Afternoon serum-melatonin in sleep disordered breathing

OBJECTIVES: To study afternoon serum-melatonin values in patients with sleep disordered breathing. Melatonin has a strong circadian rhythm with high values during the night-time and low values in the afternoon. Sleep disordered breathing may change the circadian rhythm of melatonin which may have diagnostic implications. SETTING: The Sleep Laboratory, The Department of Internal Medicine, Avesta Hospital, Sweden, and the Department of Anaesthesiology, Glostrup University Hospital, Copenhagen, Denmark. SUBJECTS: We examined 60 consecutive patients admitted for sleep disordered breathing and 10 healthy non snoring controls. The patients underwent a sleep apnoea screening test having a specificity of 100% for the obstructive sleep apnoea syndrome (OSAS) using a combination of static charge sensitive bed and oximetry. Obstructive sleep apnoea syndrome was found in 49 patients, eight patients had borderline sleep disordered breathing (BSDB) and three patients were excluded due to interfering disease. MAIN OUTCOME MEASURES: Patients and controls had an afternoon determination of serum-melatonin. The Epworth Sleepiness Scale was used to score day-time sleepiness. RESULTS: In comparison with normal controls patients suffering from OSAS had significantly higher serum-melatonin levels in the afternoon. However, as a diagnostic test for OSAS in patients with sleep disordered breathing serum-melatonin showed a low sensitivity but a high specificity. The results indicate that breathing disorders during sleep in general affect pineal function. CONCLUSIONS: Sleep disordered breathing seems to disturb pineal function. Determination of afternoon serum-melatonin alone or together with a scoring of daytime sleepiness does not identify OSAS-patients in a heterogeneous population of patients complaining of heavy snoring and excessive daytime sleepiness.     

Sleep disordered breathing: management update

The term sleep disordered breathing encompasses a spectrum of abnormalities, including snoring, obstructive sleep apnoea (OSA), central sleep apnoea (CSA), respiratory‐related arousals and hypoventilation. This review focuses on both OSA and CSA. It provides a clinical update of recent advances in the diagnosis, management and prognosis of these two conditions. An increasing array of treatment modalities, particularly for OSA, broadens the opportunity for personalised therapy tailored to the individual patient.     

Prevalence of sleep apnoea in diabetic patients

Background: Diabetes and obstructive sleep apnoea (OSA) syndrome share a high prevalence in industrialized nations. The presence of OSA seems to promote the development of diabetes mellitus (DM) and vice versa. Materials and Methods: In order to assess the prevalence of sleep disordered breathing, we studied 498 patients with DM type 2 and 58 patients with DM type 1 from 15 centres, using a screening device determining airflow and pulse oximetry. Age of the patients was 59.9 ± 13.1 years, mean body mass index was 31.9 ± 6.9 kg/m². Duration of diagnosis of DM was 9.3 ± 7.3 years. Results: Among the patients, 37.4% had an apnoea‐hypopnoea index (AHI) ≥15/h suggestive of OSA. The prevalence of an AHI ≥ 15/h among the patients with DM type 1 was 10.3%. One hundred ninety‐three (35.2%) patients suffered from neuropathy. We found a higher prevalence for neuropathy, nephropathy, hypertension, cardiovascular disease and heart failure in the group with an AHI ≥ 15/h. Conclusions: The prevalence of sleep disordered breathing is increased in patients with DM. Most of these patients had no typical clinical symptoms of OSA and would have been undiagnosed without diagnostic assessment of OSA. Please cite this paper as: Schober A‐K, Neurath MF and Harsch IA. Prevalence of sleep apnoea in diabetic patients. Clin Respir J 2011; 5: 165–172.     

Analysis of the interbeat interval increment to detect obstructive sleep apnoea/hypopnoea.

The prevalence of obstructive sleep apnoea/hypopnoea syndrome (OSAHS) is underestimated and its diagnosis is costly and restricted to specialised sleep laboratories. The frequency component of interbeat interval increment (III) has been proposed as a simple and inexpensive diagnostic tool in OSAHS. In a set of 150 patients with clinically suspected sleep-related breathing disorder, the actual predictive accuracy of the power spectral density of the III of the very low frequencies (%VLFI) was analysed by comparing with the apnoea/hypopnoea index (AHI), as assessed by synchronised polysomnography. OSAHS was defined in 100 patients according to an AHI>or=15 events.h(-1). Receiver operator characteristic curves built for %VLFI confirmed that this variable was able to separate OSAHS positive from OSAHS negative with statistical significance. Using an appropriate threshold (>4%), %VLFI demonstrated a positive predictive value of 80%. Misclassification of false-positive subjects occurred when the patient presented significant sleep discontinuity and sleep fragmentation (sleep fragmentation index>or=50 events.h(-1)) related to insomnia or periodic limb movements. A power spectral density of the interbeat interval increment of very low frequencies>4% allowed correct classification of obstructive sleep apnoea/hypopnoea syndrome when the clinical history suggested sleep-related breathing disorders and when moderate-to-severe cases are considered. Higher power spectral density of the interbeat interval increment of very low frequencies may also indicate disrupted sleep in the absence of clear clinical symptoms of sleep apnoea/hypopnoea syndrome.     

Sleep‐disordered breathing in spinal cord‐injured patients: A short‐term longitudinal study

Background and objective: Previous studies have demonstrated an increased incidence of sleep apnoea in spinal cord‐injured patients. Many of these studies were performed in long‐term, stable spinal cord injury (SCI). The aims of this study were: (i) to determine the prevalence of sleep‐disordered breathing (SDB) in acute SCI; (ii) to document the change in SDB over time during the rehabilitation period; and (iii) to correlate the degree of SDB with ventilatory parameters. Methods: Sixteen subjects with an acute SCI level T12 and above with complete motor impairment (American Spinal Injury Association impairment scale A or B) were recruited. Assessment, including polysomnography, respiratory function testing, and hypoxic and hypercapnic ventilatory responses, were performed 6–8 weeks post SCI, and repeated 6 months post SCI. Results: Eleven of 16 subjects (73%) had evidence of sleep apnoea, five of whom were moderate to severe. This high incidence persisted during the acute admission, with 9 of 12 subjects (75%) having sleep apnoea on polysomnography 20 weeks following injury. There was no correlation between the severity of SDB and other measures, such as level or completeness of injury, respiratory function tests or measures of ventilatory responses. Conclusions: We have demonstrated a high incidence of sleep apnoea in the acute phase of SCI that persisted during the acute admission. Despite the high incidence of sleep apnoea, patients were relatively asymptomatic. Screening of this population would appear worthwhile given the high prevalence, although the significance of the sleep apnoea and clinical impact is not known.     

Neurocognitive impairment in Chinese patients with obstructive sleep apnoea hypopnoea syndrome

Background and objective: Sleep‐disordered breathing is known to be associated with impairment in cognitive function. The aim of this study was to characterize neurocognitive impairment in a cohort of Chinese patients with varying severities of obstructive sleep apnoea hypopnoea syndrome (OSAHS), and to develop a sensitive instrument for routine screening of cognitive impairment. Methods: Eligible patients (n = 394) were categorized into a primary snoring group, and mild, moderate and severe OSAHS groups, based on assessment of AHI. The Montreal Cognitive Assessment (MoCA) and the Mini‐Mental State Examination (MMSE) questionnaires were administered to assess cognitive function, and the correlations between questionnaire scores and clinical and polysomnographic parameters were further evaluated by stepwise multivariate regression. Results: MoCA scores decreased progressively across the spectrum from primary snoring to severe OSAHS. Importantly, mild neurocognitive impairment as defined by a MoCA score <26 was more common in the moderate (38.6%) and severe (41.4%) OSAHS groups than in the mild OSAHS (25.0%) and primary snoring (15.2%) groups. In contrast, MMSE scores were largely normal and comparable among all four groups. Evaluation of MoCA subdomains further revealed selective reduction in memory/delayed recall, visuospatial and executive function, and attention span in the severe OSAHS group compared with the other groups. Stepwise multivariate regression analysis demonstrated that MoCA scores correlated significantly with lowest oxygen saturation (L‐SaO₂) and years of education. Conclusions: Neurocognitive impairment is common in patients with OSAHS. The MoCA is a brief and sensitive tool for the assessment of cognitive impairment in OSAHS patients, whose performance on the MMSE is in the normal range.     

Prevalence of sleep-related symptoms in a primary care population - their relation to asthma and COPD.

AIMS: The aim of this study was to clarify the association between obstructive sleep apnoea/hypopnoea syndrome (OSAHS)-related symptoms and physician-diagnosed asthma and COPD. METHODS: 1501 subjects aged 19-90 years completed a structured questionnaire and underwent spirometry and respiratory physician assessment in 10 primary care centres. RESULTS: Frequent snoring was reported in 45.6%, breathing pauses during sleep in 11.0%, and excessive daytime sleepiness in 6.7% of the sample. COPD patients were more likely to report frequent snoring (OR=1.34; 95% CI:1.04-1.71), breathing pauses (OR=1.46; 95% CI:1.01-2.10), and excessive daytime sleepiness (OR=2.04; 95% CI:1.33-3.14). In contrast, there was no significant association between asthma patients and OSAHS-related symptoms. Gender differences were recognised as well. CONCLUSIONS: The increased likelihood for OSAHS-related symptoms in COPD patients, in contrast to patients with asthma, designates them as a target group for the screening of OSAHS in primary care.     

Sleep disordered breathing – a new component of syndrome x?

Sleep disordered breathing (SDB) is a complication of obesity estimated to occur in about 4–6% of overweight individuals. These respiratory disturbances during sleep incorporate a number of conditions including snoring, upper airway resistance syndrome and obstructive sleep apnoea syndrome (OSAS). It is thought that as well as having deleterious effects on sleep quality these conditions may also promote cardiovascular and hormonal changes leading to an elevated blood pressure and an increased incidence of cardiovascular morbidity. Evidence reviewed here points to an alteration in sympathovagal balance, baroreceptor sensitivity, insulin resistance and leptin, growth hormone and lipid levels. Whether these changes are a consequence of the associated obesity or the SDB itself remains to be proven.     

Restless legs syndrome: Impact on sleep‐related breathing disorders

Restless legs syndrome (RLS) is a common chronic sensory‐motor neurological disorder that remains a clinical diagnosis. Most RLS patients present with sleep complaints in the form of initiation and/or maintenance insomnia as RLS has a circadian rhythmicity. An increased number of periodic leg movements during sleep (PLMS) is a supportive criterion in the diagnosis of RLS. Abnormalities in the central dopaminergic and iron systems are involved in the physiopathology of RLS. There is a higher prevalence of RLS and PLMS in sleep‐disordered breathing patients, particularly those with obstructive sleep apnoea (OSA), the most common sleep disorder in western societies. The complex mechanisms underlying the association between OSA, RLS and PLMS remain unclear. Untreated OSA can lead to adverse cardiovascular consequences due to cardio‐metabolic dysfunction. It remains controversial whether RLS could further adversely impact the cardiovascular consequences of OSA. The PLMS do not have an additive effect on the hypersomnia experienced by some sleep‐disordered breathing patients. Continuous positive airway pressure (CPAP) therapy is the most effective therapy for OSA. The presence of PLMS during CPAP treatment could be a marker of an incomplete resolution of sleep‐disordered breathing in the form of increased upper airway resistance syndrome, despite treatment. Dopaminergic agonists are the preferred agent for the treatment of RLS, and are indicated when RLS symptoms are frequent and affect quality of life. PLMS and RLS do not seem to contribute to the residual hypersomnia that can be observed in some sleep‐disordered breathing patients despite adequate compliance and effective CPAP therapy.     

NHLBI workshop summary. Respiratory disorders of sleep. Pathophysiology, clinical implications, and therapeutic approaches

The extensive investigation into complex interactions of breathing and sleep have produced answers to numerous important questions, but it is clear that many of the most important questions in this area remain unanswered. Our understanding of the mechanisms through which sleep alters breathing and how disordered breathing can, in turn, effect sleep is rudimentary. Although a large body of recent work has done much to elucidate the factors that act to maintain the patency of the upper airway during sleep, our understanding of such mechanisms and the relative importance of structure and function in this context remains primitive. A better understanding of these issues will be critical in elucidating the pathophysiology of respiratory disorders of sleep. Although some progress has been made in this area, new insights will be critically important to the design of novel, potentially more effective approaches to treatment. Therapeutic decisions are greatly hampered by major uncertainties regarding respiratory disorders of sleep and the clinical significance of symptoms, signs, and laboratory findings, and their relationship to morbidity and mortality. It seems clear that new information regarding the pathophysiology and natural history of these disorders will be important in the development of new, more effective strategies for therapeutic intervention, and this together with rigorous, systematic evaluation of new and future therapeutic approaches will be critical to clinical progress in this field.     

Sleep and respiration in children: time to wake up!

The interest in paediatric sleep disorders over the last few decades has had its main focus on the sudden infant death syndrome (SIDS) - healthy infants who go to sleep and never wake up again. Overall, this is the most dramatic form of paediatric sleep disordered breathing. By contrast, classical presentations of sleep disordered breathing in children, such as snoring and obstructive sleep apnoea as well as their clinical implications have been greatly neglected and underestimated in the past. In contrast to snoring in adults, snoring in children has so far generally been regarded as noisy breathing with no significant impact on the general health of children. This is also to a lesser extent true for obstructive sleep apnoea syndrome (OSAS). The sometimes dramatic complications of OSAS, such as cor pulmonale and developmental retardation have at least indicated that OSAS in children is important and may have a great impact on the general health of children. This has led to an increased interest from a clinical as well as a scientific point of view with some important findings, mainly that sleep disordered breathing in childhood varies from sleep disordered breathing in adulthood and that even mild to moderate disease has a huge impact on the general health of children, mainly on neurocognitive development.     

Metabolic disturbances in obesity versus sleep apnoea: the importance of visceral obesity and insulin resistance

Obstructive sleep apnoea (OSA) is a very prevalent disorder particularly amongst middle-aged, obese men, although its existence in women as well as in lean individuals is increasingly recognized. Despite the early recognition of the strong association between OSA and obesity, and OSA and cardiovascular problems, sleep apnoea has been treated as a 'local abnormality' of the respiratory track rather than as a 'systemic illness'. In 1997, we first reported that the pro-inflammatory cytokines interleukin (IL)-6 and tumour necrosis factor-alpha (TNF alpha) were elevated in patients with disorders of excessive daytime sleepiness (EDS) and proposed that these cytokines were mediators of daytime sleepiness. Also, we reported a positive correlation between IL-6 or TNF alpha plasma levels and the body mass index (BMI). In subsequent studies, we showed that IL-6, TNF alpha, leptin and insulin levels were elevated in sleep apnoea independently of obesity and that visceral fat, was the primary parameter linked with sleep apnoea. The association of OSA with insulin resistance and diabetes type 2 has been confirmed since then in several epidemiological and clinical studies. Furthermore, our findings that women with polycystic ovary syndrome (PCOS, a condition associated with hyperandrogenism and insulin resistance) were much more likely than controls to have sleep disordered breathing (SDB) and daytime sleepiness support the pathogenetic role of insulin resistance in OSA. Other findings that support the view that sleep apnoea and sleepiness may be manifestations of a serious metabolic disorder, namely the Metabolic or Visceral Obesity Syndrome, include: obesity without sleep apnoea is associated with daytime sleepiness; PCOS and diabetes type 2 are independently associated with EDS after controlling for SDB, obesity and age; and increased prevalence of sleep apnoea in postmenopausal women, with hormonal replacement therapy associated with a significantly reduced risk for OSA. In conclusion, accumulating evidence provides support to our model of the bi-directional, feedforward, pernicious association between sleep apnoea, sleepiness, inflammation and insulin resistance, all promoting atherosclerosis and cardiovascular disease.     

Non‐invasive ventilation for obese patients with chronic respiratory failure: Are two pressures always better than one?

Obesity‐related respiratory failure is increasingly common but remains under‐diagnosed and under‐treated. There are several clinical phenotypes reported, including severe obstructive sleep apnoea (OSA), isolated nocturnal hypoventilation with or without severe OSA and OSA complicating chronic obstructive pulmonary disease (COPD). The presence of hypercapnic respiratory failure is associated with poor clinical outcomes in each of these groups. While weight loss is a core aim of management, this is often unachievable, and treatment of sleep‐disordered breathing with positive airway pressure (PAP) therapy is the mainstay of clinical practice. Although there are few long‐term clinical efficacy trials, the lack of equipoise would prevent the utilization of an untreated control group. The current data support the use of PAP therapy to improve respiratory failure and is associated with improvements in health‐related quality of life, reduced healthcare utilization and reduced mortality. Both continuous PAP (CPAP) and non‐invasive ventilation (NIV) appear safe and effective in patients with obesity‐related respiratory failure and OSA, with or without COPD, and the current evidence would not support a single therapy choice in all patients. There are no studies of CPAP in patients with isolated nocturnal hypoventilation, and NIV would be the current recommendation in this patient group. Whichever starting therapy is used, titration should be performed to correct sleep‐disordered breathing and reverse chronic respiratory failure, with consideration of step‐down of the treatment based on a clinical re‐evaluation. In contrast, failure to reach physiological and clinical treatment targets should lead to the consideration of treatment escalation.     

Monitoring respiration during sleep

The sleep-related breathing disorders have been categorized in various ways. The most basic schema divides them into obstructive or central apneic events. An American Academy of Sleep Medicine (AASM) Task Force Report published in 1999 defined four separate syndromes associated with abnormal respiratory events during sleep among adults, namely, obstructive sleep apnea-hypopnea syndrome (OSAHS), central sleep apnea-hypopnea syndrome, Cheyne-Stokes breathing syndrome, and sleep hypoventilation syndrome. In this classification, the upper airway resistance syndrome was not regarded as a distinct syndrome; instead, respiratory event-related arousals (RERAs) were considered part of the syndrome of OSAHS.     

The diagnosis of sleep-related breathing disorders

Information regarding sleep apnea syndromes and primary alveolar hypoventilation has been widely disseminated in both medical and lay publications. As a result, the pulmonary physician is confronted with a growing number of patients referred for evaluation of sleep-related breathing disorders. In addition, many pulmonary diseases may become worse during sleep. A wide variety of diagnostic options is available. The method chosen will depend on availability, cost, and the strength of the clinical impression. Screening studies, from the most simple (night-time Holter monitor or ear oximetry) to either a carefully performed nap study or a home recording may aid in deciding which patients require a formal polysomnogram. Centers with full all-night study capability may not use preliminary recordings at all. Because many therapeutic modalities exist, their intelligent use requires an accurate assessment of the type and severity of the breathing disorder.     

物联网在睡眠呼吸紊乱管理中的应用

睡眠呼吸紊乱包括一组疾病,其中OSAHS是最常见的类型,而针对此病的长期有效管理非常关键.物联网医学是一种新型的远程医学模式,它的出现为睡眠呼吸紊乱管理提供了新的技术平台.文中就物联网医学的定义和优点,以及物联网在OSAHS诊断、筛查、治疗随访和患者/医务人员教育中的应用作一综述.     

A high prevalence of sleep disordered breathing in men with mild symptomatic chronic heart failure due to left ventricular systolic dysfunction

BACKGROUND: Sleep disordered breathing (SDB) is common in severe chronic heart failure (CHF) and is associated with increased morbidity and mortality. The prevalence of SDB in mild symptomatic CHF is unknown. AIM: The aim of this study was to determine the prevalence and characteristics of SDB in male patients with NYHA class II symptoms of CHF. METHODS AND RESULTS: 55 male patients with mild symptomatic CHF underwent assessment of quality of life, echocardiography, cardiopulmonary exercise, chemoreflex testing and polysomnography. 53% of the patients had SDB. 38% had central sleep apnoea (CSA) and 15% had obstructive sleep apnoea. SDB patients had steeper VE/VCO(2) slope [median (inter-quartile range) 31.1 (28-37) vs. 28.1 (27-30) respectively; p=0.04], enhanced chemoreflexes to carbon dioxide during wakefulness [mean+/-sd: 2.4+/-1.6 vs. 1.5+/-0.7 %VE Max/mmHg CO(2) respectively; p=0.03], and significantly higher levels of brain natriuretic peptide and endothelin-1 compared to patients without SDB. No differences in left ventricular ejection fraction, percent predicted peak oxygen uptake, or symptoms of SDB were observed. CONCLUSIONS: A high prevalence of SDB was found in men with mild symptomatic CHF. Patients with SDB could not be differentiated by symptoms or by routine cardiac assessment making clinical diagnosis of SDB in CHF difficult.     

茶碱缓释胶囊对轻中度阻塞型睡眠呼吸暂停低通气综合征的影响

目的观察轻中度阻塞型睡眠呼吸暂停低通气综合征(OSAHS)患者口服氨茶碱前后睡眠参数变化情况。方法随机选择60例经多导睡眠图(PSG)监测确诊的轻中度OSAHS患者,入选对象随机分成A、B两组,A组30例,给予口服茶碱缓释胶囊0.2/晚,B组30例,给予安慰剂口服。比较未给药、口服茶碱后、口服安慰剂后睡眠监测指标变化情况,包括:睡眠呼吸暂停低通气指数(apnea hypopnea index,AHI)、最低夜间血氧饱和度(LSaO_2)、平均夜间血氧饱和度(MSaO_2)、SaO_290%时间、睡眠呼吸障碍最长时间,同时监测茶碱血药浓度,观察药物不良反应发生情况。结果 (1)口服茶碱后LSaO_2:90.4%±2.1%,MSaO_2:92.2%±1.5%,SaO_290%时间(34.3±10.2)秒,睡眠呼吸障碍最长时间(25.0±2.3)秒,较未给药LSaO_2:86.2%±2.6%,MSaO_2:89.1%±1.8%,SaO_290%时间(45.1±18.6)秒,睡眠呼吸障碍最长时间(32.0±5.0)秒及给予安慰剂后LSaO_2:85.3%±3.8%,MSaO_2:90.8%±2.6%,SaO_290%时间(39.2±19.8)秒,睡眠呼吸障碍最长时间(31.0±3.4)秒,均有显著差异(P0.017)。但AHI改变无统计学差异。口服安慰剂与未给药时比较,睡眠监测指标差异无统计学意义。(2)口服茶碱缓释胶囊,观察药物不良反应发生1例,表现为恶心,监测茶碱血药浓度在安全范围,停药后症状缓解。结论轻中度OSAHS睡前口服茶碱缓释胶囊安全有效,可缩短睡眠呼吸障碍最长时间,改善夜间LSaO_2、MSaO_2、SaO_290%时间。     

New Technologies to Detect Static and Dynamic Upper Airway Obstruction During Sleep

Increase in upper airway resistance is the main patho-physiological feature in the obstructive breathing disorders during sleep. Upper airway events may be divided into two main groups: static obstruction (apneas) and dynamic obstruction (hypopneas, flow limitation, and snoring). This classification is useful to provide better information about the patho-physiological mechanisms of obstruction and to better define the diagnostic tools necessary for detecting abnormal respiratory events during sleep. Detection of dynamic obstruction requires sensors with a good frequency response. As thermistors have a poor dynamic response, they are not efficient in detecting the dynamic obstruction but are good enough to detect static obstruction. Nasal prongs (NP) connected a to pressure transducer and the impedance signal measured by the forced oscillation technique (FOT) are relatively new tools to noninvasively investigate dynamic upper airflow obstruction during sleep. FOT provides a direct index of the magnitude of airway obstruction and, therefore, of the upper airway patency, even under conditions of no flow (apneas). NP are aimed at assessing flow. Thus, both techniques have a different scope. The main advantages of NP are that they are easy to use and do not require sophisticated technology, while FOT needs a more complex instrumentation. For clinical routine studies NP are probably the best and simplest method for assessing the different respiratory events during sleep. However, FOT would be particularly useful in selected applications such as assessing upper airway patency in some central apneas; interpreting the irregular pattern of breathing during REM sleep; in better characterizing the inspiratory flow-limited breaths classified as intermediate; and in studying upper airway mechanics.     

OSAHS患者呼吸障碍的差异及SaO2检测的诊断价值

目的探索连续血氧饱和度(SaO2)检测是否对阻塞性睡眠呼吸暂停低通气综合症(OSAHS)有诊断价值,以及不同程度OSAHS患者之间的呼吸障碍的差异。方法对104例鼾症患者进行多导睡眠图(PSG)的检测,分为单纯鼾症、轻、中、重度OSAHS共4组,收集资料并分析。结果1各OSAHS组SaO2的基础值和最低值均小于单纯鼾症组(P均<0.05);2所有患者的SaO2的基础值和最低值均与睡眠呼吸暂停低通气指数(AHI)呈显著负相关(R=-0.478,-0.507;P均<0.05);3OSAHS患者的SaO2的基础值和最低值均与AHI呈显著负相关(R=-0.315,-0.334;P均<0.05);4所有患者的SaO2的基础值和最低值均与体重指数(BMI)呈显著负相关(R=-0.579,-0.601;P均<0.05);5若以SaO2基础值<95%和SaO2<85%作为诊断OSAHS的标准,敏感性分别是78.5%和73.8%;特异性均是100%;6各OSAHS组睡眠呼吸障碍在不同睡眠期的分布不同。结论OSAHS患者存在睡眠时SaO2下降,并与疾病的严重程度有关;连续检测SaO2是在鼾症患者中鉴别出OSAHS的一个有效的简易方法;各OSAHS组睡眠呼吸障碍在不同睡眠期的分布不同。