P-wave duration and dispersion in patients with obstructive sleep apnea

AimP-wave dispersion (Pd) has been reported to be associated with inhomogeneous and discontinuous propagation of sinus impulses. The purpose of this study was to investigate Pd in patients with obstructive sleep apnea (OSA) and to determine its relationship with severity of the disease.MethodsThe study population included 67 patients referred to sleep laboratory. The Apnea–Hypopnea Index (AHI) was defined as the number of apneas and hypopneas per hour of sleep. Of the sixty-seven patients, 48 had AHI?5 and were diagnosed as OSA. Nineteen of the patients had AHI < 5 and were diagnosed as OSA (?) (Group 1), 32 of the patients had AHI between 5–30 (mild and moderate, group 2), 16 of the patients had AHI > 30 (severe, group 3). The P-wave duration was calculated in all leads of the surface electrocardiogram. The difference between the maximum (Pmax) and minimum P (Pmin) wave duration was calculated and was defined as the P-wave dispersion (Pd). Echocardiographic examination was also performed.ResultsPmax was longer in group 3 compared to group 2 and group 1 (p = 0.002, p < 0.001 respectively). Pmax was longer in group 2 compared to group 1 (s < 0.001). Pd was greater in group 3 compared to group 2 and group 1 (p < 0.001 for both comparison). Pd was greater in group 2 compared to group 1 (p < 0.001). Pmin did not differ between the groups. In patients with OSA, Pd was positively correlated with AHI (r = 0.56, p < 0.001), BMI (r = 0.43, p = 0.03), and mitral early diastolic to late diastolic velocity (E/A) ratio (r = 0.37, p = 0.01). Multiple linear regression analysis showed that only AHI was independently associated with Pd (β = 0.39, p = 0.02).ConclusionPd was found to be greater in patients with OSA than patients without OSA and to be associated with severity of the disease.     

阻塞性睡眠呼吸暂停低通气综合征与P波离散度关系的研究

目的探讨P波离散度与OSAHS严重程度之间的关系,分析OSAHS导致其发生变化的可能机制。方法通过12导联心电图机,对118名研究对象就P波离散(PWD)定量测量,并结合多导睡眠监测,比较不同严重程度的OSAHS患者PWD的水平差异。结果 OSAHS组较正常对照组PWD有明显的升高,(44.22±6.74 ms VS 35.81±4.79 ms,P<0.001)。而且不同程度OSAHS三组PWD两两比较,PWD与AHI指数成正相关(r=0.698,P<0.001)。最低氧饱和度与PWD呈负相关(r=-0.563,P<0.001)。结论 PWD的大小与OSASH患者的严重程度相关。PWD可作为一项OSASH患者初筛、评价指标,同时也可预测未来发生房颤的风险。     

The impact of sleep duration in obstructive sleep apnea patients

Purpose

Obstructive sleep apnea (OSA) is a risk factor for cardiovascular disease. Strong associations have been reported among sleep duration, hypertension, obesity, and cardiovascular mortality. The authors hypothesize that sleep duration may play a role in OSA severity. The aim of this study is to analyze sleep duration in OSA patients.

Methods

Patients who underwent overnight polysomnography were consecutively selected from the Sleep Clinic of Universidade Federal de São Paulo database between March 2009 and December 2010. All subjects were asked to come to the Sleep Clinic at 8:00 a.m. for a clinical evaluation and actigraphy. Anthropometric parameters such as weight, height, hip circumference, abdominal circumference, and neck circumference were also measured.

Results

One hundred thirty-three patients were divided into four groups based on total sleep time, sleep efficiency, sleep latency, and wake after sleep onset: very short sleepers (n?=?11), short sleepers (n?=?21), intermediate sleepers (n?=?56), and sufficient sleepers (n?=?45). Apnea–hypopnea index (AHI) was higher in very short sleepers (50.18?±?30.86 events/h) compared with intermediate sleepers (20.36?±?14.68 events/h; p?=?0.007) and sufficient sleepers (23.21?±?20.45 events/h; p?=?0.02). Minimal and mean arterial oxygen saturation and time spent below 90 % oxygen saturation exhibited worse values in very short sleepers. After adjustment for gender, age, AHI, and body mass index, mean oxygen saturation was significantly associated to total sleep time (p?=?0.01).

Conclusions

In conclusion, the present study suggests that sleep duration may be associated to low mean oxygen saturation in OSA patients.     

Apnea duration and hypoxemia during REM sleep in patients with obstructive sleep apnea

Nocturnal sleep studies of 12 patients with obstructive sleep apnea and a matched control group of 12 subjects without the sleep apnea syndrome were analyzed to compare arterial oxyhemoglobin saturation (SaO2) during REM and non-REM sleep. Mean percentage of total sleep time spent in REM sleep was not significantly different in patients with obstructive sleep apnea and in subjects without significant apnea (14.2 +/- SEM 2.2 percent in patients vs 12.0 +/- 2.2 percent in nonapnea subjects). Apneas were longer during REM than non-REM sleep in all 12 patients (p less than 0.01). Oxyhemoglobin desaturations were more frequent during REM than non-REM sleep in both apnea patients and the control subjects. In addition, there was a greater mean fall in SaO2 per desaturation episode in both the apnea patients and non-apnea subjects. We conclude: 1) sleep apneas are longer during REM sleep than non-REM sleep in patients with obstructive sleep apnea; 2) hypoxemia is greater during REM sleep than non-REM sleep in subjects with and without the sleep apnea syndrome.     

Signal-averaged P wave area increases during respiratory events in patients with paroxysmal atrial fibrillation and obstructive sleep apnea

Sleep and Breathing - P wave characteristics change during simulated apneic events in individuals with atrial fibrillation (AF). This study sought to assess whether similar changes occur during...     

A fatty meal aggravates apnea and increases sleep in patients with obstructive sleep apnea

Purpose

The purpose of this study was to investigate the role of a fatty meal before bedtime, on sleep characteristics and blood pressure in patients with obstructive sleep apnea (OSA).

Methods

Recently diagnosed, by full polysomnography (PSG), patients with OSA (n?=?19) were included. These underwent PSG for additional two consecutive nights. Two hours before the PSG examination, a ham and cheese sandwich of 360 kcal was served to all patients, at first night, while a fatty meal of 1,800 kcal was served before the second PSG examination. Comparisons were performed between the last two examinations in terms of PSG data and morning and night blood pressure measurements.

Results

After the fatty meal, a significant increase was observed in total sleep time (p?=?0.026) in the Apnea–Hypopnea Index (AHI) (p?=?0.015), as well as in the absolute number of obstructive and central apneas (p?=?0.032 and p?=?0.042, respectively) compared to the previous night. Conversely, distribution of sleep stages and indices of nocturnal hypoxia (average and minimum SpO₂ and sleep time with SpO₂?<?90 %) did not change significantly. Likewise, no significant change was observed in blood pressure measurements.

Conclusions

Fatty meal intake before sleep can increase AHI in OSA patients, although it does not affect sleep architecture or indices of hypoxia.     

Craniofacial obesity in patients with obstructive sleep apnea

Introduction  Obstructive sleep apnea (OSA) and obesity are serious, widespread public health issues. Objective  To localize and quantify geometric morphometric differences in facial soft tissue morphology in adults with and without OSA. Materials and methods  Eighty adult Malays, consisting of 40 patients with OSA and 40 non-OSA controls, were studied. Both groups were evaluated by the attending physician and through ambulatory sleep studies. 3-D stereophotogrammetry was used to capture facial soft tissues of both groups. The 3-D mean OSA and control facial configurations were computed and subjected to principal components analysis (PCA) and finite-element morphometry (FEM). Results  The body mass index was significantly greater for the OSA group (32.3 kg/m² compared to 24.8 kg/m², p < 0.001). The neck circumference was greater for the OSA group (42.7 cm compared to 37.1 cm, p < 0.001). Using PCA, significant differences were found in facial shape between the two groups using the first two principal components, which accounted for 50% of the total shape change (p < 0.05). Using FEM, these differences were localized in the bucco-submandibular regions of the face predominantly, indicating an increase in volume of 7–22% (p < 0.05) for the OSA group. Conclusion  Craniofacial obesity in the bucco-submandibular regions is associated with OSA and may provide valuable screening information for the identification of patients with undiagnosed OSA.     

Renal function in patients with obstructive sleep apnea

Sleep and Breathing -     

Effect of mean apnea-hypopnea duration in patients with obstructive sleep apnea on clinical and polysomnography parameter

Sleep and Breathing - Apnea-hypopnea index is the number of apnea-hypopnea events observed during polysomnography within an hour. Mean apnea-hypopnea duration is the mean duration of all apneas and...     

Relationship between the severity of obstructive sleep apnea and impaired glucose metabolism in patients with obstructive sleep apnea

BACKGROUND: The relationship between the severity of obstructive sleep apnea (OSA) and impaired glucose metabolism (IGM) has not yet been fully elucidated in patients with OSA. Accordingly, we sought to clarify this relationship in Japanese patients with OSA. METHODS: The study population consisted of 129 Japanese patients with OSA (apnea-hypopnea index [AHI] >/=5). A 75-g oral glucose tolerance test was performed in all patients who had not been diagnosed as diabetes mellitus (DM). IGM was defined as either diabetes mellitus (DM) or impaired glucose tolerance (IGT). RESULTS: IGM was observed in 78 (60.5%) patients: DM in 39 (30.2%) and IGT in 39 (30.2%). The frequency of IGM was significantly different among patients with AHI >/=30, those with 15 /=5), and the prevalence of IGM increased according to the severity of OSA. Furthermore, the AHI was independently associated with IGM, thus suggesting that OSA may contribute to the development of IGM.     

Personality profiles in patients with obstructive sleep apnea

Objective

The Minnesota Multiphasic Personality Inventory (MMPI) responses between snorers and obstructive sleep apnea (OSA) may be different. Thus, we compared the MMPI responses between snorers and OSA.

Design

A clinical-based cross-sectional survey.

Participants

This is a survey of 94 treatment-naive sleep-disordered breathing (SDB) subjects.

Method

Clinical information, body mass index (BMI), 36-item Short Form Health Survey, the Turkish version of the MMPI, Epworth sleepiness scale (ESS), fatigue scale, attention-deficit scale, and polysomnography were collected. All patients with OSA and snorers was accepted as individuals with SDB (AHI?>?0 events/h). The threshold of five apnea and hypopnea per hour of sleep was chosen to define both OSA and snorers. Disability profile is consisting of four or more MMPI clinical scale elevations.

Results

OSA patients compared to snorers have significantly higher absolute scores on hypochondriasis (Hs) (65.0?±?12.0 vs 58.4?±?7.9, p?=?0.01, respectively). OSA patients compared to snorers have significantly higher rate of clinical elevation on both psychopathic deviance (13.0 vs 0?%, p?=?0.03, respectively) and Hs (26.1 vs 3.3?%, p?=?0.01, respectively). People with disability profile has lower the quality of life, a higher score for inattention, a higher fatigue scores, and higher sleepiness scores. The quality of life and attention deficit and daytime sleepiness scores were associated with total MMPI absolute score in individuals with SDB in bivariate analyses.

Conclusion

Present study indicated that patients with OSAS compared to snorers displayed significantly more hyopchondriasis and psychopathic deviance personality characteristics. The daytime functions in individuals with sleep-disordered breathing may be influenced by the severity of psychopathology.     

The predictive value of Holter monitoring in the risk of obstructive sleep apnea

BackgroundPatients with obstructive sleep apnea (OSA) often present with cardiovascular symptoms. Holter monitors were reported to predict sleep apnea, though were rarely used in everyday clinical practice. In this study, by comparing Holter monitoring to polysomnography (PSG), we try to find out an operable way for clinicians to use Holter to predict OSA risk.MethodsPatients (n=63) suspected of OSA underwent Holter monitoring with concurrent PSG at a sleep center. Respiration and heart rate variability (HRV) indices were calculated from the Holter and compared with PSG indices.ResultsThe sensitivity of the Holter-derived respiratory waveform for OSA was 90.0%, and the specificity was 82.6%. The time domain indices including standard deviation of all NN intervals during 24 hours, mean of standard deviation of the averages of NN intervals in all 5-minute segments, square root of the mean squared differences of successive NN intervals, percentage of beat-to-beat NN interval differences that were more than 50 milliseconds, and the frequency domain index of high frequency decreased in participants with OSA and correlated with the PSG derived indices including apnea-hypopnea index (AHI), oxygen reduction index (ODI) and nadir SaO₂. Logistic regression showed that standard deviation of all NN intervals during 24 hours and gender could predict the risk of OSA (P<0.001), with a sensitivity for diagnosing moderate to severe OSA of 87.5% and could accurately distinguish the risk of OSA in 77.8% of patients. Males with standard deviation of all NN intervals during 24 hours ≤177 ms or females with standard deviation of all NN intervals during 24 hours ≤80.9 ms were considered to be at high risk for OSA.ConclusionsCommercial and common parameters from Holter monitoring could predict the risk of OSA with high sensitivity. Therefore, the risk of OSA may be assessed using the Holter examination to improve the diagnosis and treatment rate of OSA.     

Prevalence of concomitant sleep disorders in patients with obstructive sleep apnea

We determined the prevalence of concomitant sleep disorders in patients with a primary diagnosis of obstructive sleep apnea (OSA). We retrospectively analyzed 643 patients, aged 18, with a primary diagnosis of OSA, evaluated by sleep specialists, in whom clinical and polysomnographic data were derived using standardized techniques by reviewing data from a standardized database and clinical charts. Concomitant sleep disorders were listed according to the International Classification of Sleep Disorders (American Academy of Sleep Medicine, 2000). The mean age was 48.5±13.5 years and 55% were male. Racial distributions were African–Americans 51.8% and Caucasian 47%. Indices of disordered breathing were respiratory disturbance index 32.4±30.4/h sleep and time <90% O₂ saturation 44.5±81.6 min. Thirty-one percent of patients had a concomitant sleep disorder. The most common were inadequate sleep hygiene (14.5%) and periodic limb movement disorder (PLMD, 8.1%). Of patients with other sleep disorders, 66.8% had treatment initiated for these disorders. Predictors of inadequate sleep hygiene (logistic regression) were: age (each decade OR=0.678, P=0.000000), gender (for M, OR=0.536), and the presence of at least one other major system disorder (OR=2.123, P=0.0015). Predictors of PLMD were: age (each decade OR=0.794, P=0.0005), gender (for M, OR=0.433, P=0.004), and total sleep time (for each 10 min, OR=0.972, P=0.0013). We conclude that approximately one third of patients with sleep apnea have another identifiable sleep disorder, usually requiring treatment. This suggests that practitioners evaluating and treating sleep apnea ought to be prepared to deal with other sleep disorders as well.     

Measurement of dyspnea in patients with obstructive sleep apnea

Purpose

Patients with obstructive sleep apnea (OSA) frequently complain of exertional dyspnea. We aimed to assess its related factors and the significance of its measurement in OSA.

Methods

We evaluated 301 subjects with suspected OSA for dyspnea during activities of daily living using the Medical Research Council (MRC) scale. We analyzed the relationships between MRC grades and various subjective and objective indices. Further, the relationship of disease severity based on the apnea/hypopnea index (AHI) with these indices was examined. Results were compared between those obtained using MRC grades and the AHI.

Results

Of 301 subjects, 265 were diagnosed with OSA. Their MRC scores were worse than in non-OSA patients. Among OSA patients, 125 had MRC grade 1 (mild), 121 had MRC grade 2 (moderate), and 19 had MRC grade 3 or more (severe) dyspnea. Various measurements differed significantly between groups categorized according to the MRC scale although determinants between mild and moderate groups and between moderate and severe groups differed. AHI categorizations were not significantly related to patient-reported measurements such as the Medical Outcomes Study 36-item short form, Pittsburgh Sleep Quality Index, and Hospital Anxiety and Depression Scale scores, unlike categorization based on the MRC scale.

Conclusions

Dyspnea is an important outcome in OSA although dyspnea in OSA patients is unrelated to the sleep disorder per se. Measurement of dyspnea in patients with OSA might provide further insights into the health of these patients and clinical manifestations of this disease.     

Perioperative treatment of patients with obstructive sleep apnea

PURPOSE OF REVIEW: Obstructive sleep apnea is a common disorder. Despite reports of its role as a risk factor for postoperative morbidity and mortality, only a few investigators have examined the optimal treatment of patients during this vulnerable period. Recognition of obstructive sleep apnea during conscious sedation or in the perioperative period is important to prevent the occurrence of adverse outcomes. This review discusses the influence of sedative, anesthetic, and analgesic agents and other factors during the perioperative period on patients with obstructive sleep apnea. The aim of this article is to emphasize the importance of recognizing and appropriately treating surgical patients with obstructive sleep apnea. RECENT FINDINGS: Sedative, analgesic, and anesthetic agents used perioperatively play a major role in the development of sleep-disordered breathing during the postoperative period. Postoperative apneic episodes frequently occur even after surgery remote from the upper airway. Sleep apnea predisposes patients to a greater than normal risk for postsurgical complications. Adequate screening of patients preoperatively and initiation of continuous positive airway pressure therapy perioperatively could prevent serious complications, including hypoxemia, arrhythmias, myocardial infarction, and respiratory arrest. SUMMARY: Obstructive sleep apnea places a significant proportion of surgical patients at increased risk of perioperative complications. Obstructive sleep apnea can be induced, unmasked, or exacerbated by the effects of sedative, analgesic, and anesthetic agents regardless of the site of surgery. The role of sleep apnea as a risk factor for development of postoperative complications needs greater emphasis. Increased awareness of the risk posed by an obstructed upper airway and appropriate management are important to optimize the perioperative care of patients with obstructive sleep apnea.     

胺碘酮与缬沙坦对阵发性心房颤动患者P波离散度的影响的研究

目的 评价胺碘酮与缬沙坦对阵发性心房颤动（PAF）患者P波离散度和最大P波时限（Pmax）的影响。方法 96例阵发性心房颤动的患者被随机分成胺碘酮加缬沙坦组32例，胺碘酮组31例，缬沙坦组33例。对照组34例为正常健康人，观察药物治疗3个月前后心电图Pmax和Pdis的变化。结果 阵发性心房颤动患者Pmax、Pdis治疗前均与对照组比有显著性差异（P〈0．01），药物治疗3个月后，胺碘酮治疗能改善Pmax和Pdis，但胺碘酮加缬沙坦组改善Pmax和Pdis更显著（P〈0．05），缬沙坦组则与治疗前相比无显著性差异（P〉0．05）。结论 PAF患者的Pmax和Pdis与对照组相比有显著性差异，胺碘酮加缬沙坦治疗能显著改善PAF患者的Pmax和Pdis。