Predominant obstructive or central sleep apnea in patients with atrial fibrillation: influence of characterizing apneas versus apneas and hypopneas

Objective/backgroundSleep-disordered breathing (SDB) is common in patients with atrial fibrillation (Afib). Although a high proportion of respiratory events are hypopneas, previous studies have only used apneas to differentiate obstructive (OSA) from central (CSA) sleep apnea. This study investigated the impact of using apneas and hypopneas versus apneas only to define the predominant type of SDB in Afib patients with preserved ejection fraction.Patients/methodsThis retrospective analysis was based on high-quality cardiorespiratory polygraphy (PG) recordings (07/2007–03/2016) that were re-analyzed using 2012 American Academy of Sleep Medicine criteria, with differentiation of apneas and hypopneas as obstructive or central. Classification of predominant (>50% of events) OSA and CSA was defined based on apneas only (OSA_AI and CSA_AI) or apneas and hypopneas (OSA_AHI and CSA_AHI). SDB was defined as an apnea–hypopnea index ≥5/h.ResultsA total of 211 patients were included (146 male, age 68.7 ± 8.5 y). Hypopneas accounted for >50% of all respiratory events. Based on apneas only, 46% of patients had predominant OSA and 44% had predominant CSA. Based on apneas and hypopneas, the proportion of patients with OSA was higher (56%) and that with CSA was lower (36%). In the subgroup of patients with moderate to severe SDB (AHI ≥ 15/h), the proportion with predominant CSA was 55.2% based on apneas only versus 42.1% with apneas and hypopneas.ConclusionsIn hospitalized patients with Afib and SDB, use of apneas and hypopneas versus apneas alone had an important influence on the proportion of patients classified as having predominant OSA or CSA.     

Beclin-1 increases with obstructive sleep apnea severity

Obstructive sleep apnea is a common chronic disorder that leads to chronic intermittent hypoxia described as an important factor contributing to the pathogenesis of OSA-related comorbidities. Besides, recent data suggest that intermittent hypoxia can induce adaptative cardiovascular pathways inducing a relative resistance to ischemic insults. Adaptative pathways induced by hypoxia could implicate autophagic processes and Beclin-1, one of the first mammalian autophagy effectors. Thus, activation of autophagy could protect against cardiovascular events in patients with OSA and could be considered as biomarker of a better prognosis.     

The impact of obstructive sleep apnea and daytime sleepiness on work limitation

BACKGROUND: Many patients with obstructive sleep apnea (OSA) participate in the work force. However, the impact of OSA and sleepiness on work performance is unclear. METHODS: To address this issue, we administered the Epworth Sleepiness Scale (ESS), the Work Limitations Questionnaire (WLQ), and an occupational survey to patients undergoing full-night polysomnography for the investigation of sleep-disordered breathing. Of 498 patients enrolled in the study, 428 (86.0%) completed the questionnaires. Their mean age+/-standard deviation (SD) was 49+/-12 years, mean body mass index (BMI) was 31+/-7 kg/m(2) mean apnea hypopnea index (AHI) was 21+/-22 events/h, and mean ESS score was 10+/-5. Subjects worked a mean of 39+/-18 h per week. The first 100 patients to complete the survey were followed up at two years. RESULTS: In the group as a whole, there was no significant relationship between severity of OSA and the four dimensions of work limitation. However, in blue-collar workers, significant differences were detected between patients with mild OSA (AHI 5-15/h) and those with severe OSA (AHI>30/h) with respect to time management (limited 23.1% of the time vs. 43.8%, p=0.05) and mental/personnel interactions (17.9% vs. 33.0%, p=0.05). In contrast, there were strong associations between subjective sleepiness (as assessed by the ESS) and three of the four scales of work limitation. That is, patients with an ESS of 5 had much less work limitation compared to those with an ESS 18 in terms of time management (19.7% vs. 38.6 %, p<0.001), mental-interpersonal relationships (15.5% vs. 36.0%, p<0.001) and work output (16.8% vs. 36.0%; p<0.001). Of the group followed up, 49 returned surveys and 33 who were using continuous positive airway pressure (CPAP) showed significant improvements between the initial and second follow-up in time management (26% vs. 9%, p=0.0005), mental-interpersonal relationships (16% vs. 11.0%, p=0.014) and work output (18% vs. 10%; p<0.009). CONCLUSION: We have demonstrated a clear relationship between excessive sleepiness and decreased work productivity in a population referred for suspected sleep-disordered breathing. Screening for sleepiness and sleep-disordered breathing in the workplace has the potential to identify a reversible cause of low work productivity.     

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.     

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.     

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.     

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.     

Varenicline administration for smoking cessation may reduce apnea hypopnea index in sleep apnea patients

Objective/Background: Varenicline (VAR) is used for smoking cessation as it inhibits nicotine for binding on its receptors reducing nicotine dependence. VAR administration has been reported to affect sleep. The aim of this study was to evaluate possible changes in polysomnography (PSG) during VAR treatment (SmokeFreeBrain) in healthy smokers and smokers with obstructive sleep apnea (OSA). Patients/Methods: Thirty smokers (21 men) with 15.3 ± 10.2 PY, aged 32.8 ± 4.5 years, with BMI 28.6 ± 4 kg/m², 16 without and 14 with OSA (92% males) were studied with PSG (Embletta MPR-Master) before treatment with VAR while smoking and 20–30 days during VAR administration and smoking cessation for at least 5 days. Results: No significant differences were observed in sleep macro architecture (N1, N2, N3, REM, Sleep Efficiency, Total Sleep Time) during VAR treatment apart from prolongation of sleep latency, N2 and N3 latency in both smokers with and without OSA. Apnea hypopnea index (AHI) was reduced in OSA smokers and especially during REM with a borderline increase of arousal index (ArI) and reduction of sleep efficiency (SE). Conclusion: VAR treatment worsened sleep quality as a prolongation of sleep latency, N2 and N3 latency was observed. A marginal reduction of AHI was found in OSA patients, more significantly during REM. Due to the small sample size, further studies are needed to distinguish between the adverse reactions of VAR treatment and smoking cessation effects and to evaluate whether VAR may play a role in OSA treatment.     

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。     

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.     

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.     

阻塞型睡眠呼吸暂停综合征患者情绪障碍的研究进展

在临床中睡眠呼吸暂停综合征患者患抑郁、焦虑的概率较高,而且同时患有抑郁、焦虑及OSAS的患者比仅患有OSAS患者病情更重。尽管许多研究评估了OSAS与情绪障碍间的关系,OSAS及情绪障碍之间一些可能的因果机制也已被提出,但是OSAS在情绪障碍的因果关系仍不清楚。对于OSAS伴焦虑抑郁状态的患者,情绪障碍的干预治疗有助于改善OSAS患者的嗜睡、疲劳症状及认知功能,提高患者生活质量。     

伴中重度阻塞性睡眠呼吸暂停低通气综合征的抑郁症患者多导睡眠监测特点

目的 探讨伴中重度阻塞性睡眠呼吸暂停低通气综合征（OSAHS）的抑郁症患者多导睡眠监测（PSG）特点。方法 回顾性分析2017年12月-2019年10月在苏州市广济医院睡眠医学中心完成整夜多导睡眠监测（PSG）的门诊和住院患者以及健康体检人群,从中筛选出四组被试,分别为伴中重度OSAHS的抑郁症患者（n=31）、不伴OSAHS的抑郁症患者（n=79）、中重度OSAHS患者（n=96）和正常对照组（n=32）。比较四组被试睡眠进程相关指标（总睡眠时间、睡眠潜伏期、觉醒次数）和睡眠结构相关指标（N1、N2、N3期及REM期占总睡眠时间的比例,REM潜伏期、REM期持续时间）以及睡眠呼吸相关指标（氧减指数）等参数。结果 睡眠进程方面,四组被试总睡眠时间、睡眠潜伏期和觉醒次数差异均有统计学意义（F=2.874、3.959、12.291,P<0.05或0.01）。睡眠结构方面,四组被试N2期、N3期占总睡眠时间比例差异均有统计学意义（F=13.885、48.013,P均<0.01）;四组被试REM潜伏期、REM期持续时间、REM期占总睡眠时间比例差异均有统计学意义（F=41.492、11.827、10.552,P均<0.01）。睡眠呼吸相关指标方面,四组被试氧减指数差异有统计学意义（F=170.585,P<0.05）。结论 伴中重度OSAHS的抑郁症患者存在严重的睡眠进程和结构紊乱,同时伴有更频繁和更严重的呼吸相关事件。     

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.     

Subjective nocturnal symptoms have different associations with depressive symptoms and anxiety than with daytime sleepiness in patients with obstructive sleep apnea

BackgroundWe determined the relationships among the subjective symptoms of sleep apnea and daytime sleepiness, depressive symptoms, and anxiety in adults with obstructive sleep apnea (OSA).MethodsWe developed the Subjective Apnea Severity Questionnaire (SASQ) to measure subjective OSA symptoms during the night and on waking in the morning. Construct validity and reliability were assessed. The Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), and State Scale of State Trait Anxiety Inventory (STAI-S) were applied. Multiple linear regression analyses were performed, and the results were adjusted for several confounders.ResultsA total of 337 OSA patients were included. The SASQ consists of eight items with three domains. Cronbach's α for the SASQ was 0.657. The mean SASQ score was 1.35 ± 0.59. Symptoms related to nocturnal breathing difficulties were associated with polysomnographic (PSG) respiratory parameters. In the adjusted models, total SASQ scores were associated with ESS scores but not with BDI or STAI-S scores. Unlike other symptom groups, nocturnal breathing difficulties tended toward a positive relationship with ESS scores (p = 0.076), but were negatively related to BDI scores (p = 0.003) and STAI-S scores (p = 0.012). Symptoms related to nocturnal awakening or morning waking were either positively related or unrelated to ESS, BDI, and STAI-S scores.ConclusionsThe subjective OSA symptoms measured via the SASQ were associated with daytime sleepiness in adults with OSA, but not with depressive symptoms or anxiety. Nocturnal breathing difficulties were positively related to daytime sleepiness, but negatively related to depressive symptoms and anxiety.     

阻塞性呼吸睡眠暂停综合征与高血压并存患者脑血管功能状态的TCD初探

目的 研究分析阻塞性呼吸睡眠暂停综合征(OSAS)与高血压并存患者脑血管功能状态.方法 采用EME公司的COMPIONEⅡ型号经颅多普勒检查仪(TCD),对85例OSAS与高血压并存患者进行TCD检查,判断血管状态,采用屏气试验评价脑血管反应性,记录大脑中动脉(MCA)的平均血流速度(Vm)、搏动指数(PI),屏气指数(BHI)并与对照组比较,进行统计学分析.结果 两组间血管异常情况经χ~2检验,χ~2=4.1,P<0.05,差异有统计学意义.两组间的Vm经配对t检验,t=1.80,P>0.05差异无统计学意义.两组间的PI经配对t检验,t=1.62,P>0.05,差异无统计学意义.两组间BHI经配对t检验,t=4.75,P<0.01,差异有统计学意义.结论 OS-AS与高血压并存患者的脑血管功能状态与对照组比较脑血管反应性较差,更易发生动脉硬化,形成管腔狭窄.     

A multicenter evaluation of oral pressure therapy for the treatment of obstructive sleep apnea

ObjectiveWe aimed to evaluate the impact of a novel noninvasive oral pressure therapy (OPT) (Winx®, ApniCure) system on polysomnographic measures of sleep-disordered breathing, sleep architecture, and sleep stability in obstructive sleep apnea (OSA).Subjects and methodsA 4-week, multicenter, prospective, open-label, randomized, crossover, first-night order of control vs treatment, single-arm trial was conducted in five American Academy of Sleep Medicine (AASM) – accredited sleep clinics and one research laboratory. Sixty-three subjects (analysis cohort) were studied from a screening cohort of 367 subjects. The analysis cohort was 69.8% men, ages 53.6 ± 8.9 years (mean ± SD), body mass index of 32.3 ± 4.5 kg/m², with mild to severe OSA. At treatment initiation, subjects received random assignment to one night with and one without (control) treatment, and they were assessed again following 28 nights of treatment. Breathing and sleep architecture were assessed each night based on blind scoring by a single centralized scorer using AASM criteria.ResultsAverage nightly usage across the take-home period was 6.0 ± 1.4 h. There were no severe or serious device-related adverse events (AEs). Median apnea–hypopnea index (AHI) was 27.5 events per hour on the control night, 13.4 events per hour on the first treatment night, and 14.8 events per hour after 28 days of treatment. A clinically significant response (treatment AHI ⩽10/h and ⩽50% of control values) was seen in 20 of the 63 subjects evaluated. Rapid eye movement percentage (REM%) was significantly increased, and N1%, stage shifts to N1 sleep, overall stage shifts, total awakenings, and arousals per hour were all significantly reduced at both treatment nights compared to controls. Mean Epworth sleepiness scale (ESS) was significantly reduced from 12.1 to 8.6 (Cohen d effect size, 0.68) in those untreated for two or more weeks prior to OPT study participation and remained unchanged in subjects who directly switched from continuous positive airway pressure (CPAP) therapy to OPT.ConclusionClinically significant improvements in sleep quality and continuity, AHI, ODI, ESS, and overall clinical status were achieved in an easily identified subgroup. OPT was safe and well-tolerated and nightly usage was high.     

Hypercoagulability in patients with obstructive sleep apnea

BACKGROUND: Obstructive sleep apnea (OSA) has been linked to cardiovascular complications such as stroke and myocardial infarction. Previous studies demonstrate that OSA patients show elevated fibrinogen levels and increased platelet aggregation that are reversed with 1 night of nasal continuous positive airway pressure treatment (NCPAP). Questioning overall coagulability in OSA, we examined whole blood coagulability in 11 chronically NCPAP treated OSA subjects, 22 previously untreated OSA subjects, and in 16 of these after 1 night of NCPAP treatment. PATIENTS AND METHODS: During full polysomnography, subjects from each group had blood drawn prior to bedtime (21:00 h) and upon waking in the morning (07:00 h). RESULTS: Untreated OSA patients had faster P.M. clotting times than chronically treated OSA patients (3.33+/-0.31 versus 6.12+/- 0.66 min, P<0.05 by ANOVA). A.M. values showed similar results (4.31+/- 0.34 min versus 7.08+/-0.52 min, P<0.05 by ANOVA) for the respective groups. One overnight treatment with nasal CPAP did not produce a significant change in A.M. whole blood coagulability (4.35 +/-0.43 to 5.31+/-0.53 min; n=16; P=0.1) in 16 treated subjects. CONCLUSIONS: These data indicate a relationship between obstructive sleep apnea and blood hypercoagulability status that appears to be reversed by chronic NCPAP treatment. These data suggest that NCPAP might protect against the development of cardiovascular complications in OSA patients.     

Cerebrovascular reactivity in young and old patients with obstructive sleep apnea

ObjectiveImpaired cerebrovascular reactivity (CVR) in patients with obstructive sleep apnea syndrome (OSAS) increases the risk of ischemic stroke. CVR also decreases with age in normal individuals. However, it is unclear whether OSAS affects CVR differently in young and old patients. The aim of this study was to compare CVR in old and young patients with OSAS via transcranial Doppler (TCD) measurements of changes in cerebral blood flow velocity in the middle cerebral artery (MCAmv) during breath holding and hyperventilation.MethodsA total of 20 old patients (≥65 y) and 40 young patients (<65 y) with similar distributions of sex and OSAS severity were recruited for this study. The breath-holding index (BHI) and the hyperventilation index (HVI) were calculated to measure CVR.ResultsNo differences were found in MCAmv at baseline, apnea or hyperventilation between the two groups with different OSAS severities. However, reduced BHI (P < 0.01) and HVI (P < 0.01) were found in the young group with increasing severity of OSAS. Notably, the decline in BHI and HVI associated with OSAS severity was steeper in young patients than in old patients (P < 0.01).ConclusionsThese findings suggest that CVR in young patients is more impacted by OSAS severity than that in old patients, suggesting the existence of age-related cerebrovascular susceptibility to OSAS.