Tracheostomy Tube Failure in Obstructive Sleep Apnea

In our institutions we routinely do posttracheostomy sleep studies on patients being treated for obstructive sleep apnea. We have identified several patients who failed to show objective evidence of improvement after tracheostomy. From our studies we have found that both mechanical obstruction and concomitant respiratory control dysfunction caused this failure. A unique tracheostomy tube was constructed to treat the subset of patients with internal collapse of the tracheostomy tube.     

Brain Structure Network Analysis in Patients with Obstructive Sleep Apnea

Childhood obstructive sleep apnea (OSA) is a sleeping disorder commonly affecting school-aged children and is characterized by repeated episodes of blockage of the upper airway during sleep. In this study, we performed a graph theoretical analysis on the brain morphometric correlation network in 25 OSA patients (OSA group; 5 female; mean age, 10.1 ± 1.8 years) and investigated the topological alterations in global and regional properties compared with 20 healthy control individuals (CON group; 6 females; mean age, 10.4 ± 1.8 years). A structural correlation network based on regional gray matter volume was constructed respectively for each group. Our results revealed a significantly decreased mean local efficiency in the OSA group over the density range of 0.32–0.44 (p < 0.05). Regionally, the OSAs showed a tendency of decreased betweenness centrality in the left angular gyrus, and a tendency of decreased degree in the right lingual and inferior frontal (orbital part) gyrus (p < 0.005, uncorrected). We also found that the network hubs in OSA and controls were distributed differently. To the best of our knowledge, this is the first study that characterizes the brain structure network in OSA patients and invests the alteration of topological properties of gray matter volume structural network. This study may help to provide new evidence for understanding the neuropathophysiology of OSA from a topological perspective.     

The Consolidation of Implicit Sequence Memory in Obstructive Sleep Apnea

Obstructive Sleep Apnea (OSA) Syndrome is a relatively frequent sleep disorder characterized by disrupted sleep patterns. It is a well-established fact that sleep has beneficial effect on memory consolidation by enhancing neural plasticity. Implicit sequence learning is a prominent component of skill learning. However, the formation and consolidation of this fundamental learning mechanism remains poorly understood in OSA. In the present study we examined the consolidation of different aspects of implicit sequence learning in patients with OSA. We used the Alternating Serial Reaction Time task to measure general skill learning and sequence-specific learning. There were two sessions: a learning phase and a testing phase, separated by a 10-hour offline period with sleep. Our data showed differences in offline changes of general skill learning between the OSA and control group. The control group demonstrated offline improvement from evening to morning, while the OSA group did not. In contrast, we did not observe differences between the groups in offline changes in sequence-specific learning. Our findings suggest that disrupted sleep in OSA differently affects neural circuits involved in the consolidation of sequence learning.     

Heart Rate Responses to Autonomic Challenges in Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is accompanied by structural alterations and dysfunction in central autonomic regulatory regions, which may impair dynamic and static cardiovascular regulation, and contribute to other syndrome pathologies. Characterizing cardiovascular responses to autonomic challenges may provide insights into central nervous system impairments, including contributions by sex, since structural alterations are enhanced in OSA females over males. The objective was to assess heart rate responses in OSA versus healthy control subjects to autonomic challenges, and, separately, characterize female and male patterns. We studied 94 subjects, including 37 newly-diagnosed, untreated OSA patients (6 female, age mean±std: 52.1±8.1 years; 31 male aged 54.3±8.4 years), and 57 healthy control subjects (20 female, 50.5±8.1 years; 37 male, 45.6±9.2 years). We measured instantaneous heart rate with pulse oximetry during cold pressor, hand grip, and Valsalva maneuver challenges. All challenges elicited significant heart rate differences between OSA and control groups during and after challenges (repeated measures ANOVA, p<0.05). In post-hoc analyses, OSA females showed greater impairments than OSA males, which included: for cold pressor, lower initial increase (OSA vs. control: 9.5 vs. 7.3 bpm in females, 7.6 vs. 3.7 bpm in males), OSA delay to initial peak (2.5 s females/0.9 s males), slower mid-challenge rate-of-increase (OSA vs. control: −0.11 vs. 0.09 bpm/s in females, 0.03 vs. 0.06 bpm/s in males); for hand grip, lower initial peak (OSA vs. control: 2.6 vs. 4.6 bpm in females, 5.3 vs. 6.0 bpm in males); for Valsalva maneuver, lower Valsalva ratio (OSA vs. control: 1.14 vs. 1.30 in females, 1.29 vs. 1.34 in males), and OSA delay during phase II (0.68 s females/1.31 s males). Heart rate responses showed lower amplitude, delayed onset, and slower rate changes in OSA patients over healthy controls, and impairments may be more pronounced in females. The dysfunctions may reflect central injury in the syndrome, and suggest autonomic deficiencies that may contribute to further tissue and functional pathologies.     

Obstructive Sleep Apnea in Extremely Overweight Adolescents undergoing Bariatric Surgery

Objectives: To determine the prevalence of obstructive sleep apnea (OSA) in extremely overweight adolescents and to examine the effect of significant weight loss on OSA severity. Research Methods and Procedures: We reviewed the anthropometric and polysomnographic data on all extremely overweight adolescents who underwent laparoscopic Roux en Y gastric bypass surgery at Cincinnati Children's Hospital Medical Center from July 2001 to September 2004. Repeat polysomnograms were performed after significant weight loss. Comparisons were made between pre‐ and postoperative polysomnographic data. Results: Nineteen of 34 patients (55%) who underwent bariatric surgery were diagnosed with OSA. Subsequent to surgery, 10 of these patients returned for follow‐up polysomnographic testing. After significant weight loss (mean, 58 kg), OSA severity markedly decreased in all patients (median apnea‐hypopnea index at baseline vs. after weight loss, 9.1 vs. 0.65). Discussion: Our study indicated that OSA was highly prevalent in extremely overweight adolescents meeting eligibility criteria for bariatric surgery. The significant weight loss after gastric bypass was associated with a marked reduction in OSA severity.     

经鼻高流量氧疗对阻塞性睡眠呼吸暂停综合征患者的临床疗效研究

目的:探讨经鼻高流量氧疗对阻塞性睡眠呼吸暂停综合征患者的临床疗效。方法:选择2013年7月至2017年7月我院接诊的80例急阻塞性睡眠呼吸暂停综合征患者进行研究,通过随机数表法分为观察组(n=45)和对照组(n=35)。观察组采用经鼻高流量氧疗进行治疗,对照组采用无创正压通气进行治疗,比较两组临床疗效、夜间呼吸暂停时间、呼吸暂停低通气指数(AHI)、总睡眠时间、醒觉时间、血氧饱和度、治疗前后血压、高敏C反应蛋白(hs-CRP)、低密度脂蛋白(LDL)、总胆固醇(TC)水平及生活质量评分的变化。结果:观察组患者治疗后有效率为88.89%,显著高于对照组(71.43%,P0.05)。治疗后,观察组夜间最低血氧饱和度、总睡眠时间、醒觉时间、生活质量评分均明显高于对照组,AHI、收缩压、舒张压、平均动脉压、血清hs-CRP、LDL以及TC水平均显著低于对照组(P0.05)。结论:经鼻高流量氧疗用于阻塞性睡眠呼吸暂停综合征患者的临床疗效明显优于无创正压通气进行治疗,其可显著改善患者的临床症状,提高患者的生活质量。     

儿童与成人阻塞型睡眠呼吸暂停低通气综合征代谢异常特征的比较

目的：探讨儿童及成人阻塞型睡眠呼吸暂停低通气综合症（OSAHS）发病原因、睡眠呼吸紊乱严重程度及合并代谢异常程度的差别。方法：对我院2003年1月1日至20]0年7月1日71例诊断为OSAHS住院患者进行回顾性调查,登记年龄、性男日、发病原因、血压、白细胞计数、中性粒细胞比率、淋巴细胞比率、呼吸暂停低通气指数（AHI）、夜间最低血氧饱和度、微觉醒指数。根据年龄进行分组,年龄〈18岁者为A组,年龄≥18岁者为B组。比较两组发病原因、睡眠呼吸紊乱及合并代谢异常程度的差剐。结果：1．A组慢性扁桃体炎和（或）腺样体肥大发生率明显高于B组（P〈O．01）,鼻中隔偏曲发生率明显低于B组（P〈0．01）。2．与B组比较,A组AHI及微觉醒指数降低,夜间最低血氧饱和度升高（P〈0．01）;3．与B组比较,A组高血压、中性粒细胞比率、谷丙转氨酶比例降低（P〈0．05）。结论：A组睡眠呼吸紊乱程度及代谢异常较B组程度轻,更需关注成人阻塞型睡眠呼吸暂停低通气综合症的综合治疗。     

儿童与成人阻塞型睡眠呼吸暂停低通气综合征代谢 异常特征的比较

目的:探讨儿童及成人阻塞型睡眠呼吸暂停低通气综合症(OSAHS)发病原因、睡眠呼吸紊乱严重程度及合并代谢异常程度的差别。方法:对我院2003年1月1日至2010年7月1日71例诊断为OSAHS住院患者进行回顾性调查,登记年龄、性别、发病原因、血压、白细胞计数、中性粒细胞比率、淋巴细胞比率、呼吸暂停低通气指数(AHI)、夜间最低血氧饱和度、微觉醒指数。根据年龄进行分组,年龄<18岁者为A组,年龄≥18岁者为B组。比较两组发病原因、睡眠呼吸紊乱及合并代谢异常程度的差别。结果:1.A组慢性扁桃体炎和(或)腺样体肥大发生率明显高于B组(P<0.01),鼻中隔偏曲发生率明显低于B组(P<0.01)。2.与B组比较,A组AHI及微觉醒指数降低,夜间最低血氧饱和度升高(P<0.01);3.与B组比较,A组高血压、中性粒细胞比率、谷丙转氨酶比例降低(P<0.05)。结论:A组睡眠呼吸紊乱程度及代谢异常较B组程度轻,更需关注成人阻塞型睡眠呼吸暂停低通气综合症的综合治疗。     

T Regulatory Lymphocytes and Endothelial Function in Pediatric Obstructive Sleep Apnea

Background

Obstructive sleep apnea (OSA) is a low-grade inflammatory disease affecting the cardiovascular and metabolic systems. Increasing OSA severity reduces T-regulatory lymphocytes (Tregs) in OSA children. Since Tregs modulate endothelial activation, and attenuate insulin resistance, we hypothesized that Tregs are associated with endothelial and metabolic dysfunction in pediatric OSA.

Methods

50 consecutively recruited children (ages 4.8–12 years) underwent overnight polysomnography and fasting homeostatic model (HOMA) of insulin resistance was assessed. Percentage of Tregs using flow cytometry, and endothelial function, expressed as the time to peak occlusive hyperemia (Tmax), were examined. In a subgroup of children (n = 21), in vitro Treg suppression tests were performed.

Results

Circulating Tregs were not significantly associated with either BMI z score or HOMA. However, a significant inverse correlation between percentage of Tregs and Tmax emerged (p<0.0001, r = −0.56). A significant negative correlation between Tregs suppression and the sleep pressure score (SPS), a surrogate measure of sleep fragmentation emerged (p = 0.02, r = −0.51) emerged, but was not present with AHI.

Conclusions

Endothelial function, but not insulin resistance, in OSA children is strongly associated with circulating Tregs and their suppressive function, and appears to correlate with sleep fragmentation. Thus, alterations in T cell lymphocytes may contribute to cardiovascular morbidity in pediatric OSA.     

Focus: Health Equity: Gender Issues in Obstructive Sleep Apnea

Obstructive sleep apnea has historically been considered a male disease. Although most studies have shown male predominance, obstructive sleep apnea is highly prevalent in women, increasing with age and varying with physiologic status among other factors. Obstructive sleep apnea is associated with significant symptoms and health consequences in women yet remains underdiagnosed in women in part due to differences in presenting symptoms, differences in polysomnographic findings, and/or sociocultural factors. This review will discuss the epidemiology, pathophysiology, clinical presentation, diagnostic findings, and treatment of obstructive sleep apnea, focusing on sex and gender differences.     

Vascular Dysfunction in Obstructive Sleep Apnea and Type 2 Diabetes Mellitus

Despite the high prevalence of obstructive sleep apnea (OSA) in type 2 diabetes mellitus (DM), the attributable vascular risk from each condition is unknown. We hypothesize that OSA may have a similar effect on vascular function as type 2 diabetes does. Healthy normal‐weight subjects, healthy obese subjects, subjects with type 2 diabetes, and obese subjects with OSA were enrolled. Vascular function was assessed with brachial artery ultrasound for flow‐mediated dilatation (FMD) and in skin microcirculation by laser Doppler flowmetry. One hundred fifty‐three subjects were studied: healthy normal‐weight controls (NCs) (n = 14), healthy obese controls (OCs) (n = 33), subjects with DM (n = 68), and obese subjects with OSA (n = 38). The DM group did not undergo sleep study and thus may have had subclinical OSA. The OSA and type 2 diabetes groups had impaired FMD as compared to both the normal‐weight and OC groups (5.8 ± 3.8%, 5.4 ± 1.6% vs. 9.1 ± 2.5%, 8.3 ± 5.1%, respectively, P < 0.001, post hoc Fischer test). When referenced to the NC group, a multiple linear regression model adjusting for covariates found that baseline brachial artery diameter (β = ?3.75, P < 0.001), OSA (β = ?2.45, P = 0.02) and type 2 diabetes status (β = ?2.31, P = 0.02), negatively predicted % FMD. OSA status did not seem to affect nitroglycerin‐induced vasodilation (endothelium‐independent) of the brachial artery or vascular function in the skin microcirculation. OSA impairs endothelial function in the brachial artery to a similar degree as type 2 diabetes does. OSA, however, does not appear to affect brachial endothelium‐independent vasodilation or skin microcirculatory function. Treatment of OSA in patients with concomitant type 2 diabetes, therefore, may be a potential therapeutic option to improve macro‐, but not microvascular outcomes.     

儿童阻塞性睡眠呼吸暂停低通气综合征与肥胖的相关性研究

目的:探讨儿童阻塞性睡眠呼吸暂停/低通气综合征(OSAHS)与肥胖的相关性。方法:收集单纯性肥胖儿童120例和体重正常儿童110例作为研究对象,进行统一的体格检查和专科检查,并进行多导睡眠监测记录阻塞性呼吸暂停指数(OAI)、呼吸暂停/低通气指数(AHI)、中枢性呼吸暂停指数(CAI)、最低血氧饱和度(LSa O2)和睡眠效率。结果:肥胖组OSAHS患病率为58.33%显著高于对照组的31.82%,差异有统计学意义(P0.05);OAI、AHI、CAI均显著高于对照组,而LSa O2、睡眠效率指标显著低于对照组,差异均有统计学意义(均P0.05);多因素回归分析显示,肥胖、扁桃体增生、腺样体增生是导致OSAHS的独立危险因素,差异有统计学意义(均P0.05)。结论:肥胖是儿童OSAHS发病的重要影响因素,特别是合并扁桃体肿大或腺样体肿大的患儿应注意预防OSAHS的发生。     

Global Brain Blood-Oxygen Level Responses to Autonomic Challenges in Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is accompanied by brain injury, perhaps resulting from apnea-related hypoxia or periods of impaired cerebral perfusion. Perfusion changes can be determined indirectly by evaluation of cerebral blood volume and oxygenation alterations, which can be measured rapidly and non-invasively with the global blood oxygen level dependent (BOLD) signal, a magnetic resonance imaging procedure. We assessed acute BOLD responses in OSA subjects to pressor challenges that elicit cerebral blood flow changes, using a two-group comparative design with healthy subjects as a reference. We separately assessed female and male patterns, since OSA characteristics and brain injury differ between sexes. We studied 94 subjects, 37 with newly-diagnosed, untreated OSA (6 female (age mean ± std: 52.1±8.1 yrs; apnea/hypopnea index [AHI]: 27.7±15.6 events/hr and 31 male 54.3±8.4 yrs; AHI: 37.4±19.6 events/hr), and 20 female (age 50.5±8.1 yrs) and 37 male (age 45.6±9.2 yrs) healthy control subjects. We measured brain BOLD responses every 2 s while subjects underwent cold pressor, hand grip, and Valsalva maneuver challenges. The global BOLD signal rapidly changed after the first 2 s of each challenge, and differed in magnitude between groups to two challenges (cold pressor, hand grip), but not to the Valsalva maneuver (repeated measures ANOVA, p<0.05). OSA females showed greater differences from males in response magnitude and pattern, relative to healthy counterparts. Cold pressor BOLD signal increases (mean ± adjusted standard error) at the 8 s peak were: OSA 0.14±0.08% vs. Control 0.31±0.06%, and hand grip at 6 s were: OSA 0.08±0.03% vs. Control at 0.30±0.02%. These findings, indicative of reduced cerebral blood flow changes to autonomic challenges in OSA, complement earlier reports of altered resting blood flow and reduced cerebral artery responsiveness. Females are more affected than males, an outcome which may contribute to the sex-specific brain injury in the syndrome.     

Glucose Tolerance and Weight Loss in Obese Women with Obstructive Sleep Apnea

Background

The association of obstructive sleep apnea (OSA) with glucose intolerance and the beneficial effect of lifestyle intervention have been poorly investigated in women particularly before menopausal status. The study explored 1) whether OSA is associated with impaired glucose homeostasis in obese non diabetic premenopausal and menopausal women and 2) the effects of a 3- month lifestyle intervention on glucose homeostasis in OSA women.

Design and Methods

We consecutively recruited 98 obese women (39 premenopausal) from those referred for a weight loss intervention. Ambulatory nocturnal polysomnography, body composition, oral glucose tolerance test, insulin sensitivity and β cell function were assessed before and after intervention.

Results

41% of premenopausal and 64% of menopausal women had OSA which was associated with worse glucose homeostasis before menopausal status. Mean and minimal nocturnal oxygen saturation (SaO₂) was associated with neck/height ratio (NHR), independently of total and central obesity. Mean and minimal nocturnal SaO₂ and NHR were correlated with insulin sensitivity and fasting glucose. In multivariate analyses, nocturnal mean SaO₂ was negatively and independently correlated with fasting glucose (p<0.0001) and NHR with insulin sensitivity (p<0.0001). In OSA women, the intervention induced a 5% weight reduction and a significant increase in minimal nocturnal SaO₂, insulin sensitivity and β cell function. Changes in fasting glucose and insulin sensitivity were associated with those in minimal nocturnal SaO₂ (p<0.05) and not with weight loss.

Conclusions

In obese women, glucose homeostasis worsens due to nocturnal hypoxia and increased neck circumference through mechanisms partially independent of obesity. OSA is more clearly associated with glucose intolerance in premenopausal than in menopausal women. In OSA women, the improvement of nocturnal hypoxia induced by lifestyle modifications is associated with that of glucose homeostasis.     

Relationship between Obstructive Sleep Apnea Severity and Sleep,Depression and Anxiety Symptoms in Newly-Diagnosed Patients

Obstructive sleep apnea (OSA) occurs in at least 10% of the population, and leads to higher morbidity and mortality; however, relationships between OSA severity and sleep or psychological symptoms are unclear. Existing studies include samples with wide-ranging comorbidities, so we assessed relationships between severity of OSA and common sleep and psychological disturbances in recently diagnosed OSA patients with minimal co-morbidities. We studied 49 newly diagnosed, untreated OSA patients without major co-morbidities such as mental illness, cardiovascular disease, or stroke; subjects were not using psychoactive medications or tobacco (mean ± std age: 46.8±9.1 years; apnea/hyponea index [AHI]: 32.1±20.5 events/hour; female/male: 12/37; weight <125 kg). We evaluated relationships between the AHI and daytime sleepiness (Epworth Sleepiness Scale; ESS), sleep quality (Pittsburg Sleep Quality Index; PSQI), depressive symptoms (Beck Depression Inventory-II; BDI), and anxiety symptoms (Beck Anxiety Inventory; BAI), as well as sex and body mass index (BMI). AHI was similar in females and males. Mean levels of all symptoms were above normal thresholds, but AHI was not correlated with age, ESS, PSQI, BDI, or BAI; only BMI was correlated with OSA severity. No differences in mean AHI appeared when subjects were grouped by normal versus elevated values of ESS, PSQI, BDI, or BAI. Consistent with other studies, a strong link between OSA severity and psychological symptoms did not appear in these newly diagnosed patients, suggesting that mechanisms additional to the number and frequency of hypoxic events and arousals occurring with apneas contribute to adverse health effects in OSA. OSA patients presenting with mild or moderate severity, and no major co-morbidities will not necessarily have low levels of sleep or psychological disturbances.     

Impact of Acetazolamide and CPAP on Cortical Activity in Obstructive Sleep Apnea Patients

Study Objectives

1) To investigate the impact of acetazolamide, a drug commonly prescribed for altitude sickness, on cortical oscillations in patients with obstructive sleep apnea syndrome (OSAS). 2) To examine alterations in the sleep EEG after short-term discontinuation of continuous positive airway pressure (CPAP) therapy.

Design

Data from two double-blind, placebo-controlled randomized cross-over design studies were analyzed.

Setting

Polysomnographic recordings in sleep laboratory at 490 m and at moderate altitudes in the Swiss Alps: 1630 or 1860 m and 2590 m.

Patients

Study 1: 39 OSAS patients. Study 2: 41 OSAS patients.

Interventions

Study 1: OSAS patients withdrawn from treatment with CPAP. Study 2: OSAS patients treated with autoCPAP. Treatment with acetazolamide (500–750 mg) or placebo at moderate altitudes.

Measurements and Results

An evening dose of 500 mg acetazolamide reduced slow-wave activity (SWA; approximately 10%) and increased spindle activity (approximately 10%) during non-REM sleep. In addition, alpha activity during wake after lights out was increased. An evening dose of 250 mg did not affect these cortical oscillations. Discontinuation of CPAP therapy revealed a reduction in SWA (5–10%) and increase in beta activity (approximately 25%).

Conclusions

The higher evening dose of 500 mg acetazolamide showed the “spectral fingerprint” of Benzodiazepines, while 250 mg acetazolamide had no impact on cortical oscillations. However, both doses had beneficial effects on oxygen saturation and sleep quality.     

Distinct Associations between Hypertension and Obstructive Sleep Apnea in Male and Female Patients

Obstructive sleep apnea (OSA) is highly associated with hypertension. However, the correlation between hypertension and OSA at different levels of severity and the influence of gender on that correlation are unclear. A total of 996 patients (776 males and 190 females) with OSA were recruited. The influence of gender on the correlation between hypertension and OSA at different stratifications of severity, based on the apnea-hypopnea index (AHI), was fully evaluated together with the major health risk factors obesity, age, and diabetes. Females with OSA were significantly older on average than males with OSA. Moreover, females had milder degrees of OSA on average than the extent of severity seen in males. The proportion of females with diabetes or hypertension was higher than that of males. The proportion of males with hypertension and obesity increased significantly with OSA, and age also increased with OSA. The percentage of females with hypertension at different degrees of OSA severity was stable at about 26% in the mild, moderate, and severe OSA groups. Among females, age was increased significantly in the moderate relative to the mild OSA group. Moreover, the proportion of obese subjects was increased significantly in the severe compared with the moderate OSA group. The proportions of males and females with diabetes were not significantly different among all OSA severity groups. An ordinal multivariate logistic regression analysis confirmed that hypertension, age, and obesity were associated with OSA severity in males, whereas only age and obesity were associated with OSA severity in females. Although the proportion of subjects with hypertension was higher in females with OSA than in males with OSA, the proportion of subjects with hypertension increased as the severity of OSA increased in males but not in females.     

心理干预对阻塞性睡眠呼吸暂停综合征患者的意义

目的:评价在常规手术治疗的基础上联用心理干预措施治疗OSAS的效果.方法:50例OSAS患者随机分为对照组和观察组,对照组采用常规手术治疗,观察组在此基础上,联用心理干预措施.对两组患者的焦虑自评量表(SAS)、抑郁自评量表(SDS)、李克特量问卷调查表评分进行比较.结果:治疗前两组SAS、SDS评分差异不显著,有可比性.治疗后观察组SAS评分为(35.15±6.12)分,明显低于对照组(44.28±7.39)分,具有显著差异(t=4.7576,P＜0.001,见表1);治疗后观察组SDS评分为(37.59±6.34)分,明显低于对照组(42.75±5.69)分,具有显著差异(t=3.0286,P＜0.01,见表1).观察组总满意率为76.00%明显高于对照组的总满意率40.00%,差异显著,具有统计学意义(χ2=6.6502,P＜0.01,见表2).结论:在采用常规手术治疗的基础上联用了心理干预措施治疗OSAS的方式有明显效果,建议临床上进一步推广.