subjects(P 【0.001, 0.002, respectively). There was a statistically significant correlation among AHI, and RNFL thickness(P 【0.05).·CONCLUSION: The results suggest that the patients with OSAS were related with a proportional decrease in the RNFL thickness. These patients should be followed up regularly for glaucomatous changes. Detecting more RNFL thinning in severe OSAS was important.