Idiopathic edema is associated with obstructive sleep apnea in women

BACKGROUND AND PURPOSE: This study was undertaken to clarify whether idiopathic edema is a marker for obstructive sleep apnea (OSA), independent of level of obesity, in patients with normal left ventricular function. PATIENTS AND METHODS: Seventy-eight ambulatory, obese, adults, 44 with bilateral, pitting pre-tibial edema, and 34 without edema, from an inner city family practice and a suburban family practice enrolled from July 1995 until March 2003. Edematous subjects, but not non-edematous subjects, underwent echocardiography, urinalysis, and blood test evaluations to ensure that cardiac, renal, hepatic, and thyroid functions were normal. All subjects underwent spirometry, pulse oximetry on room air, and polysomnography evaluations. RESULTS: Compared to the non-edematous subjects, the edematous subjects were more obese (body mass index=47.0+/-9.3 versus 36.5+/-4.6 kg/m2, P=0.002), had more severe OSA (apnea-hypopnea index (AHI)=34.1+/-27.7 versus 17.0+/-19.4, P=0.002), and had lower oxygen saturations (96.2+/-2.0 versus 97.1+/-1.5%, P=0.05). Using an AHI > or = 15 as the criteria for diagnosing OSA, there was an association between edema and OSA in women (P=0.02) but not men. CONCLUSIONS: In subjects with normal left ventricular function, idiopathic edema is associated with OSA in women.     

Severity of individual obstruction events increases with age in patients with obstructive sleep apnea

BackgroundAge is a risk factor of obstructive sleep apnea (OSA). It has been shown that OSA progresses over time, although conflicting results have been reported. However, the effect of age on the severity of OSA and individual obstruction events has not been investigated within different OSA severity categories by taking the most prominent confounding factors (i.e., body mass index, gender, smoking, daytime sleepiness, snoring, hypertension, heart failure, and proportion of supine sleep) into account.MethodsPolygraphic data of 1090 patients with apnea–hypopnea index (AHI) ≥5 were retrospectively reanalyzed. The effect of age on the severity of OSA and obstruction events was investigated in general, within different OSA severity categories, and in different age groups (age <40, 40≤ age <50, 50≤ age <60, and age ≥60 years).ResultsIn the whole population, AHI and durations of apneas, hypopneas, and desaturations increased with increasing age (B ≥ 0.108, p ≤ 0.010). In more detailed analysis, AHI increased with age only in the moderate OSA category (B = 0.075, p = 0.022), although durations of apneas increased in mild and severe OSA categories (B ≥ 0.076, p ≤ 0.038). Furthermore, durations of hypopneas increased with age in mild and moderate OSA categories (B ≥ 0.105, p ≤ 0.038), and durations of desaturations (B ≥ 0.120, p ≤ 0.013) in all OSA severity categories. AHI was not statistically significantly different between the age groups, although durations of obstruction events tended to increase towards older age groups.ConclusionAs obstruction event severity was more strongly dependent on the age than it was dependent on AHI, considering the severity of obstruction events could be beneficial while estimating the long-term effects of the treatments and prognosticating the disease progression.     

Association of cervical spondylosis with obstructive sleep apnea

ObjectiveThe study objective was to evaluate the association between cervical spondylosis (CS) and a subsequent diagnosis of obstructive sleep apnea (OSA) in light of the expected constricting impact of CS-associated cervical spine changes on the pharyngeal airway space, a key contributor to OSA.MethodsData were retrieved from the Taiwan National Health Insurance Research Dataset. A total of 98,234 patients who newly received a diagnosis of OSA were identified. We identified four propensity score-matched controls per OSA patient (n = 392,936). Chi-square tests were used to compare cases and controls on sociodemographic characteristics, and multivariable logistic regression modelling to examine the association of OSA with prior CS.ResultsOf the 98,234 sampled patients, 18,070 (18.4%) patients had a prior CS diagnosis, significantly different among cases compared to controls, being 18.4% and12.1%, respectively, p < 0.001. Logistic regression analysis showed an adjusted odds ratio (OR) of prior CS of 1.778 (95% confident interval (CI): 1.744–1.814) relative to controls. The adjusted odds of prior CS without myelopathy was 1.764 for cases relative to controls (95% CI: 1.727–1.801), and for prior CS with myelopathy (adjusted OR: 1.778, 95% CI: 1.721–1.837). Analysis stratified by age showed that in the 45–64- and >64-year age groups, the adjusted ORs of CS were 1.803 (95% CI: 1.758–1.850) and 1.634 (95% CI: 1.568–1.703), respectively, for cases relative to controls.ConclusionsOur results suggest that OSA is associated with prior CS. The results call for professionals to be alert to the possibility of subsequent development of OSA among patients with CS.     

Comparison of obstructive sleep apnea patients with and without leg edema

BackgroundTo determine the proportion of patients with obstructive sleep apnea (OSA) who have leg edema, and to identify differences between edematous and non-edematous OSA patients.MethodsRetrospective, cross-sectional study of 378 patients with OSA (apnea/hypopnea index [AHI] ⩾15) who had neither heart failure nor chronic lung disease.ResultsThirty-five percent (133/378) of the subjects with OSA had bilateral leg edema. Eighty-one percent (108/133) of the edematous subjects had mild pitting that was 1+. Compared to the non-edematous OSA subjects, the edematous subjects were older (age = 51 ± 13 versus 45 ± 13 years, p = 0.001), more obese (body mass index = 39 ± 9 versus 33 ± 8 kg/m², p = 0.001), had more severe OSA (AHI = 46 ± 71 versus 27 ± 29, p = 0.004), spent a greater proportion of sleep time with an oxygen saturation <90% (20 ± 26 versus 11 ± 18%, p = 0.001), and were more likely to have diabetes mellitus (11% versus 3%, p = 0.001) and hypertension (32% versus 10%, p = 0.001). Age, obesity, hypertension and diabetes mellitus correlated significantly with edema status. After adjusting for these confounding variables, the AHI means remained different between the edema and non-edema groups (41 ± 5 versus 28 ± 3, p = 0.04).ConclusionsApproximately one-third of OSA patients have edema. Edematous OSA patients are older, more obese, more likely to have diabetes mellitus and hypertension, and have more severe OSA than OSA patients who lack edema.     

Visual vigilance in drivers with obstructive sleep apnea

Objective

To determine the effects of obstructive sleep apnea (OSA) on visual vigilance during simulated automobile driving.

Methods

Twenty-five drivers with OSA and 41 comparison drivers participated in an hour-long drive in a high-fidelity driving simulator. Drivers responded to light targets flashed at seven locations across the forward horizon. Dependent measures were percent correct [hit rate (HR)] and reaction time (RT). Self-assessment of sleepiness used the Stanford Sleepiness Scale (SSS) before and after the drive and the Epworth Sleepiness Scale (ESS).

Results

OSA drivers showed reduced vigilance based on lower HR than comparison drivers, especially for peripheral targets (80.7±14.8% vs. 86.7±8.8%, P=.03). OSA drivers were sleepier at the end of the drive than comparison drivers (SSS=4.2±1.2 vs. 3.6±1.2, P=.03), and increased sleepiness correlated with decreased HR only in those with OSA (r=−0.49, P=.01). Lower HR and higher post-drive SSS predicted greater numbers of driving errors in all subjects. Yet, ESS, predrive SSS, and most objective measures of disease severity failed to predict driving and vigilance performance in OSA.

Conclusions

Reduced vigilance for peripheral visual targets indicates that OSA drivers have restriction of their effective field of view, which may partly explain their increased crash risk. This fatigue-related decline in attention is predicted by increased subjective sleepiness during driving. These findings may suggest a means of identifying and counseling high-risk drivers and aid in the development of in-vehicle alerting and warning devices.     

The effect of aging and severity of sleep apnea on heart rate variability indices in obstructive sleep apnea syndrome

Objective

This study aims to analyze how much heart rate variability (HRV) indices discriminatively respond to age and severity of sleep apnea in the obstructive sleep apnea syndrome (OSAS).

Methods

176 male OSAS patients were classified into four groups according to their age and apnea-hypopnea index (AHI). The HRV indices were compared via analysis of covariance (ANCOVA). In particular, the partial correlation method was performed to identify the most statistically significant HRV indices in the time and frequency domains. Stepwise multiple linear regressions were further executed to examine the effects of age, AHI, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), and sleep parameters on the significant HRV indices.

Results

The partial correlation analysis yielded the NN50 count (defined as the number of adjacent R-wave to R-wave intervals differing by more than 50 ms) and low frequency/high frequency (LF/HF) ratio to be two most statistically significant HRV indices in both time and frequency domains. The two indices showed significant differences between the groups. The NN50 count was affected by age (p<0.001) and DBP (p=0.039), while the LF/HF ratio was affected by AHI (p<0.001), the amount of Stage 2 sleep (p=0.005), and age (p=0.021) in the order named in the regression analysis.

Conclusion

The NN50 count more sensitively responded to age than to AHI, suggesting that the index is mainly associated with an age-related parasympathetic system. On the contrary, the LF/HF ratio responded to AHI more sensitively than to age, suggesting that it is mainly associated with a sympathetic tone likely reflecting the severity of sleep apnea.     

Age-specific markers of adiposity in patients with obstructive sleep apnea

ObjectivesAdiposity can have varying effects on the individual depending upon its distribution pattern. We assessed age-related distribution of adipose tissue by anthropometric measures and bioelectrical impedance analysis, as well as their association with obstructive sleep apnea (OSA) severity.MethodsParticipants were 169 elderly (aged ≥ 65 years) and 142 non-elderly (aged < 65 years) referred for overnight polysomnography. The associations between obesity parameters and apnea-hypopnea index (AHI) were determine by univariate and multivariate linear regression analyses. Area under receiver operating characteristic curve (AUC) was used to access the predicting performance of some parameters.ResultsCompared with non-elderly, elderly showed higher conicity index and visceral adiposity (VA)/subcutaneous adiposity (SA), lower body mass index (BMI), neck circumference, waist circumference, hip circumference and SA. Multiple regression analyses revealed that VA and VA/SA were independently associated with AHI in elderly (explained 17.2% of the AHI ^0.5 variability), while BMI and VA/SA were independently associated with AHI in non-elderly (explained 25.9% of the AHI ^0.5 variability), after adjusting for age, sex, cigarette smoking, alcohol drinking and main comorbidities. In elderly, VA over 128 cm² and VA/SA less than 0.41 resulted in sensitivity, specificity and AUC of 0.382, 0.790, 0.580 and 0.176, 0.947, 0.553 in predicting moderate-to-severe OSA, respectively. In non-elderly, BMI over 24.7 kg/m² and VA/SA over 0.54 resulted in sensitivity, specificity and AUC of 0.883, 0.484, 0.704 and 0.550, 0.710, 0.667 in predicting moderate-to-severe OSA, respectively.ConclusionsVA is strongly associated with OSA severity in elderly, independently of general obesity as per BMI standards, while general adiposity appears to be more strongly associated with OSA severity in non-elderly. Our study supports age-specific approaches should be developed with respect to prediction and treatment of OSA.     

Sleep and libido in men with obstructive sleep apnea syndrome

ObjectivesThe objectives of this study were to investigate the relationship between a low libido and objective sleep parameters as well as mood disturbances in patients with obstructive sleep apnea syndrome (OSA).MethodsWe enrolled 436 untreated patients who were newly diagnosed with OSA (all male, mean age 42.8 years). Patients completed the Symptom checklist-90-Revised (SCL-90-R), Epworth Sleepiness Scale (ESS), Beck Depression Inventory-II (BDI), and Beck Anxiety Inventory (BAI). Patients were divided into low-libido and normal-libido groups according to their response to the statement “Loss of sexual interest or pleasure” on the SCL-90-R.ResultsApproximately 23% of patients reported a low libido. Patients with a low libido were older (47.5 ± 9.0 vs. 41.4 ± 11.1 years; p < 0.001), had more nocturia (33.3% vs. 16.6%; p < 0.001), higher BDI (9.0 (5.0–14.0) vs. 5.0 (2.0–9.0); p < 0.001) and BAI score (11.0 (6.3–16.8) vs. 5.0 (2.0–10.0); p < 0.001). These patients had a lower non-REM sleep stage 3 (N3) % (0.1 (0–4.0) vs. 2.3 (0.1–7.9); p < 0.001). Multivariate analysis revealed that older age and higher BDI score were independent factors associated with a low libido.ConclusionsMen with untreated OSA suffered from a low libido. Older age and depressed mood were the most important factors of low libido in middle-aged men with OSA.     

Hippocampal area metabolites relate to severity and cognitive function in obstructive sleep apnea

BACKGROUND AND PURPOSE: Obstructive sleep apnea (OSA) is associated with intermittent hypoxia and cognitive decrements. As the hippocampus is particularly susceptible to hypoxia, we hypothesized that it may show biochemical abnormalities, and they may relate to apnea severity. PATIENTS AND METHODS: Eight males with OSA and five age-matched controls underwent neurocognitive testing before and after polysomnography and proton magnetic resonance spectra were obtained from the left hippocampal area of all subjects. RESULTS: In the left hippocampal area, N-acetyl-containing/creatine-containing compounds was significantly increased in OSA (P=0.04). Inspection of these compounds with respect to the water resonance indicated that this was most likely due to a decrease in creatine-containing compounds rather than any change in N-acetyl-containing compounds. Lower levels of hippocampal creatine-containing compounds were correlated with worse OSA severity and neurocognitive performance. CONCLUSIONS: We suggest the changes in creatine levels in the hippocampal area represent adjustments to brain bioenergetics, similar to those seen in ischemic preconditioning, and may reflect the different susceptibility of these tissues to hypoxic damage in OSA.     

SIESTA - Home sleep study with BresoDx for obstructive sleep apnea: a randomized controlled trial

Study objectivesThe objectives of this study were to evaluate (1) the accuracy of the clinical diagnosis of obstructive sleep apnea (OSA) informed by the home sleep study with a Type 4 portable monitor BresoDx® versus Type 1 polysomnography (PSG); and (2) agreement of the apnea-hypopnea index (AHI) compared between BresoDx and PSG.Material and methodsThis was a randomized, parallel, multicentre, single-blind, pragmatic controlled trial enrolling adults referred to three Ontario sleep clinics for suspected OSA. Participants were randomized to BresoDx followed by PSG (one-night apart) or PSG followed by BresoDx sleep testing sequence arms. The primary outcomes included the accuracy of clinical diagnosis and OSA severity measured by AHI between tests.ResultsIn sum, 233 participants completed both sleep studies and 206 completed physician consultation visits. The agreement between clinical diagnosis informed by PSG versus BresoDx was fair (Cohen's kappa coefficient = 0.28). The sensitivity of BresoDx-informed clinical diagnosis against PSG was between 0.86 and 0.89, and the specificity between 0.38 and 0.44. For AHI cut-off of ≥5 events/hour the sensitivity, specificity and positive and negative predictive values were 0.85, 0.48, 0.81 and 0.54.ConclusionsHome sleep apnea testing with BresoDx can be used in a referral population with a high pretest probability of OSA similar to other Type IV devices. This study complements the existing body of evidence suggesting that home testing with portable devices plays a valuable role for diagnosing of OSA in a variety of settings.SIESTA trial registrationwww.clinicaltrials.gov (Identifier: NCT02003729).     

阻塞性睡眠呼吸暂停低通气综合征及脑卒中与认知功能障碍的关系

阻塞性睡眠呼吸暂停低通气综合征（OSAHS）是脑卒中的危险因素,脑卒中患者合并阻塞性睡眠呼吸暂停在流行病学上也远远高于普通人群的发病率.OSAHS及脑卒中都可以发生认知功能障碍,两者并存有可能加剧患者认知功能障碍程度及影响恢复,研究和了解OSAHS对卒中后认知功能的影响,对卒中相关认知障碍的防治有着重要的意义.     

Effects of an individualized exercise training program on severity markers of obstructive sleep apnea syndrome: a randomised controlled trial

ObjectiveObstructive sleep apnea (OSA) is a high prevalent disorder with severe consequences including sleepiness, metabolic, and cardiovascular disorders. The aim of this study was to assess the effect of an individualized exercise-training (IET) program with educational sessions vs educational sessions alone on severity markers of OSA over an eight-week duration.MethodsThis was a randomised, controlled, parallel-design study. In sum, 64 patients with moderate-to-severe OSA (apnea-hypopnea index AHI 15–45/hour), low physical activity level (Voorrips<9), body-mass index (BMI) <40 kg/m² were included in intervention group (IG) or control group (CG), and 54 patients finished the study. All underwent polysomnography (PSG), multiple sleep latency test (MSLT), constant workload exercise test, blood samples and fulfilled questionnaires twice. The primary endpoint was the change in apnea-hypopnea (AHI) at eight weeks from baseline. Main secondary endpoints were daytime sleepiness assessed by questionnaire and objective tests.ResultsNo significant between-group differences were found for changes in AHI. A reduction in AHI was found in IG only (p = 0.005). Compared to CG, exercise training leads to a greater decrease in AHI during REM sleep (p = 0.0004), with a significant increase in mean daytime sleep latency (p = 0.02). Between-group differences were significant for weight reduction, severity of fatigue, insomnia and depressive symptoms with trend for sleepiness symptoms.ConclusionsIn adult patients with moderate-to-severe OSA, IET did not decrease AHI compared to the control group but improved markers of severity of OSA, in particular AHI in rapid eye movement (REM) sleep and objective daytime sleepiness. Adding personalized exercise training to the management of patients with OSA should be considered.ClinicalTrials.gov identifierNCT01256307.     

阻塞性睡眠呼吸暂停综合征患者事件相关电位研究

目的　研究阻塞性睡眠呼吸暂停患者事件相关电位Ｐ３ 的变化,探讨可能的机制。方法　入组受试者分为阻塞性睡眠呼吸暂停患者组（ｎ ＝ ３０） 及正常对照组（ｎ ＝ ３０） ,均进行睡眠多导仪、听觉诱发事件相关电位（Ｐ３） 、临床记忆量表检查及神经系统查体。结果采用ｔ 检验和Ｓｐｅａｒｍａｎ 等级相关分析。结果　阻塞性睡眠呼吸暂停患者组记忆商（ＭＱ）为９０ ±１２ ,Ｐ３ 潜伏期为（３５９±３０） 毫秒（Ｆｚ 记录点） ,（３６５±３１） 毫秒（Ｃｚ 记录点） ;正常对照组ＭＱ为１０４±１６,Ｐ３ 潜伏期为（３３７±２９） 毫秒（Ｆｚ记录点） ,（３３９±３１）毫秒（Ｃｚ 记录点） 。阻塞性睡眠呼吸暂停患者组与正常对照组的Ｐ３ 潜伏期和记忆商差异存在显著性意义（Ｐ＜ ０．０５）。结论　阻塞性睡眠呼吸暂停患者有认知功能损害,夜间低氧血症可能起重要作用。     

Treatment of snoring and obstructive sleep apnea with mandibular repositioning appliances

Snoring and obstructive sleep apnea form part of a spectrum of sleep disordered breathing affecting a significant proportion of the general population and particularly the middle aged. The consequences can be severe and even life threatening for both the individual directly affected and those more remotely involved. Adverse sequelae can manifest themselves acutely or in the longer term as a result of obstructive breathing induced hypersomnolence, neurocognitive deficits and cardiovascular abnormalities. The combination of anatomical and neuromuscular risk factors in the pathogenesis of OSA has resulted in a varied approach to its management. One such treatment option is mandibular repositioning appliances (MRA), which mechanically stabilize the airway. Whilst the efficacy of this simple intervention has been rigorously proven quite recently in a significant proportion of patients with varying disease severity, individual patient selection in its application remains uncertain. Short-term side-effects are common but usually transient, whilst in the long-term minor permanent adverse developments on the dentition and occlusion have been reported. Considering both the medicolegal implications of snoring and OSA and the increasing popularity of MRA, it is recommended that skilled multidisciplinary respiratory and dental personnel form the primary care team.     

Molecular determinants of obstructive sleep apnea

Obstructive sleep apnea (OSA) is characterized as recurrent episodes of obstruction in the upper airway during the period of sleep. The condition occurs in approximately 11% and 4% of middle-aged men and middle-aged women, respectively. Polysomnography is a diagnostic procedure that involves the constant observation of oxygen saturation and unsaturation during sleep. Usually, positive airway pressure is considered a benchmark treatment for OSA.This review summarizes the recent developments and emerging evidence from molecular biology-based research studies that show that genetic factors have an influence on OSA. The genetic aspects of OSA that have been identified include heritability and other phenotypic co-factors such as anatomical morphology. It also draws attention to the results of a polymorphic-based study that was conducted to determine the causative single nucleotide mutations associated with obesity and adverse cardiovascular risk in OSA. However, the role of such mutations and their linkage to OSA can not yet be established. Nonetheless, a large body of evidence supports a strong association between inflammatory cytokine polymorphism and obesity in the development of OSA. There are also probable intermediate factors with several gene–gene interactions. Therefore, advanced applications and modern techniques should be applied to facilitate new findings and to minimize the risk of developing OSA.     

Postprandial hyperglycemia in type 2 diabetes and obstructive sleep apnea

ObjectivesPostprandial hyperglycemia is common in type 2 diabetes even in those with acceptable glycemic control and conveys an increased risk of cardiovascular morbidity and mortality. Although obstructive sleep apnea (OSA) has been associated with altered glucose metabolism, data regarding its association with postprandial hyperglycemia in type 2 diabetes are limited. Thus, the current study sought to characterize the association between OSA and postprandial hyperglycemia in adults with type 2 diabetes.MethodsA cross-sectional study of adults with type 2 diabetes was conducted. Home sleep testing was used to assess OSA severity as determined by the oxygen desaturation index (ODI). Self-monitoring of blood glucose (SMBG) was performed before and 2-h after breakfast, lunch, and dinner for three days. The association between OSA and glucose levels before and after each meal was examined using multivariable logistic regression.ResultsThe study sample consisted of 195 adults with 52% being men. OSA severity, as assessed by ODI quartiles, was associated with higher postprandial glucose values after dinner but not after breakfast or lunch. The adjusted odds ratios (95% confidence intervals) for a higher post-dinner glucose level for four ODI quartiles were 1.00 (Reference), 2.16 (0.96, 4.87), 2.23 (1.03, 4.83), and 2.58 (1.18, 5.94). Stratified analyses showed that this association was present in men but not women.ConclusionsIncreasing OSA severity is associated with postprandial hyperglycemia in type 2 diabetes and may contribute to impaired glycemic control. Future studies examining the impact of OSA treatment on glucose metabolism should consider meal-related glycemic excursions as a potential outcome.     

原发性癫痫合并阻塞性睡眠呼吸暂停低通气综合征的临床特点

目的探讨原发性癫痫合并阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者的临床特点。方法回顾性分析2007-06-2014-06在我院确诊的16例原发性癫痫合并OSAHS患者的临床资料(包括病史、多导睡眠脑电图及治疗随访)。结果癫痫形式表现为全面强直阵挛发作13例,部分性发作3例,其中夜间发作11例,白天发作5例;多导睡眠脑电图(polysomnography,PSG)显示均为阻塞性睡眠呼吸暂停低通气综合征(OSAHS),其中重度9例,中度4例,轻度3例。所有患者经抗癫痫药物治疗及OSAHS的指导性治疗。其中4例癫痫伴重度OSAHS经单纯药物治疗仍反复发作,联合丙戊酸钠和经鼻持续气道正压通气(CPAP)治疗,随访0.5~3a,发作频率减少3例,发作停止1例。结论原发性癫痫合并OSAHS一般以中老年男性多见,癫痫类型以夜间全面强直阵挛性发作为主,对于单纯抗癫痫药物治疗不佳者,药物联合CPAP治疗可取得明显效果。     

Alterations in sympathetic and parasympathetic brain networks in obstructive sleep apnea

Objective/backgroundObstructive sleep apnea (OSA) patients experience hypoxia and, potentially, autonomic impairments stemming from neural damage. In this study, the executive control networks (ECNs), salience networks (SNs), and default mode networks (DMNs) of adult OSA patients, as well as their relationships with autonomic impairment, were investigated through independent component analysis (ICA).Patients/methodsA total of 41 OSA patients and 19 healthy controls volunteers were recruited and subjected to polysomnography to ascertain their degree, if any, of sleep apnea. Each participant also underwent a cardiovascular autonomic survey, with the participant's baroreflex sensitivity (BRS) being determined based on heart rate and blood pressure alterations. The resting fMRI data of the participants was separated using probabilistic ICA, and six autonomic resting-state networks were established for group comparisons. The differences in autonomic parameters, autonomic functional connectivity (FC), and clinical severity were then correlated.ResultsThe OSA group had significantly worse BRS values than the controls, as well as lower FC in the posterior and anterior SNs, bilateral ECNs, and the ventral DMN, and higher FC in the left ECN. These intrinsic connectivity networks showed dissociable correlations with greater baroreflex impairment and clinical disease severity. The higher FC in the left ECN was associated with the lower FC in the ventral DMN.ConclusionsOur findings suggest that autonomic dysfunction in OSA might be accompanied by central autonomic network alterations. The stronger sympathetic-associated regions in ECNs and the weaker parasympathetic-associated regions in DMNs may represent intrinsic neural architecture fluctuations underlining their consequent processes in OSA.     

Moderate-to-severe obstructive sleep apnea is associated with cerebral small vessel disease

BackgroundCerebral small vessel disease (SVD) is associated with increased risk of cerebral infarction and hemorrhage. Obstructive sleep apnea (OSA) is known to increase the risk of cerebrovascular disease. This study aimed to investigate the association between cerebral SVD and severity of OSA.MethodsA total of 170 patients were included from the patient registry at the present Sleep Center; these patients underwent both magnetic resonance imaging (MRI) of the brain and polysomnography (PSG) for suspected OSA. The presence and burden of white matter hyperintensities (WMHs), asymptomatic lacunar infarctions (ALIs), cerebral microbleeds (CMBs), and perivascular spaces (PVSs) were determined by MRI, and their relationships with the apnea–hypopnea index (AHI), as determined by PSG, were investigated.ResultsAmong the 170 patients, 25 (14.7%) had high-grade WMHs, 21 (12.4%) had ALIs, 21 (12.4%) had CMBs, and 34 (20.0%) had high-grade PVSs. In the multivariable analysis, after adjusting for factors including age, sex, and other variables for which p <0.1 in univariable analysis (hypertension, diabetes mellitus, previous stroke, minimal SaO₂ and arousal index), moderate-to-severe OSA was associated with high-grade WMHs (odds ratio [OR] 4.72; 95% confidence interval [CI] 1.14–19.47), CMBs (OR 3.47; 95% CI 0.89–15.18), or high-grade PVSs (OR 3.64; 95% CI 1.02–13.01), but not with ALIs. The total SVD score was independently associated with increased AHI (p = 0.017), particularly in patients with moderate-to-severe OSA (β [standard error] = 0.448 (0.204), p = 0.030].ConclusionModerate-to-severe OSA is positively associated with multiple indicators of cerebral SVD, including WMHs, CMBs, and PVSs.