Renal function in patients with obstructive sleep apnea. Effects of nasal continuous positive airway pressure

Patients with obstructive sleep apnea (OSA) often exhibit nocturnal polyuria, which disappears with nasal continuous positive airway pressure (CPAP) treatment. We measured water and electrolyte urinary excretion, creatinine and osmolal clearances, and water transport during sleep in 13 polygraphically monitored patients with OSA during two consecutive nights, either untreated or treated with nasal CPAP, and in eight normal subjects. Untreated patients with OSA had greater urinary flows and greater urinary sodium, chloride, and potassium excretions than did controls. Nasal CPAP treatment in patients with OSA resulted in a reduction in urinary flow and in sodium and chloride excretion, with a concomitant increase in sodium resorption. None of these effects was observed in CPAP-treated normal subjects. The only effect of nasal CPAP common to normal subjects and patients was a trend toward decreased glomerular filtration rate.     

Long-term compliance with nasal continuous positive airway pressure therapy of obstructive sleep apnea

In an attempt to identify predictors of long-term compliance with nasal continuous positive airway pressure (CPAP), we reviewed the records of 125 patients with obstructive sleep apnea (OSA) referred to our center for nasal CPAP trials. Severity of sleep apnea, sleep staging, daytime hypersomnolence, effectiveness of nasal CPAP, previous palatal surgery, and adverse reactions were compared in compliant and noncompliant patients. Nineteen patients did not tolerate a nasal CPAP trial in the laboratory or refused home nasal CPAP therapy. Ten patients were unavailable for follow-up. Of the remaining 96 patients, 23 (24 percent) had discontinued therapy, while 73 (76 percent) were still using nasal CPAP at 14.5 +/- 10.7 months (mean +/- SD). There were no statistically significant differences between the compliant and noncompliant patients in baseline apnea plus hypopnea index (AHI), baseline sleep staging, AHI while receiving nasal CPAP, sleep staging while receiving nasal CPAP, or frequency of adverse reactions during therapy. Severe daytime sleepiness was present in 65 of the 73 compliant patients and in 12 of the 23 noncompliant patients (p less than 0.05). Ten of 43 in the compliant group had previous palatal surgery compared with ten of 23 noncompliant patients (p less than 0.05). Our data confirm earlier observations in smaller samples that compliant and noncompliant patients have equally severe sleep apnea and good initial responses to nasal CPAP. Long-term compliance with nasal CPAP may be associated with the severity of daytime hypersomnolence on presentation. Previous palatal surgery was more frequent in patients who did not tolerate long-term nasal CPAP therapy.     

The effect of continuous positive airway pressure on glucose control in diabetic patients with severe obstructive sleep apnea

Obstructive sleep apnea (OSA) is independently associated with glucose intolerance and insulin resistance, and recent studies have shown that continuous positive airway pressure (CPAP) improves insulin sensitivity. The objective of this study was to describe the change in glycosylated hemoglobin (HbA1c) after treatment with CPAP in patients with type 2 diabetes mellitus and OSA. To test this hypothesis, we performed a retrospective analysis of 38 patients seen in the sleep clinic of an urban public teaching hospital. All patients had OSA and type 2 diabetes mellitus, and their diabetic medication regimen had remained unchanged during the period of CPAP therapy. Sixty-one percent were men, body mass index was 42±9.5 kg/m², and the Apnea–Hypopnea Index was 53±36 per hour. HbA1c before therapy with CPAP was 7.8±1.4% and decreased to 7.3±1.3% after 134±119 days of therapy (p<0.001). Treatment with CPAP leads to a clinically significant drop in HbA1c in patients with type 2 diabetes mellitus and severe OSA.     

经鼻持续正压通气治疗夜间心绞痛合并阻塞性睡眠呼吸暂停低通气综合征

目的 探讨阻塞性睡眠呼吸暂停低通气综合征（OSAHS）和夜间心绞痛的关系以及经鼻持续正压通气治疗能否改善合并有OSAHS患者夜间心绞痛发作。方法 采用多导睡眠监测系统对46例夜间心绞痛患者进行整夜监测，对合并OSAHS的患者应用经鼻持续正压通气治疗，将患者治疗前后多导睡眠监测参数进行对照研究。结果 夜间心绞痛合并OSAHS的患者经持续正压通气治疗多导睡眠参数明显改善，治疗前后对比差异有显著性，心绞痛症状明显改善。结论 OSAHS和夜间心绞痛有相关性，OSAHS是夜间心绞痛发作的诱因。经鼻持续正压通气治疗可改善合并有0SAHS患者夜间心绞痛发作。     

Effect of nocturnal nasal continuous positive airway pressure on blood pressure in obstructive sleep apnea

Obstructive sleep apnea (OSA) is a very common risk factor for hypertension, and continuous positive airway pressure (CPAP) has been widely used to treat OSA. We conducted a meta-analysis of randomized, controlled trials to evaluate the effects of CPAP on blood pressure, reported as either a primary or secondary end point, among patients with OSA. Studies were retrieved by searching Medline (January 1980 to July 2006), the Cochrane Database of Systematic Reviews, conference abstracts, and bibliographies of review and original articles. From 255 relevant reports, 16 randomized clinical trials were selected that compared CPAP to control among participants with OSA, had a minimum treatment duration of 2 weeks, and reported blood pressure changes during the intervention or control period. Data on sample size, participant characteristics, study design, intervention methods, duration, and treatment results were independently abstracted by 2 investigators using a standardized protocol. Data from 16 trials representing 818 participants were examined using a random-effects model. Mean net change in systolic blood pressure for those treated with CPAP compared with control was -2.46 mm Hg (95% CI: -4.31 to -0.62); mean net change in diastolic blood pressure was -1.83 mm Hg (95% CI: -3.05 to -0.61); and mean net change in mean arterial pressure was -2.22 mm Hg (95% CI: -4.38 to -0.05). Net reductions in blood pressure were not statistically different between daytime and nighttime. These results indicate that CPAP decreases blood pressure among those with OSA and may help prevent hypertension.     

持续气道正压通气对阻塞性睡眠呼吸暂停患者睡眠结构的影响

目的探讨患者白天嗜睡等症状的原因,评估经鼻持续气道内正压通气(nCRAP)治疗对阻塞性睡眠呼吸暂停患者睡眠结构的影响。方法选择2001-2004年广东省佛山市第一人民医院呼吸科34例OSAS病人在睡眠多导生理记录仪监测下,进行nCPAP治疗,观察治疗前后呼吸紊乱指数、血氧饱和度和睡眠结构的变化。结果治疗后呼吸紊乱指数下降,最低血氧饱和度上升,睡眠结构明显改善。结论nCRAP能有效地改善OSAS病人的睡眠结构和呼吸紊乱。     

Effects of long-term nasal continuous positive airway pressure on C-reactive protein in patients with obstructive sleep apnea syndrome

Serum levels of C-reactive protein (CRP) were measured in 96 consecutive patients with obstructive sleep apnea syndrome (OSAS) before and after nasal continous positive airway pressure treatment. CRP levels only displayed significant correlations with body mass index (BMI) before treatment. No significant changes were observed in BMI and CRP levels after 9 months of treatment. These data suggest that CRP levels in patients with OSAS may be associated with obesity rather than OSAS itself.     

Effect of nasal continuous positive airway pressure in uncontrolled nocturnal asthmatic patients with obstructive sleep apnea syndrome

The mechanisms of nocturnal asthma are intimately related to circadian rhythms, which influence inflammatory cells and mediators, hormone levels and cholinergic tone. Nocturnal airway narrowing in asthma is sometimes associated with sleep disorders, such as obstructive sleep apnea syndrome (OSAS). The aims of this study were to evaluate the association of nocturnal asthma and OSAS, and investigate the influence of continuous positive airway pressure (CPAP) therapy to improve nighttime symptoms in asthmatic patients with OSAS. Forty-three asthmatic patients who had nocturnal symptoms in spite of the optimal medical treatment according to the Global Initiative for Asthma guidelines and associated with snoring were studied. Pulmonary function tests (PFTs), asthma nighttime symptom scores, and polysomnography were performed on all patients. We treated the patients with an apnea-hypopnea index (AHI) 15 (moderate-severe OSAS) (n=16) with CPAP during 2 months. After 2 months, PFT, asthma nighttime symptom scores were reperformed. There was no significant difference in PFT values before and after CPAP treatment in OSAS patients. Asthma nighttime symptom scores were improved significantly (P<0.05) after CPAP treatment. In conclusion, in some patients with nocturnal asthma, OSAS may be responsible disease for nocturnal symptoms. In this condition, CPAP improves nocturnal symptoms without amelioration in PFT abnormalities.     

Periodic leg movements in sleep following treatment of obstructive sleep apnea with nasal continuous positive airway pressure

Periodic leg movements in sleep are shown to be a common finding in patients with OSA and may become evident or increase in severity after treatment of the OSA with NCPAP. Periodic leg movements in sleep were measured during baseline polysomnography, a NCPAP treatment trial, and a repeat NCPAP recording in 33 patients treated with NCPAP for OSA. During baseline PSG, nine patients had five or more PLMS per hour of sleep (index), while 14 patients had a PLMSI of 5 or more during the NCPAP trial and the repeat NCPAP recording. Among those patients with a PLMSI of 5 or more during repeat NCPAP studies, the PLMSI showed a significant increase from baseline to initial NCPAP (16.9 +/- 25.3 vs 39.3 +/- 29.4; p less than 0.001) and from baseline to repeat NCPAP (16.9 +/- 25.3 vs 42.9 +/- 39.8; p less than 0.05). The number of PLMS associated with electroencephalographic arousal also increased significantly from baseline to initial NCPAP (4.3 +/- 7.4 vs 9.7 +/- 8.9; p less than 0.05) and from baseline to repeat NCPAP (4.3 +/- 7.4 vs 16.5 +/- 18.6; p less than 0.05). The 14 patients with a PLMSI of 5 or more on the repeat NCPAP had significantly more stage 1 sleep and less REM sleep than 19 patients with a PLMSI of less than 5. Bilateral anterior tibialis EMG must be measured during NCPAP recordings in order to recognize sleep disruption caused by PLMS.     

Neuropsychologic symptoms in obstructive sleep apnea improve after treatment with nasal continuous positive airway pressure

To describe the affective changes associated with sleep restoration we assessed psychologic symptoms using the Profile of Mood States questionnaire before and two months after treatment with nasal continuous positive airway pressure (NCPAP) in seven men with obstructive sleep apnea (OSA). The results were compared with those of a control group of patients with OSA who did not receive NCPAP. Two of six mood factors, depression and fatigue, improved significantly following treatment with NCPAP. Total Mood Disturbance (TMD) score was used to assess global mood differences. The mean TMD score for the patients before treatment was 1.7 and during treatment decreased to -7.6 (p less than 0.05). This mean decrease of 9.3 in the TMD score implies generalized improvement in mood. These findings support the opinion that sleep fragmentation and abnormalities of respiration during sleep are at least partially responsible for affective changes seen in sleep apnea. These psychologic disturbances improve after treatment with NCPAP.     

经鼻无创正压通气治疗阻塞性睡眠呼吸暂停综合征血栓前状态效果评价

目的评价经鼻无创正压通气(nCPAP)对阻塞性睡眠呼吸暂停综合征(OSAS)血栓前状态(PTS)的治疗效果。方法收集北京世纪坛医院2003年9月至2005年9月确诊的OSAS患者30例及同期健康对照者30名,血样采取均在经过前一夜睡眠监测及睡眠监测并nCPAP治疗后(OSAS组)仰卧位时立即进行。结果OSAS组与健康对照组比较,OSAS患者血液中血小板α颗粒膜蛋白-140(GMP-140)升高;部分凝血活酶时间(APTT)、抗凝血酶Ⅲ复合物(AT-Ⅲ)以及血浆组织型纤溶酶原激活物(t-PA)降低,血浆组织型纤溶酶原抑制物(PAI)升高,与健康对照组比较各个指标在两组之间的差异均有统计学意义。nCPAP治疗后OSAS组呼吸紊乱指数由(63.21±23.23)/h降至(0.56±0.84)/h,夜间最低血氧饱和度由0.68±0.07上升至0.90±0.02,GMP-140和PAI分别降至(17.07±7.97)%、(95.83±5.91)%,AT-Ⅲ和t-PA分别升高至(95.20±6.67)%、(5.45±1.61)μg/L。结论OSAS患者存在PTS,nCPAP治疗可部分或全部逆转PTS,减少与OSAS相关的心脑血管栓塞性疾病的发生。     

Impact of nasal continuous positive airway pressure therapy on markers of platelet activation in patients with obstructive sleep apnea

BACKGROUND: Considerable evidence implicates CD40 signaling in the pathogenesis of atheromas. Exposure to CD40 ligand induces platelet-leukocyte conjugation, a heightened expression of inflammatory cytokines, matrix-degrading enzymes, and procoagulant factors. OBJECTIVES: To investigate the association between plasma soluble CD40 ligand (sCD40L) and platelet-monocyte aggregates in patients with obstructive sleep apnea (OSA) and to determine whether treatment of OSA with nasal continuous positive airway pressure (nCPAP) alters this relationship. METHODS: Twelve patients with OSA who were free of other diseases and 12 healthy controls matched for age, gender, and body mass index had blood drawn for sCD40L and platelet-monocyte aggregate measurements. A repeat assessment was obtained following 8 weeks of nCPAP therapy. RESULTS: Subjects with OSA had significantly higher plasma sCD40L levels and exhibited elevated platelet-monocyte aggregates compared to nonapneic subjects (7.6 +/- 4.3 versus 1.7 +/- 1.1, p = 0.004; and 41.3 +/- 23.7 versus 6.7 +/- 4.9, p = 0.001, respectively). Both parameters correlated positively with the percentage of time spent with SpO(2) <90% (r = 0.69, p = 0.01 and r = 0.6, p = 0.03, respectively). After 8 weeks of nCPAP treatment, sCD40 levels declined by 47% (p = 0.003) and platelet-monocyte aggregates by 42% (p = 0.002). None of the controls showed any changes in either sCD40L or platelet- monocyte aggregates after nCPAP therapy. CONCLUSIONS: OSA is associated with upregulation of circulating sCD40L levels and platelet-monocyte aggregation that may account for the increased incidence of cardiovascular events in this population. Treatment with nCPAP may alleviate this risk.     

Effects of nasal continuous positive airway pressure on soluble cell adhesion molecules in patients with obstructive sleep apnea syndrome

PURPOSE: Obstructive sleep apnea syndrome is common in middle-aged men and may be associated with an increased risk of cardiovascular disease. We investigated the effect of nasal continuous positive airway pressure (CPAP) treatment on levels of soluble cell adhesion molecules-which have been shown to be associated with the development of atherosclerosis-in these patients. SUBJECTS AND METHODS: We studied 23 patients with obstructive sleep apnea syndrome diagnosed by polysomnography who were treated with nasal CPAP. Serum soluble intercellular adhesion molecule-1, E-selectin, and vascular cell adhesion molecule-1 levels were measured before nasal CPAP was started, and after 3 or 4 days (n = 19), 1 month (n = 23), or 6 months (n = 11) of treatment. RESULTS: After 3 to 4 days of nasal CPAP therapy, the mean (+/- SD) soluble E-selectin level had decreased from 89 +/- 44 ng/mL to 69 +/- 28 ng/mL (P = 0.002). After 1 month, the soluble intercellular adhesion molecule-1 level had decreased from 311 +/- 116 ng/mL to 249 +/- 74 ng/mL (P = 0.02). After 6 months, soluble vascular cell adhesion molecule-1 levels had not changed significantly, while the mean soluble intercellular adhesion molecule-1 level (212 +/- 59 ng/mL) had decreased further (P = 0.02). Before treatment, soluble intercellular adhesion molecule-1 levels and the apnea and hypopnea index were correlated (r = 0.43, P = 0.04). CONCLUSIONS: Obstructive sleep apnea and hypopnea have a significant adverse effect on serum soluble cell adhesion molecule-1 levels that may be reduced by nasal CPAP treatment.     

Profiles of 939 patients with obstructive sleep apnea syndrome treated with continuous positive pressure

The aim of this study was to analyze the characteristics of patients on long-term continuous positive pressure therapy for obstructive sleep apnea in order to determine the efficacy, observance, tolerance, degree of patient satisfaction and patient quality of life using the Nottingham scale. A questionnaire was sent to 939 patients treated for at least six months in 11 centers. Factorial analysis of multiple correspondences and two classification analyses were used to establish patient profiles. Factorial analysis evidenced a relationship between patient satisfaction, reduced symptoms, observance and tolerance. The classification analyses distinguished three groups. Group A (n = 596) included primarily men (93%) who were satisfied with the treatment (99%) and showed good observance. Group B (n = 284) was characterized by patient satisfaction, observance, improved symptoms and lower quality of life than group A. Group C was composed of older patients who were satisfied with their treatment and showed good observance but who had no notable improvement in their symptoms. In conclusion, this study pointed out the difficulty in defining which patients with obstructive sleep apnea would benefit most from continuous positive pressure therapy. Good observance is not a sufficient criterion for therapeutic efficacy.     

Efficacy of continuous positive airway pressure on arrhythmias in obstructive sleep apnea patients

The purpose of this study was to determine the relationship between obstructive sleep apnea (OSA) and cardiovascular disorders in a large Japanese population, and to assess the efficacy of continuous positive airway pressure (CPAP) in the treatment of OSA-associated arrhythmias. The study population comprised 1394 Japanese subjects (1086 men and 308 women) who were divided into four groups on the basis of polysomnography (PSG) analysis as follows: the no sleep apnea (N-SA) group (n = 44, apnea-hypopnea index [AHI] < 5), the mild OSA (Mi-OSA) group (n = 197, 5 < AHI < 15), the moderate OSA (Mo) group (n = 368, 15 < AHI < 30), and severe OSA (SOSA) group (n = 785, AHI < 30). The following baseline characteristics were significantly associated with OSA: age (P < 0.001), gender (P < 0.001), body mass index (P < 0.001), hypertension (P < 0.001), diabetes (P = 0.009), and hyperlipidemia (P = 0.013). In the OSA group, PSG revealed the predominance of paroxysmal atrial fibrillation (PAF) (P = 0.051), premature atrial complex short run (P < 0.005), premature ventricular complex (PVC, P = 0.004), sinus bradycardia (P = 0.036), and sinus pause (arrest >2 s, P < 0.001) during the PSG recording. A total of 316 patients from the group underwent CPAP titration and were then re-evaluated. Continuous positive airway pressure therapy significantly reduced the occurrences of PAF (P < 0.001), PVC (P = 0.016), sinus bradycardia (P = 0.001), and sinus pause (P = 0.004). The results of this study demonstrate a significant relationship between OSA and several cardiac disorders, and also demonstrate the efficacy of CPAP in preventing OSA-associated arrhythmias in a large population of Japanese patients.     

经鼻持续气道正压通气治疗睡眠呼吸暂停综合征的依从性及其影响因素

目的　调查睡眠呼吸暂停综合征 (SAS)患者接受经鼻持续气道正压通气 (nCPAP)治疗的依从性、主观疗效和不良反应 ,了解影响依从性的相关因素。方法　对我院 1994年 2月～ 2 0 0 0年 8月间接受nCPAP治疗的 118例SAS患者进行有关依从性的问卷调查并分析其影响因素。结果　 118例SAS患者中 5 7%应用nCPAP依从性良好 ,影响nCPAP治疗依从性的因素主要有治疗前睡眠呼吸暂停 /低通气指数 (AHI) (P =0 0 35 )、治疗前夜间最低血氧饱和度 (LSaO2 ) (P =0 0 0 6 )、治疗前及后Epworth嗜睡评分 (ESS) (P值均 <0 0 0 1)及CPAP呼吸机的性能 (P <0 0 0 1)。结论　 5 7%的SAS患者能长期坚持应用nCPAP治疗 ,nCPAP可作为SAS长期治疗的重要手段 ;影响nCPAP治疗依从性的因素主要有治疗前AHI、治疗前夜间LSaO2 、治疗前及后ESS及CPAP呼吸机的性能。