Increased prevalence of perennial allergic rhinitis in patients with obstructive sleep apnea

BACKGROUND: Impaired nasal breathing is a risk factor for obstructive sleep apnea syndrome (OSAS). OBJECTIVES: The aim of this study was to determine whether atopy to perennial allergens and existence of perennial allergic rhinitis was a risk factor for OSAS. METHODS: In a case-control study, we compared the proportions of OSAS patients with atopy to perennial allergens and perennial allergic rhinitis to the proportions in patients with chronic obstructive pulmonary disease (COPD). Seventy-two OSAS patients (mean age 60.7 years; 79.4% male) and 44 COPD patients (mean age 63.6 years; 88.6% male) were selected from a hospital outpatients' clinic in Switzerland. All patients completed a respiratory symptom questionnaire, performed spirometry and had a skin prick test for atopy. RESULTS: OSAS patients were significantly heavier than COPD patients (BMI 32.4 +/- (SD) 6.6 vs. 29.2 +/- 6.6 kg/m2, p = 0.04) and had a better lung function than COPD patients (FEV1% predicted 91.3 +/- 19.2 vs. 51.6 +/- 18.9%, p < 0.001). Patients with OSAS were more likely to be sensitized to perennial allergens such as house dust mite (23.6 vs. 4.5%, p = 0.009) and dog (18 vs. 4.5%, p = 0.04) than the COPD patients. Perennial allergic rhinitis (having nose problems [nasal obstruction and/or runny nose and/or sneezing] all year and being atopic to at least one perennial allergen) was reported in 11% of OSAS patients but in only 2.3% of COPD patients (p = 0.15). CONCLUSION: We conclude that subjects with OSAS may have an increased risk of being allergic to perennial allergens and suffer from perennial rhinitis. Awareness of this risk may have important consideration in the clinical situation.     

A review of 50 children with obstructive sleep apnea syndrome

Fifty children and adolescents with obstructive sleep apnea syndrome and related breathing disorders during sleep are reviewed. Subjects were subdivided according to whether their breathing irregularity was secondary to a medical problem (group I) or was the primary complaint (group II). The most common presenting complaint was excessive daytime somnolence; hyperactivity and antisocial behavior also were cited frequently. In 20% of cases, substantial personality changes were reported. Clinical symptoms included failure to thrive, abnormal weight for age, acute cardiac or cardiorespiratory failure, hypertension, and frequent upper airway infections. Continuous, heavy snoring was reported in all cases; disrupted nocturnal sleep, sleep walking, nightmares, and enuresis were common. All subjects, and 22 control patients, were monitored polygraphically during sleep for at least one night. Nocturnal sleep in the reported population was severely disrupted. A complete disappearance of stage 3 NREM sleep was noted in 86% of cases; REM sleep was decreased less. The management of these cases is reviewed. Eight patients received permanent tracheostomies. Thirty children had tonsillectomy and/or adenoidectomy (three later required tracheostomy). Non-surgical approaches also were used, particularly in group 1. Follow-up on these cases to date is presented.     

睡眠呼吸暂停低通气综合征问卷对阻塞性睡眠呼吸暂停综合征诊断价值

目的 评价阻塞性睡眠呼吸暂停低通气综合征(OSAHS)的流行病学调查表筛查价值.方法 疑似OSAHS的987例患者为研究对象,按照中华医学会呼吸病学分会睡眠学组睡眠呼吸暂停低通气综合征流行病学调查表进行问卷并行多导睡眠监测.将此问卷表进行量化评分,用克隆巴赫信度系数(α系数)进行信度计算,将各相关因素做方差分析及x2检验,筛选出有统计学意义的因素最后做Logistic回归分析.以鼾声中度以上的打鼾及体质量指数≥25 kg/m2为高危,反之为低危,进行敏感性,特异性,假阳性,假阴性,阳性似然比,阴性似然比,阳性预测值等.结果 疑似OSAHS患者987例,其中男800例(81.05％),女187例(18.95％),年龄18～80岁,平均(47±12)岁,平均体质量指数(29±5) kg/m2.＞60岁者156例(15.81％),≤60岁者831例(84.19％).克隆巴赫信度系数(Cronbach'salpha)是0.803,假阳性者20,假阴性者142,真阳性者742,真阴性者83,问卷的敏感性是83.94％,特异性是80.58％,假阳性率19.42％,假阴性率16.06％,阳性似然比4.32,阴性似然比0.20,阳性预测值0.97,阴性预测值0.37,正确率83.59％.结论 该睡眠调查表对OSAHS筛查具有一定意义,可用于临床OSAHS的初筛,尤其适合在社区和基层医院中推广使用.     

Clinical evaluation in predicting childhood obstructive sleep apnea

OBJECTIVE: To determine whether parents' observation, clinical examination, and lateral upper airway radiograph are useful in detecting clinically significant obstructive sleep apnea (OSA) in children. METHOD: We retrospectively reviewed data of 50 children aged 4 to 18 years who were consecutively referred to a sleep clinic for suspected OSA. All subjects underwent clinical assessments including standardized history collection, physical examination, and lateral neck radiograph for measurement of postnasal space. Each child underwent overnight polysomnography on the night of clinical assessments. Patients with clinically significant OSA, defined as apnea-hypopnea index (AHI) > 5, were compared with primary snorers, defined as AHI < or = 5. RESULTS: Thirty-one children had clinically significant OSA, and 19 children were primary snorers. The prevalence of risk factors including allergic rhinitis, obesity, and craniofacial anomaly was similar between the two groups. Observable apnea during sleep, nocturnal enuresis, intrusive naps, mouth breathing, enlarged tonsils, and radiologic features of upper airway narrowing due to adenoid hypertrophy were found to be predictors for clinically significant OSA. Combining upper airway narrowing and mouth breathing or nocturnal enuresis had a sensitivity of 90.3%, and combining all six predictors had a sensitivity of 93.5% of detecting OSA. CONCLUSION: Combining clinical and radiologic findings might be helpful to screen for children with clinically significant OSA who need earlier investigation and intervention.     

Heart rate variability in childhood obstructive sleep apnea

The identification of patients with obstructive sleep apnea (OSA) is important because of morbidities associated with OSA. A previous adult study demonstrated the use of heart rate variability (HRV) as a tool to identify patients with moderate to severe OSA. Either a reduction in time parameters or an increase in LF/HF ratio was seen at overnight or 24‐hr studies suggestive of increased sympathetic modulation. To study the feasibility of daytime HRV as a screening tool, a short‐term recording of HRV is studied. Since it was shown in adult study that increased normalized LF, decreased normalized HF and increased LF/HF ratio could be detectable during supine rest at daytime awake period, the authors hypothesize that the differences are also detectable in children. Children who underwent sleep polysomnography for suspected OSA were recruited. Subjects were classified OSA if apnea‐hypopnea index (AHI) > 1.5/hr and non‐OSA if AHI ≤ 1.5/hr. Continuous 1‐hr electrocardiographic monitoring was recorded in awake children during the day. Parameters from time domain and frequency domain were analyzed. Seventy‐four male and 17 female snoring subjects were included in this study. Fifty‐one (56%) and 40 (44%) of them were classified as “non‐OSA” and “OSA,” respectively. pNN50, a parameter for parasympathetic modulation, was significantly reduced in the OSA group when compared with the non‐OSA group. Using multiple regression, all time domain variables were shown to be decreased in OSA group. Our results suggest that 1‐hr study of HRV may be a feasible tool in identifying children with OSA. Pediatr Pulmonol. 2011; 46:205–210. © 2011 Wiley‐Liss, Inc.     

Women and the obstructive sleep apnea syndrome

Twenty-seven women referred to a sleep disorders clinic for symptoms of obstructive sleep apnea syndrome (OSAS) during one year were systematically analyzed after polygraphic monitoring of sleep and cephalometric x-ray examination. Our subjects, one-third of whom were premenopausal, comprised approximately 12 percent of the total OSAS population seen. Women with OSAS were compared with 110 OSAS men and with a group of 16 women without OSAS but referred to orthodontists for mild dental malocclusion. Women with OSAS were massively obese, much more so than their male counterparts. There was no significant difference between pre- and postmenopausal women, with the exception of the respiratory disturbance index (RDI), which was lower in the postmenopausal group despite similar morbid obesity (seemingly better tolerated by women with OSAS than by men with the same syndrome) and long mandibular plane-hyoid bone distance. The significantly higher RDI noted in premenopausal women, despite equally massive obesity and upper airway abnormalities, is thought to be related to hormonal status and better arousal response. Chronic obstructive lung disease (COLD) seen in a subgroup of women with OSAS did not differentiate this subgroup from the other OSAS patients when oxygen saturation during sleep, frequency of abnormal respiratory events and sleep variables were considered. Massive obesity is the dominant factor for the appearance of OSAS in women.     

Decreased lipoprotein lipase in obstructive sleep apnea syndrome.

BACKGROUND: Lipoprotein lipase (LPL) might play a major role in lipid metabolism by hydrolyzing triglyceride-rich lipoproteins. Decreased LPL activity can trigger early inflammatory responses central to atherosclerosis. However, whether repeated apnea-related hypoxemia influences lipid metabolism in patients with obstructive sleep apnea syndrome (OSAS) remain undefined. This investigation determined whether circulating LPL was influenced by repeated apnea-related hypoxemia, and the effect of nasal continuous positive airway pressure (CPAP) therapy on LPL concentrations in OSAS patients. METHODS AND RESULTS: The participants of the study were 155 men with OSAS and 39 men without OSAS. Circulating LPL concentrations decreased with the severity of OSAS. They correlated negatively with serum triglyceride, and the linear regression lines between LPL concentrations and triglyceride in OSAS patients were shifted downward compared with those in non-OSAS patients, suggesting that any pathophysiological factor might decrease LPL activity in OSAS patients. Some OSAS patients were subjected to CPAP therapy for 3 months. CPAP therapy increased LPL concentrations and decreased C-reactive protein (CRP) concentrations. CONCLUSIONS: The present study suggests that repeated apnea-related hypoxemia might affect lipid metabolism and augment inflammatory responses, and CPAP therapy could be effective to decrease inflammatory responses and ameliorate lipid metabolism in patients with OSAS.     

阻塞性睡眠呼吸暂停综合征与心律失常

阻塞性睡眠呼吸暂停综合征（ＯＳＡＳ）对心血管功能的影响越来越引起人们的关注。为探讨ＯＳＡＳ与心律失常的关系，我们对２１２例打鼾者行夜间多导睡眠图监测（ＰＳＧ），呼吸紊乱指数（ＡＨＩ）≥５为ＯＳＡＳ。分析ＰＳＧ心电导联。结果：１４６例病人诊断为ＯＳＡＳ，其中８２例ＯＳＡＳ病人发生心律失常（５６．２％），包括早搏或心动过速、传导阻滞或二者均有。采用经鼻持续气道内正压呼吸（ｎＣ－ＰＡＰ）７小时治疗严重的ＯＳＡＳ合并心律失常１９例，其中治疗后心律失常完全消失者１４例（７３．７％）。ＯＳＡＳ病人的心律失常发生率较非ＯＳＡＳ高（χ２＝１７．２８，Ｐ＜０．０００１）。心律失常发生率与低氧及夜间呼吸暂停严重程度呈正相关。ｎＣＰＡＰ有效治疗呼吸暂停的同时可逆转或改善心律失常。作者认为，低氧血症很可能是ＯＳＡＳ者心律失常的重要原因之一。     

Masked hypertension in obstructive sleep apnea syndrome

BACKGROUND: Ambulatory blood pressure (BP) monitoring (ABPM) detects subjects with normal clinic but high ambulatory 24-h BP, that is, masked hypertension. METHODS: One hundred and thirty newly diagnosed obstructive sleep apnea syndrome (OSAS) patients, free of recognized cardiovascular disease were included (111 men, age = 48 +/- 1 years, BMI = 27.6 +/- 0.4 kg/m, respiratory disturbance index (RDI = 42 +/- 2/h). Clinic BP, 24-h ABPM, baroreflex sensitivity (BRS), echocardiography and carotid intima-media thickness (IMT) were assessed. RESULTS: Forty-one patients (31.5%) were normotensive, 39 (30.0%) exhibited masked hypertension, four (3.1%) white-coat hypertension and 46 (35.4%) hypertension. Significant differences were found between normotensive, masked hypertensive and hypertensive patients in terms of BRS (10.5 +/- 0.8, 8.0 +/- 0.6 and 7.4 +/- 0.4 ms/mmHg, respectively, P < 0.001), carotid IMT (624 +/- 17, 650 +/- 20 and 705 +/- 23 microm, respectively, P = 0.04) and left ventricular mass index (37 +/- 1, 40 +/- 2 and 43 +/- 1 g/height2.7, respectively, P = 0.003). A clinic systolic BP more than 125 and a diastolic BP more than 83 mmHg led to a relative risk (RR) of 2.7 and a 90% positive predictive value for having masked hypertension. CONCLUSION: Masked hypertension is frequently underestimated in OSAS and is nearly always present when clinic BP is above 125/83 mmHg.     

Metabolic syndrome in Japanese patients with obstructive sleep apnea syndrome.

We investigated the prevalence of metabolic syndrome in patients with obstructive sleep apnea syndrome (OSAS) referred to a tertiary university-based medical center. A cross-sectional study of patients with a definite diagnosis of OSAS was performed using new diagnostic criteria for metabolic syndrome that were designed for the Japanese population. Clinical features and comorbidities related to metabolic syndrome were compared between 819 patients with OSAS (719 men and 100 women) and 89 control subjects without OSAS. Metabolic syndrome was significantly more common in the patients with OSAS than in the controls (49.5% vs. 22.0% for men, p < 0.01; 32.0% vs. 6.7% for women, p < 0.01). Men with OSAS (apnea-hypopnea index [AHI] > or =5/h) had a higher risk of metabolic syndrome compared with controls (odds ratio [OR]: 3.47; 95% confidence interval [CI]: 1.84-6.53). There was a significantly increased risk of metabolic syndrome in men with moderate OSAS (AHI: 15-29.9/h) (OR: 2.83; 95% CI: 1.42-5.66) and men with severe OSAS (AHI > or =30/h) (OR: 5.09; 95% CI: 2.67-9.71). Women with OSAS (AHI> or =5/h) also had an increased risk of metabolic syndrome (OR: 6.59; 95% CI: 1.47-29.38), and the risk was significantly higher in women with severe OSAS (AHI > or =30/h) (OR 14.00; 95% CI: 2.93-66.82). Risk factors for metabolic syndrome differed by gender: in men, age, body mass index (BMI), and OSAS (AHI > or =15/h) were significantly associated with metabolic syndrome, whereas, in women, BMI was the only risk factor for metabolic syndrome. The increase of metabolic syndrome in Japanese OSAS patients suggests that this patient population is burdened with multiple risk factors for cardiovascular disease.     

阻塞性睡眠呼吸暂停综合征患者胰岛素敏感性的变化

目的 研究阻寒性睡眠呼吸暂停低通气综合征(OSAHS)患者胰岛素敏感性(IS)的变化.方法 55例男性鼾症患者行整夜睡眠呼吸监测,放免法测定FIns,C-P水平,计算ISI和QUICKI观察患者IS变化. 结果 随呼吸紊乱指数(AHI)增加,OSAHS患者胰岛素抵抗(IR)和肥胖的程度越来越明显.多元逐步线性回归分析结果提示BMI、最低血氧饱和度和AHI是IS下降的独立危险因素.OS-AHS患者持续气道正压通气治疗1个月后IS无明显变化. 结论 严重呼吸紊乱常与肥胖、IR合并存在.睡眠呼吸紊乱可能足IR的独立危险因素.     

Daytime hypercapnia in obstructive sleep apnea syndrome

BACKGROUND: The pathogenesis of daytime hypercapnia (Paco2 >or= 45 mm Hg) may be directly linked to the existence of obstructive sleep apnea syndrome (OSAS) per se, although only some patients with OSAS exhibit daytime hypercapnia. OBJECTIVE: To investigate the prevalence of daytime hypercapnia in patients with OSAS; the association of daytime hypercapnia and obesity, obstructive airflow limitation, restrictive lung impairment, and severity of sleep apnea; and the response to continuous positive airway pressure (CPAP) therapy in a subset of subjects. METHODS: The study involved 1,227 patients with OSAS who visited a sleep clinic and were examined using polysomnography. As for the response to CPAP therapy, the patients were considered good responders if their daytime Paco2 decreased >or= 5 mm Hg and poor responders if it decreased < 5 mm Hg. RESULTS: Fourteen percent (168 of 1,227 patients) exhibited daytime hypercapnia. These patients had significantly higher body mass index (BMI) and apnea-hypopnea index (AHI) values compared with normocapnic patients, while percentage of predicted vital capacity (%VC) and FEV(1)/FVC ratio did not differ between the two groups. Logistic regression analysis showed that only AHI was a predictor of daytime hypercapnia (p < 0.0001), while BMI (p = 0.051) and %VC (p = 0.062) were borderline predictors of daytime hypercapnia. Daytime hypercapnia was corrected in some patients (51%, 19 of 37 patients) with severe OSAS after 3 months of CPAP therapy. CONCLUSION: The pathogenesis of daytime hypercapnia may be directly linked to sleep apnea in a subgroup of patients with OSAS.     

Vascular reactivity in obstructive sleep apnea syndrome

The obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular disease and systemic hypertension. Because systemic arterial blood pressure is proportional to venodilation and venous return to the heart, we hypothesized that altered vascular responsiveness might exist in the veins of subjects with OSAS. We therefore investigated venodilator responses in awake, normotensive subjects with and without OSAS, using the dorsal hand vein compliance technique. Dose-response curves to bradykinin and nitroglycerin were obtained from 12 subjects with OSAS and 12 matched control subjects. Maximal dilation (E(max)) to bradykinin was significantly lower in the OSAS group (62.1% +/- 26.1%) than in the control group (94.3% +/- 10.7%) (p < 0.005). Vasodilation to nitroglycerin tended to be lower in the OSAS group (78.6% +/- 31.8%) than the control group (100.3% +/- 12.9%), but this effect did not reach statistical significance. When six of the OSAS subjects were retested after 60 d of treatment with nasal continuous positive airway pressure (CPAP), E(max) to bradykinin rose from 60.3% +/- 20. 3% to 121.4% +/- 26.9% (p < 0.01). Vasodilation to nitroglycerin also increased, but this effect did not reach statistical significance. These results demonstrate that a blunted venodilatory responsiveness to bradykinin exists in OSAS. This effect appears to be reversible with nasal CPAP therapy.     

Reversible proteinuria in obstructive sleep apnea syndrome

Two patients with severe obstructive sleep apnea syndrome and high-grade proteinuria (greater than 1 g/d [1000 mg/d]) were studied. Three remissions in proteinuria coincided with correction of obstructive sleep apnea syndrome and improvement of blood oxygen levels. These remissions could be dissociated from reductions both in dry body weight and in hematocrit levels. We propose that sleep apnea may cause a functional and reversible type of proteinuria.     

Maintenance of wakefulness test in obstructive sleep apnea syndrome.

The usefulness of a 40-min per trial version of the maintenance of wakefulness test was assessed in 322 patients with obstructive sleep apnea. This test is a variant of the multiple sleep latency test in which patients are asked to remain awake in a quiet darkened room, and then monitored for electroencephalographic sleep onset. The four trials of the test are each stopped after 40 min. The mean sleep latency for all patients was 26.0 +/- 11.8 (SD) min. In a group of 24 patients who underwent treatment with nasal continuous positive airway pressure, the mean sleep latency increased from 18.0 +/- 12.3 to 31.9 +/- 10.4. The strongest nocturnal correlates of the MWT sleep latency were respiratory arousal index (r = -.35), mean oxygen saturation (r = .30), and weight/height ratio (r = -.25). These correlations were comparable to other studies using the MSLT. There were strong intercorrelations among the variables. In the more severe groups, measures of hypoxemia were more strongly correlated with MWT sleep latency. A two-factor analysis of variance using respiratory arousal index and several measures of oxyhemoglobin saturation indicated that both arousals from sleep and degree of hypoxemia contribute interactively to daytime dysfunction in patients with sleep apnea. The MWT appears useful in evaluating disability from daytime sleepiness.