Lung aeration during sleep in patients with obstructive sleep apnoea

Background: Previous studies have indicated that patients with obstructive sleep apnoea (OSA) have altered ventilation and lung volumes awake and the results suggest that this may be a determinant of severity of desaturations during sleep. However, little is known about regional lung aeration during sleep in patients with OSA. Methods: Twelve patients with OSA were included in the study. Computed tomography was used to study regional lung aeration during wakefulness and sleep. Lung aeration was calculated in ml gas/g lung tissue in four different regions of interest (ROI_1–4), along the border of the lung from ventral to dorsal. Results: Lung aeration in the dorsal (dependent) lung region (ROI₄) was lower during sleep compared to wakefulness 0·78 ± 0·19 versus 0·88 ± 0·19 (mean ± SD) ml gas/g lung tissue (P = 0·005). Associations were found between awake expiratory reserve volume and change in lung aeration from wakefulness to sleep in ROI₄ (r = ?0·69; P = 0·012). In addition, the change in lung aeration in the dorsal region correlated to sleep time (r = 0·69; P = 0·014) but not to time in supine position. The difference in lung aeration between inspiration and expiration (i.e. ventilation), was larger in the ventral lung region when expressed as ml gas per g lung tissue. In two patients it was noted that, during on‐going obstructive apnoea, lung aeration tended to be increased rather than decreased. Conclusions: Aeration in the dorsal lung region is reduced during sleep in patients with OSA. The decrease is related to lung volume awake and to sleep time.     

Treatment of obstructive sleep apnoea as a therapeutic modality for associated erectile dysfunction

Aim: This study aimed to determine the impact of long‐term treatment with continuous positive airway pressure (CPAP) and obstruction relieving surgical procedure on obstructive sleep apnoea syndrome (OSAS) patients on erectile function (EF). Methods: Eighty male OSAS patients, suffering from erectile dysfunction (ED) were studied. The severity of OSAS was determined by evaluation of daytime sleep tendency using the Epworth Sleepiness Scale (ESS), measure of minimal oxygen saturation (SaO₂) percentage and the frequency of apnoea‐hypopnea index (AHI) during sleep. EFs were assessed using five‐question International Index of Erectile Function (IIEF‐5) questionnaire. The nocturnal penile rigidity of the patients was evaluated using automated Rigiscan. Results: Patients were subjected to CPAP every night for 3 months. After 3 months of CPAP treatment, the patients showed significant improvements in ESS and recorded much lower SaO₂ percentages compared with their pre‐treatment measures. Moreover, post‐treatment AHIs were significantly lower, compared with pre‐treatment indexes. Post‐treatment evaluation of EFs showed significant improvements. Conclusions: In summary, OSAS in male patients can be considered as an underlying pathogenic factor for later development of ED. Therefore, its treatment can induce significant improvement in patients’ EF. The mechanism underlying ED in patients with OSAS remains unclear. However, nasal CPAP, which is the gold standard in treatment of OSAS patients, and obstruction relieving surgery have been found effective in improving sexual performance and quality of life.     

阻塞性睡眠呼吸暂停低通气综合征引起男性性功能障碍危险因素分析

目的 探讨男性阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者性功能障碍的危险因素.方法 采用国际勃起功能指数量表(IIEF-5)评估121例男性22～50岁OSAHS患者性功能,分为性功能正常组(65例)和性功能障碍组(56例).比较两组患者临床资料和多导睡眠图监测结果.部分性功能障碍患者进行持续气道正压(CPAP)治疗后再次以IIEF-5评价性功能.结果 性功能障碍组患者体质量指数(BMI)显著高于性功能正常组[(31.5±3.9) kg/m2与(30.1±3.5) kg/m2,t=6.897,P＜0.01],有糖尿病病史者显著多于性功能正常组(18例与10例,x2=4.750,P＜0.05),晨间血压升高者显著多于性功能正常组(38例与27例,x2 =8.381,P＜0.01);性功能障碍组患者多导睡眠图监测显示,呼吸紊乱指数(RDI)、最长呼吸暂停时间(Tmax)、最低脉搏血氧饱和度(LSp02)、脉搏血氧饱和度低于90％时间占总睡眠(TST)时间比(T90％)、浅睡眠(S1+S2)占ST比、深睡眠(S3+S4)占TST比、快动眼睡眠(REM)占TST比等指标与性功能正常组之间差异有统计学意义(t值分别为5.290、2.253、3.770、7.536、6.599、3.935和5.536,P均＜0.05).多因素Logistic回归分析显示,糖尿病病史、多导睡眠图监测中S1 +S2占TST比、RDI和LSp02对男性OSAHS患者出现性功能障碍有统计学意义,其OR值(95％可信区间)分别为2.10(1.17 ～5.01)、3.52(1.33 ～ 5.97)、1.45(1.08 ～2.95)和0.86(0.67～0.93),P均＜0.05.20例性功能障碍患者持续气道正压治疗2个月后14例经IIEF-5评分(＞21分)正常.结论 具有糖尿病病史,睡眠结构紊乱S1 +S2占TST比增多、RDI较高和LSpO2较低是男性OSAHS患者发生性功能障碍的独立危险因素.持续气道正压治疗可以显著改善男性OSAHS患者性功能.     

Pharyngeal size and shape during wakefulness and sleep in patients with obstructive sleep apnoea

Computed tomography has been used to study the pharyngeal airway during tidal breathing in wakefulness and during obstructive apnoeas in Non-REM sleep in patients with obstructive sleep apnoea. In supine subjects, contiguous transverse 10 mm sections were taken perpendicular to the posterior pharyngeal wall with a 2.1 s scan time. Studies during wakefulness showed that the narrowest section of the pharyngeal airspace was in the region posterior to the soft palate and that the minimal airway cross-sectional areas were significantly reduced in the group of patients with obstructive sleep apnoea compared to the group of control subjects without obstructive sleep apnoea. The studies during sleep showed that in all patients, the airspace posterior to the soft palate was a site of obstructive apnoeas. The length of the obstructed segment varied between patients, extending below the level of the soft palate in half the patient group. Airway narrowing and obstruction was due to posterior displacement of the soft palate and the tongue in the majority of patients, although lateral displacement of the pharyngeal walls was also observed. No occlusion was observed in the laryngopharynx although there was narrowing of oro- and laryngopharyngeal apertures below the site of obstruction during obstructive apnoeas. The size of the oropharyngeal airspace during wakefulness did not predict the presence of airway occlusion below the level of the soft palate when asleep. The variability between patients in the site(s) of upper airway obstruction during obstructive apnoeas have important implications for the choice of appropriate treatment in patients with obstructive sleep apnoea.     

Inspiratory flow limitation in obstructive sleep apnoea patients

Patients suffering from the obstructive sleep apnoea syndrome (OSAS) experience nocturnal episodes of upper airway obstruction resulting in recurrent oxygen desaturations and arousals. Methods to quantify the nocturnal obstructive events are of interest for characterizing this prevalent sleep disorder. In a study published in this issue of Clinical Science, Bloch and co-workers propose the computation of a new index for objectively quantifying the degree of flow limitation in patients with OSAS. The results obtained in a bench test and in a pilot study in patients suggest that the flow limitation index proposed may help to better characterize the disturbed breathing events undergone by patients with OSAS.     

冠心病合并阻塞性睡眠呼吸暂停患者的血液生化指标分析

目的探讨冠心病合并阻塞性睡眠呼吸暂停(obstructive sleep apnea,OSA)患者的多项血液生化指标的变化,旨在为合并有OSA的冠心病患者的治疗提供依据。方法 178例冠心病患者经多导睡眠监测(polysomnogra-phy,PSG),依据呼吸暂停低通气指数(apnea-hypopnea index,AHI),分为四组:OSA阴性组、轻度OSA组、中度OSA组、重度OSA组;检测各组患者的空腹血糖(FG)、糖化血红蛋白(HBA1c)、高敏C-反应蛋白(hsCRP)、氨基末端B型钠尿肽原(NT-proBNP)、血清甘油三酯(TG)、总胆固醇(TCHO)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)等指标,并将检测结果在各组间做比较。结果 FG在重度OSA组高于OSA阴性组、轻度OSA组和中度OSA组,差异有统计意义(P值分别为0.006、0.000、0.002),且随着OSA的加重而逐步增高;HBA1c在重度OSA组也高于其他三组,差异有统计意义(P值分别为0.004、0.001、0.023),且随着OSA的加重而逐步增高;hsCRP在OSA重度组高于OSA阴性组,差异有统计意义(P=0.040);NT-proBNP、TG、TCHO、HDL-C、LDL-C等各项目组间比较差异均无统计意义(P>0.05)。结论冠心病合并OSA的患者糖代谢紊乱突出;冠心病合并重度OSA的患者存在慢性系统性炎症。对合并有OSA的冠心病患者除常规冠心病、OSA治疗外,应早期筛查糖耐量,采取积极的降糖、抗炎症措施可能对其有益。     

Spinal manual therapy interventions for pediatric patients: a systematic review

Objective:

Although much has been written about the efficacy of manual therapy interventions for adults with headaches or spinal pain, little research has focused on the use of these interventions in pediatric patients. The purpose of this systematic review was to evaluate the evidence for spinal manual therapy (SMT) interventions in patients 4–17 years old with headaches and/or mechanical spinal pain.

Methods:

A search for relevant studies published in the past 15 years was conducted on MEDLINE, CINAHL, Cochrane Central Register of Randomized Control Trials, PEDro, PubMed, and Sports Discus. Only English language articles were reviewed. Studies had to include at least one outcome measure for pain, function, or quality of life. Studies evaluating post-operative interventions, or those in which the interventions were directed at influencing excessive spinal curvatures, were excluded. Case reports and studies that did not limit analysis of the results to the pediatric population were also excluded. Results: Two randomized control trials and two studies offering lower levels of evidence were identified in the literature search. The latter studies were prospective cohort studies. The four studies were evaluated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria.

Discussion:

There are very little data in the literature to support or refute the use of SMT interventions in pediatric patients. Further research is required to establish a strong evidence-based foundation for use of these interventions in children.     

The effect of a very low-calorie diet-induced weight loss on the severity of obstructive sleep apnoea and autonomic nervous function in obese patients with obstructive sleep apnoea syndrome

The aim of this study was to examine the effect of a very low-calorie diet (VLCD)-induced weight loss on the severity of obstructive sleep apnoea (OSA), blood pressure and cardiac autonomic regulation in obese patients with obstructive sleep apnoea syndrome (OSAS). A total of 15 overweight patients (14 men and one woman, body weight 114 ± 20 kg, age 52 ± 9 years, range 39–67 years) with OSAS were studied prospectively. They were advised to follow a 2·51–3·35 MJ (600–800 kcal) diet daily for a 3-month period. In the beginning of the study, the patients underwent nocturnal sleep studies, autonomic function tests and 24-h electrocardiograph (ECG) recording. In addition, 15 age-matched, normal-weight subjects were studied. They underwent the Valsalva test, the deep-breathing test and assessment of heart rate variability at rest. The sleep studies and autonomic function tests were repeated after the weight loss period. There was a significant reduction in weight (114 ± 20 kg to 105 ± 21 kg, P<0·001), the weight loss being 9·2 ± 4·0 kg (range 2·3–19·5 kg). This was associated with a significant improvement in the oxygen desaturation index (ODI4) during sleep (31 ± 20–19 ±18, P<0·001). Before the weight loss the OSAS patients had significantly higher blood pressure (150 ± 18 vs. 134 ± 20, P<0·05, for systolic blood pressure, 98 ± 10 vs. 85 ± 13, P<0·05, for diastolic blood pressure) and heart rate (67 ± 10 beats min^?1 vs. 60 ± 13, P<0·05) at rest than the control group. They had also lower baroreflex sensitivity (4·7 ± 2·8 ms mmHg^?1 vs. 10·8 ± 7·1 ms mmHg^?1, P<0·01). During the weight reduction, the blood pressure declined significantly, and the baroreflex sensitivity increased by 49%. In conclusion, our experience shows that weight loss with VLCD is an effective treatment for OSAS. Weight loss improved significantly sleep apnoea and had favourable effects on blood pressure and baroreflex sensitivity that may have prognostic implications.     

Predictors of health-related quality of life in patients with obstructive sleep apnoea

Title. Predictors of health-related quality of life in patients with obstructive sleep apnoea Aim. This paper is a report of a study to identify the common symptoms and demographic and physiological factors of obstructive sleep apnoea that are predictive of health-related quality of life in a Chinese population. Background. Health-related quality of life impairment in obstructive sleep apnoea is an increasingly important consideration, but little is known about the factors that influence quality of life in this population. Method. A total of 108 Chinese patients with newly diagnosed obstructive sleep apnoea were recruited in 2003 and assessed for health-related quality of life, daytime sleepiness, depression and anxiety. Associations between symptoms, demographic and physiological factors and quality of life were examined by Pearson linear correlation. Hierarchical multiple regression were used to determine predictors of overall quality of life and its dimensions. Results. Forty-six patients (42·6%) had depressed mood and 21 (19·4%) were anxious. Fifty-nine (54·6%) were hypersomnolent. The severity of symptoms of sleepiness, depression, and anxiety was statistically significantly inversely correlated with each domain and the total score for health-related quality of life. No statistically significant correlation was observed between disease severity and quality of life. Controlling for age and gender, anxiety and sleepiness predicted 45·2% of the variance of overall quality of life (R² = 0·452, P < 0·001). Anxiety was the strongest predictor of overall and each domain of health-related quality of life. Conclusion. Assessment of mood in patients with obstructive sleep apnoea should be an essential part of nursing practice. Comprehensive evaluation of symptoms, especially mood disturbance, is important for improving quality of life for these patients.     

Non-pharmacological interventions for breathlessness management in patients with lung cancer: a systematic review

The aim is to review the published scientific literature for studies evaluating non-pharmacological interventions for breathlessness management in patients with lung cancer. The following selection criteria were used to systematically search the literature: studies were to be published research or systematic reviews; they were to be published in English and from 1990 to 2007; the targeted populations were adult patients with dyspnoea/breathlessness associated with lung cancer; and the study reported on the outcomes from use of non-pharmacological strategies for breathlessness. This review retrieved five studies that met all inclusion criteria. All the studies reported the benefits of non-pharmacological interventions in improving breathlessness regardless of differences in clinical contexts, components of programmes and methods for delivery. Analysis of the available evidence suggests that tailored instructions delivered by nurses with sufficient training and supervision may have some benefits over other delivery approaches. Based on the results, non-pharmacological interventions are recommended as effective adjunctive strategies in managing breathlessness for patients with lung cancer. In order to refine such interventions, future research should seek to explore the core components of such approaches that are critical to achieving optimal outcomes, the contexts in which the interventions are most effective, and to evaluate the relative benefits of different methods for delivering such interventions.     

Autoantibodies against oxidised low-density lipoprotein in patients with obstructive sleep apnoea.

Autoantibodies against oxidised low-density lipoprotein (OxLDL-Abs) have been proposed to be an indicator of endothelial dysfunction and a novel tool for finding individuals with a high cardiovascular risk. In a cross-sectional study, OxLDL-Abs were measured in 297 patients with obstructive sleep apnoea (OSA) and 54 controls using an enzyme-linked immunosorbent assay. The autoantibodies were increased in patients with OSA when compared to controls (age, body mass index (BMI) and gender adjusted, p = 0.001). However, within the OSA patients, OxLDL-Abs were not related to smoking, hypertension or BMI, and there was a weak negative correlation (r = -0.16, P = 0.007) between age and levels of OxLDL-Abs. In conclusion, at present the measurement OxLDL-Abs still remains a method for basic research and is not applicable for screening of at-risk patients with OSA.     

Factors associated with undiagnosed obstructive sleep apnoea in hypertensive primary care patients

Objective

In hypertensive primary care patients below 65 years of age, (i) to describe the occurrence of undiagnosed obstructive sleep apnoea (OSA), and (ii) to identify the determinants of moderate/severe OSA.

Design

Cross-sectional.

Setting

Four primary care health centres in Sweden.

Patients

411 consecutive patients (52% women), mean age 57.9 years (SD 5.9 years), with diagnosed and treated hypertension (BP >140/90).

Main outcome measures

Occurrence of OSA as measured by the apnoea hypopnoea index (AHI).

Results

Mild (AHI 5–14.9/h) and moderate/severe (AHI > 15/h) OSA were seen among 29% and 30% of the patients, respectively. Comparing those without OSA with those with mild or moderate/severe OSA, no differences were found in blood pressure, pharmacological treatment (anti-hypertensive, anti-depressive, and hypnotics), sleep, insomnia symptoms, daytime sleepiness, or depressive symptoms. Obesity (BMI > 30 kg/m2) was seen in 30% and 68% of the patients with mild and moderate/severe OSA, respectively. Male gender, BMI > 30 kg/m2, snoring, witnessed apnoeas, and sleep duration >8 hours were determinants of obstructive sleep apnoea.

Conclusion

Previously undiagnosed OSA is common among patients with hypertension in primary care. Obesity, snoring, witnessed apnoeas, long sleep duration, and male gender were the best predictors of OSA, even in the absence of daytime sleepiness and depressive symptoms.Key Words: Depression, hypertension, obstructive sleep apnoea, sleep, sleep disordered breathing, snoringCurrent awareness:

• Obstructive sleep apnoea has been linked to hypertension in sleep clinic populations, but there is a lack of knowledge regarding the occurrence in Swedish hypertensive primary care patients.

Main statements:

• Undiagnosed mild and moderate/severe obstructive sleep apnoea was seen among 29% and 30% of patients, respectively.
• Comparing subjects with mild or moderate/severe obstructive sleep apnoea with those without, no differences were found in blood pressure, self-rated sleep duration, insomnia, daytime sleepiness, or depressive symptoms.
• Male gender, BMI > 30 kg/m00B2, snoring, witnessed apnoeas, and sleep duration >8 hours were determinants of moderate/severe obstructive sleep apnoea in hypertensive primary care patients.

     

Disorders of glucose metabolism and insulin resistance in patients with obstructive sleep apnoea syndrome

Objective: Insulin resistance (IR) and disorders of glucose metabolism (DGM) are risk factors for cardiovascular diseases. There are different reasons for development of DGM in patients with obstructive sleep apnoea syndrome (OSAS) and this association is controversial. We investigated the frequency of DGM and IR in patients with OSAS and determining factors for these disorders. Method: One hundred and twelve untreated patients with OSAS and 19 non‐apnoeic snoring subjects upon polysomnography were included in this study. Oral glucose tolerance test (OGTT) was performed in all subjects who had fasting blood glucose < 125 mg/dl. IR method was analysed using homeostasis assessment model (HOMA‐IR). Diabetes mellitus (DM), impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) were defined according to values of OGTT. DGM was defined as having one of the diagnoses of DM, IGT or IFG. Subjective sleepiness of all subjects was assessed with Epworth Sleepiness Scale (ESS). Excessive daytime sleepiness (EDS) was described as ESS score ≥ 10. Results: Fasting glucose and the rate of DGM in patients with OSAS were higher than in non‐apnoeic snoring subjects. DGM were shown in % 15.7 of non‐apnoeic snoring subjects, 29.6% of mild sleep apnoea, 50% of moderate sleep apnoea and 61.8% of severe sleep apnoea. The rate of DGM in patients with moderate and severe OSAS was higher than in non‐apnoeic snoring subjects and in patients with severe OSAS higher than in patients with mild OSAS. DGM are associated with body mass index (BMI), severity of OSAS, arousal index and EDS. In addition, IR is associated with apnoea hypopnoea index, BMI, arousal index and ESS score. Conclusion: Obstructive sleep apnoea syndrome is associated with high frequency of DGM. In addition, the progression of disease from simple snoring and mild OSAS to severe OSAS increases the rate of DGM. Thus, DGM especially in patients with severe OSAS should be examined in regular periods.     

阻塞性睡眠呼吸暂停综合征与颈动脉粥样硬化相关性的系统评价

目的系统评价阻塞性睡眠呼吸暂停综合征(obstructive sleep apnea syndrome,OSAS)与颈动脉粥样硬化疾病的相关性。方法计算机检索PubMed、EMbase、CNKI、WanFang Data、CBM和VIP数据库,搜集OSAS与颈动脉粥样硬化疾病和颈动脉内膜中层厚度(carotid intima–media thickness,CIMT)相关性的研究,检索时限均从建库至2021年8月10日。由2位评价员独立筛选文献、提取资料并评价纳入研究的偏倚风险后,采用RevMan 5.3软件和Stata 16.0软件进行Meta分析。结果共纳入32个研究,包括2915例患者。Meta分析结果显示:与对照组相比,OSAS患者颈动脉粥样硬化斑块发生率更高[OR=5.56,95%CI(0.27,8.38),P<0.00001]。亚组分析结果发现,男性[OR=5.38,95%CI(2.79,10.38),P<0.00001]、轻中度OSAS[OR=3.9,95%CI(1.66,9.15),P=0.002]、重度OSAS[OR=19.86,95%CI(6.49,60.82),P<0.00001]患者颈动脉粥样硬化斑块发生风险均高;此外,OSAS组与对照组相比CIMT明显升高[SMD=1.24,95%CI(0.97,1.51),P<0.00001]。OSAS患者AHI和CIMT间呈正相关[r=0.52,95%CI(0.44,0.60),P<0.0001],CIMT随OSAS严重程度的增加而升高。结论OSAS患者颈动脉粥样硬化斑块发生率更高,与CIMT呈正相关,且CIMT会随AHI的升高而升高。受纳入研究数量和质量限制,上述结论尚需开展更多高质量研究予以验证。