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.

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.

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.

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.

Obstructive sleep apnea syndrome and fatty liver: Association or causal link?

Obstructive sleep apnea (OSA) is a complex disorder that consists of upper airway obstruction, chronic intermittent hypoxia and sleep fragmentation. OSA is well known to be associated with hypoxia, insulin resistance and glucose intolerance, and these factors can occur in the presence or absence of obesity and metabolic syndrome. Although it is well established that insulin resistance, glucose intolerance and obesity occur frequently with non-alcoholic fatty liver disease (NAFLD), it is now becoming apparent that hypoxia might also be important in the development of NAFLD, and it is recognized that there is increased risk of NAFLD with OSA. This review discusses the association between OSA, NAFLD and cardiovascular disease, and describes the potential role of hypoxia in the development of NAFLD with OSA.

Diurnal changes in retinal nerve fiber layer thickness with obstructive sleep apnea/hypopnea syndrome

AIM:To compare the retinal nerve fiber layer(RNFL)thickness in the morning and evening in Thai patients with varying degrees of obstructive sleep apnea/hypopnea syndrome(OSAHS).METHODS:In this cross-sectional study,potential OSAHS patients at Siriraj Hospital underwent polysomnography to determine the severity of OSAHS and an eye examination(including best corrected visual acuity,slit-lamp examination,and Goldmann applanation tonometry).RNFL thickness was recorded once in the morning and once in the evening,using spectral domain optical coherence tomography.Thickness was expressed as an average and given for each quadrant.Patients with ocular or systemic diseases that might affect RNFL thickness were excluded.RESULTS:Forty-one eyes of 41 patients were classified into 4 OSAHS groups.The average and mean RNFL thickness in most of the four quadrants of the severe OSAHS group trended toward being less than those in the comparable quadrants of the other groups in both the morning and evening.In the moderate OSAHS group,the average RNFL thickness and temporal and superior quadrant thickness in the morning were significantly higher than in the evening(P=0.01,P=0.01,and P=0.03,respectively).In the severe OSAHS group,the inferior quadrant thickness in the morning was significantly higher than in the evening(P=0.03).CONCLUSION:The RNFL thickness in the morning was higher than in the evening in moderate OSAHS.

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.

Correlation between metabolic syndrome and sleep apnea

The so-called "metabolic syndrome"(MS),constitutes a cluster of metabolic and cardiovascular abnormalities,including fasting glucose,blood pressure,triglycerides,high density lipoprotein cholesterol(HDL-C),and waist circumference that arise from insulin resistance. Obstructive sleep apnea(OSA) syndrome is characterized by recurrent episodes of partial or complete obstruction of the upper airway,involving cessation or significant decreased airflow,with intermittent hypoxemia,frequent arousals from sleep and recurrent oxyhemoglobin desaturations that interfere with normal sleep patterns generating difficulty falling asleep,unrefreshing sleep and loud snoring. The relation between these two entities is known as "Syndrome Z",and there is no question about the impact of these risk factors on health and disease. This clinical condition presents a growing epidemic Worldwide,affecting approximately 60% of the general population with both MS and OSA due to the constant increase of body mass index in humans. This article presents evidence-based data that focuses on the direct relationship between MS and OSA.

COGNITIVE AND EMOTIONAL IMPAIRMENT IN OBSTRUCTIVE SLEEP APNEA SYNDROME

Objective To evaluate the emotional and cognitive status in patients with obstructive sleep apnea syndrome (OSAS), using neuropsychological tests and evoked-related potential (P3). Methods Sixteen patients diagnosed of OSAS were tested by Hamilton rating scale for anxiety (HRSA) and Hamilton rating scale for depression (HRSD). Other three groups, OSAS patient group (n=21), snoring group (n=21), and control group (n=21), were administered polysomnography (PSG), auditory evoked event-related potential (P3), and clinic memory test. The results were analyzed using general linear model (GLM) analysis and Post Hoc test. Results Twelve OSAS patients’ scores of HRSA and HRSD were beyond the normal range, 26.42 ±4.48 and 22.08 ±3.97 respectively. The auditory P3 latency in OSAS group was 363.1 ±22.9 ms (Fz), 368.57 ±28.03 ms (Cz), in snoring group 336.57 ±31.08 ms (Fz), 339.81 ±31.76 ms (Cz), in control group 340.8 ±28.7 ms (Fz), 338.29 ±29.21 ms (Cz). There were significant differences between OSAS group and snoring group, as well as control group (P< 0.05). No significant difference was seen between snoring group and control group. No significant difference was noted in P3 amplitude among three groups. Memory quotient (MQ) reduced in snoring group compared with control group. Conclusions Emotional disturbances are common clinical features in OSAS patients. Abnormal auditory P3 latency indicates the cognitive dysfunction in OSAS patients. Nocturnal hypoxaemia may play an important role on it. Snorers should be monitored because of the tendency to develop cognitive impairment.

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(Hcy)as markers of cardiovascular and cerebrovascular 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 spectrophotometer.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.

Clinical observation of soft palate-pharyngoplasty in the treatment of obstructive sleep apnea hypopnea syndrome in children

BACKGROUND Childhood obstructive sleep apnea hypopnea syndrome(OSAHS)is a common clinical disease that can cause serious complications if not treated in time.The preferred treatment for OSAHS in children is surgery.AIM To observe the effects of soft palate-pharyngoplasty on postoperative outcome,pharyngeal formation,and possible complications.METHODS A total of 150 children with snoring,hernia,and mouth breathing were selected.A polysomnography test was performed to confirm the diagnosis of OSAHS.The children were randomly divided into experimental and control groups.The experimental group underwent adenoidectomy,tonsillectomy,and soft palatepharyngoplasty.The control group underwent adenoidectomy and tonsillectomy.The t-test and chi-square test were used to compare conditions such as postoperative fever,postoperative hemorrhage,and pharyngeal reflux.Postoperative efficacy and complications were interrogated and observed in the form of outpatient follow-up and telephone follow-up at 6 mo and 1 year after surgery.The curative effects were divided into two groups:Cure(snoring,snoring symptoms disappeared)and non-cure.RESULTS The effective rate of the experimental group was significantly higher than that of the control group,but the difference was not statistically significant(P>0.05).The incidence of postoperative bleeding was lower in the experimental group.There was no postoperative pharyngeal reflux in either group.In the experimental group,the incidence of hyperthermia(body temperature exceeded 38.5°C)was lower than that in the control group.The difference in postoperative swallowing pain scores between the experimental and control groups was significant.CONCLUSION Soft palate-pharyngoplasty can more effectively enlarge the anteroposterior diameter and transverse diameter of the isthmus faucium.Compared with surgery alone,it can better treat OSAHS in children,improve the curative effect,reduce the risk of perioperative bleeding,close the surgical cavity,reduce the risk of postoperative infection,reduce the proportion of postoperative fever,and accelerate healing.Although this process takes more time,it is simple,safe,and effective.

The Diagnosis Value and Its Implication of Impulse Oscillometry in Obstructive Sleep Apnea Syndrome Patients

The change of measurements of impulse oscillometry (105) in obstructive sleep apnea syn- drome (OSAS) patients and its mechanism were observed. The respiratory impedance was measured by using IOS technique and polysomnography (PSG) was monitored synchronously in 36 OSAS pa- tients,14 patients with chronic obstructive pulmonary disease (COPD) and 12 normal controls. Re- sults showed that R20 in OSAS group was significantly higher than in COPD group and control group (P<0.01). R5-R20 in OSAS group was lower than that in COPD group, but significantly higher than that in control group(P<0. 01). The levels of R20 and R5-R20 were positively correlated with severity degree of the disease. In addition, apnea-hyponea index (AHI) was positively correlated with R5 and R20 with the correlation index (r)being 0. 66 and 0. 86 respectively. The lowest SO2 was negatively correlated with R5 and R5-R20, with r being-0. 66 and- 0. 79 respectively. The mean SO2 was negatively correlated with R5 and R5-R20 with r being-0. 81 and-0. 69 respectively. IOS technique could be used as a valuable tool for assessing the degree of upper airway obstruction in the patients with OSAS, and could help to explore its pathological mechanism.

NoSAS评分在识别深度镇静支气管镜检查期间低氧血症高风险群体中的应用

目的 探索NoSAS评分在识别深度镇静支气管镜检查期间低氧血症高风险群体中的应用价值。方法 选择接受深度镇静支气管镜检查的293例患者作为研究对象。据NoSAS评分标准分为阻塞性睡眠呼吸暂停综合征(OSAS)高风险组和低风险组。比较两组患者在深度镇静支气管镜期间低氧血症等心肺不良事件的发生率和气道干预率。对发生低氧血症的影响因素进行单因素分析和多因素logistic回归分析。结果 与OSAS低风险组相比,高风险组发生低氧血症、严重低氧血症、气道干预(托下颌、提高氧流量、储氧面罩通气)的频率更高,差异均有统计学意义(χ~2分别=8.47、5.51、14.36、4.52、8.48,P均<0.05)。logistic多因素分析显示OSAS高风险组较低风险组显著增加深度镇静支气管镜检查期间发生低氧血症的风险(OR=2.38,95%CI 1.28~4.43,P<0.05)。结论 NoSAS评分有助于识别深度镇静支气管镜检查期间发生低氧血症高风险的群体,为预防及干预低氧血症提供重要依据。

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.

Stem/progenitor cells and obstructive sleep apnea syndrome - new insights for clinical applications

Obstructive sleep apnea syndrome(OSAS) is a widespread disorder, characterized by recurrent upper airway obstruction during sleep, mostly as a result of complete or partial pharyngeal obstruction. Due to the occurrence of frequent and regular hypoxic events, patients with OSAS are at increased risk of cardiovascular disease, stroke, metabolic disorders, occupational errors, motor vehicle accidents and even death. Thus, OSAS has severe consequences and represents a significant economic burden. However, some of the consequences, as well as their costs can be reduced with appropriate detection and treatment. In this context, the recent advances that were made in stem cell biology knowledge and stem cell- based technologies hold a great promise for various medical conditions, including respiratory diseases. However, the investigation of the role of stem cells in OSAS is still recent and rather limited, requiring further studies, both in animal models and humans. The goal of this review is to summarize the current state of knowledge regarding both lung resident as well as circulating stem/progenitor cells and discuss existing controversies in the field in order to identify future research directions for clinical applications in OSAS. Also, the paper highlights the requisite for inter-institutional, multi-disciplinary research collaborations in order to achieve breakthrough results in the field.

Serum Level of Vascular Endothelial Growth Factor in Patients with Obstructive Sleep Apnea Hypopnea Syndrome

To explore the relationship between the serum vascular endothelial growth factor (VEGF) level and the severity of obstructive sleep apnea hypopnea syndrome (OSAHS), the concentrations of serum VEGF in 40 OSAHS patients and 9 healthy controls were measured by using ELISA method. Meanwhile the correlation between the concentration of VEGF and parameters of polysomnography (PSG) was examined. Our results showed that the concentrations of VEGF were significantly higher in OSAHS patients with severe hypoxia (536.8±334.7 pg/mL) than in those with mild hypoxia (329.2±174.7 pg/mL) and healthy controls (272. 8±211.0 pg/mL) (P<0.05 for both). The concentra- tions of VEGF were also significantly higher in OSAHS patients with hypertension (484.5±261.4 pg/mL) than in those without hypertension (311.0±158.4 pg/mL) and healthy controls (272. 8± 211.0 pg/mL) (P<0.05 for both). There was a positive correlation between the concentration of VEGF and the apnea hypopnea index (AHI) (r=0.34, P<0.05). It is concluded that the concentration of the serum VEGF is positively related to the severity of OSAHS. The elevated serum VEGF level may be involved in the pathogenesis of the complications of obstructive sleep apnea hypopnea syndrome.

Management of non-alcoholic fatty liver disease patients with sleep apnea syndrome

Nonalcoholic fatty liver disease(NAFLD)is strongly associated with sleep apnea syndrome(SAS).Many NAFLD patients have SAS,and obstructive sleep apnea hypopnea syndrome is also considered to be an independent risk factor for NAFLD,as it contributes to the progression of NAFLD via oxidative stress,lipid peroxidation,inflammation,and insulin resistance.This review aims to provide some recommendations for the management of NAFLD patients with SAS,including diet,exercise,weight loss,and continuous positive airway pressure.This review also highlights the importance of effective strategies in NAFLD prevention and treatment.

Changes in Plasma Angiotensin II and Circadian Rhythm of Blood Pressure in Hypertensive Patients with Sleep Apnea Syndrome Before and After Treatment

Objective To explore the changes in plasma angiotensin II (Ang II) and circadian rhythm of blood pressure among hypertensive patients with sleep apnea syndrome (SAS) before and after continuous positive airway pressure (CPAP) or surgical treatment.Methods A total of 180 essential hypertension patients were enrolled in our study.The determination of plasma Ang II concentration,ambulatory blood pressure (ABP),and polysomnography (PSG) monitoring were performed before and 3 months after CPAP or surgical treatment.Results Patients were classified into three groups by their apnea-hypopnea index (AHI):essential hypertension group (EH group,n=72;AHI<5),essential hypertension with mild SAS group (EH+mild SAS group,n=60,5≤AHI<20),and essential hypertension with moderate and severe SAS group (EH+moderate-severe SAS group,n=48,AHI≥20).The concentrations of plasma AngⅡ in the above three groups were 13.42±3.27,16.17±3.82,and 18.73±4.05 ng/mL respectively before treatment,and AngⅡ concentration in EH patients combined with SAS was significantly higher than that in EH group (all P<0.05).After treatment the values in the latter two groups significantly decreased to 14.67±2.56 and 15.03±3.41 ng/mL respectively (P<0.05).The incidence of non-dipper blood pressure curve in EH patients was 31.9%,and those in hypertensive patients with mild SAS and moderate-severe SAS were 51.7% and 58.3%,respectively before treatment.The incidence of non-dipper blood pressure curve in the EH patients with mild SAS was significantly higher than that of patients with EH alone (P<0.05).After CPAP treatment or surgery,the incidence of non-dipper blood pressure curve in the two SAS groups was significantly decreased to 38.3% and 39.6%,respectively (P<0.05).Conclusions Ang II might play a role in blood pressure variability in patients with obstructive SAS.CPAP or surgical treatment can improve blood pressure disorder and decrease plasma Ang II level in patients with obstructive SAS.

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 Montreal 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.

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 obstructive 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 performed 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 involving 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.