Driving performance and automobile accidents in patients with sleep apnea.

Patients with untreated obstructive sleep apnea have poorer driving performance than patients without sleep apnea. This poor driving has been demonstrated by studies on a wide variety of driving simulators. Patients with sleep apnea show a significant improvement in driving performance after successful treatment of their apnea with nasal CPAP. After treatment with CPAP, their driving performance is similar to control subjects. Several studies show that patients with untreated sleep apnea are poor drivers and have two to three times more auto accidents than other drivers. These studies reveal that almost one quarter of these patients report frequently falling asleep while driving. Patients with severe sleep apnea or those who perform poorly on driving simulators may be at highest risk of auto accidents. Automobile accidents involving patients with sleep apnea may lead to severe injury or death. Patients, individual physicians, and the medical profession have responsibilities to help prevent these accidents. Finally, more study is needed to improve patient care, protect drivers, and formulate a fair and rational policy concerning drivers with sleep apnea.     

Central sleep apnea and complex sleep apnea in patients with epilepsy

Purpose

We sought to examine the prevalence of central sleep apnea (CSA) and complex sleep apnea (CompSA) in patients with epilepsy and to examine their clinical profile, with respect to epilepsy type, etiology, medication use, and EEG abnormalities.

Methods

We undertook a retrospective analysis of 719 consecutive patients with epilepsy who underwent polysomnography (PSG) at our institution between 2004 and 2011. Of the 458 patients with complete data, we excluded 42 patients with congestive heart failure or left ventricular ejection fraction <40 %. Comparison of clinical and PSG variables between the three groups were conducted with Fisher exact test and analysis of variance.

Results

Out of 416 patients tested, 315 (75 %) had obstructive sleep apnea (OSA), 16 (3.7 %) had CSA, 33 (7.9 %) had CompSA. There were more males in the CSA and CompSA groups than in the OSA group (81.2, 81.8, and 59.6 %, respectively, p?=?0.04). Focal seizures were more prevalent in patients with CSA than in patients OSA or CompSA (62.5, 265, and 21.1 %, respectively, p?=?0.02).

Conclusion

About 11 % of epilepsy patients have sleep-breathing disorders with central apneas, which is not higher than that in a general population. These data should be expanded with future research investigating the role of interictal, ictal, and postictal central apneas in epileptogenesis and epilepsy.     

Caffeine intake is independently associated with neuropsychological performance in patients with obstructive sleep apnea

In healthy individuals, caffeine intake may improve performance on cognitive tests. Obstructive sleep apnea (OSA) is a disorder that has been associated with impaired cognitive function. In this study, we investigated whether increased caffeine intake in untreated patients with OSA is linked to better cognitive performance. Forty-five untreated OSA patients underwent baseline polysomnography after completing a survey of 24-h caffeine intake. Participants completed a battery of neuropsychological tests, then demographically corrected T scores and a global deficit score (GDS) were calculated on these tests. Partial correlation analysis was performed to compare daily caffeine intake with GDS, after controlling for body mass index (BMI) and sleep apnea severity. Analysis of covariance was done to examine differences in daily caffeine intake between cognitively impaired (GDS >/= 0.5) and non-impaired (GDS < 0.5) individuals. Seven out of the 45 subjects met the criteria (GDS >/= 0.5) for cognitive impairment. There was a significant inverse association between caffeine intake and the GDS, both when controlling for BMI (r = -0.331, p = 0.04) and when controlling for BMI and apnea severity (r = -0.500, p = 0.002); those with less impairment consumed more caffeine. Analysis of covariance demonstrated that cognitively impaired individuals consumed one-sixth as much caffeine as non-impaired individuals (p < 0.05). In patients with moderately severe OSA, higher average daily caffeine intake was associated with less cognitive impairment.     

Factors impairing daytime performance in patients with sleep apnea/hypopnea syndrome.

Patients with sleep apnea/hypopnea syndrome commonly demonstrate impaired daytime performance. In a prospective study, 29 patients with sleep apnea/hypopnea syndrome were assessed polysomnographically to determine the relationship of cognitive performance and daytime sleepiness with sleep disruption, hypoxemia, and mood. Deterioration of cognitive performance correlated significantly with increasing severity of nocturnal breathing irregularity, magnitude of nocturnal hypoxemia, and extent of sleep disruption. Multiple regression analysis identified frequency of apneas plus hypopneas and of arousal and the extent of nocturnal hypoxemia as the variables most strongly associated with cognitive deficits. Anxiety and depression also contributed to this impairment. Objective daytime sleepiness was not significantly associated with nocturnal variables. This study showed that the frequency of breathing irregularities and the extent of both sleep disruption and nocturnal hypoxemia are important in determining daytime function in patients with sleep apnea/hypopnea syndrome. All of these factors should be considered when deciding which patients require treatment.     

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.     

Do patients with sleep apnea die in their sleep?

Patients with sleep apnea syndrome (SAS) show cardiac dysrhythmias in association with cyclical nocturnal hypoxemia; are they at risk of dying during sleep? To assess this claim, we reviewed the clinical course of 91 patients with polysomnographically documented SAS between July 1978 and June 1986. A control group was comprised of 35 patients who were referred with symptoms suggestive of SAS but had negative sleep studies. Follow-up was obtained by survey questionnaire. Nine of 91 SAS and four of 35 control patients had died by completion of the study. There were no statistically significant differences in mortality between the two groups. None of the SAS patients died in their sleep, but they reported a higher incidence of disability and vehicular mishaps than did control subjects. The findings in this study do not support the hypothesis that SAS patients are at increased risk of dying in their sleep.     

Comparison of cognitive performance among different age groups in patients with obstructive sleep apnea

The aim of this study was to evaluate the effect of obstructive sleep apnea syndrome on the cognitive performance of young and middle-aged patients. Patients were divided into two groups, one consisting of 30 patients less than 50 years of age and the other consisting of 28 patients 50 years and over. Normal subjects were similarly divided into two groups, composed of 17 younger and 24 older controls. Patients and controls were examined with all-night polysomnography and subsequently underwent cognitive testing via attention–alertness tests. Comparing young to middle-aged patients, there were statistically significant differences in cognitive performance, especially in attention tests. Younger patients’ cognitive performance was similar to their age-matched controls, while middle-aged patients showed cognitive decline in comparison with their age-matched controls. Although we studied only two age groups using 50 years of age as a cut-off, we could demonstrate that cognitive deterioration of untreated sleep apnea patients is age dependent, and several factors may contribute to this effect including brain hypoxia, sleep fragmentation, or comorbidities. Aging patients with sleep apnea demonstrate cognitive decline, while younger patients with the same disease severity are (somehow) able to compensate for this effect.     

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 -     

睡眠呼吸暂停低通气综合征患者的夜间心电图ST段下降

目的确定睡眠呼吸暂停是否可导致由心电图ST段下降所反映的夜间心肌缺血,以及这种心肌缺血的严重程度是否可通过持续气道内正压通气(CPAP)治疗所减轻.方法对32名无冠心病病史的中重度睡眠呼吸暂停综合征患者行整夜的多导睡眠图研究,同时行三导联的动态心电图(Holter)监测,全部病例接受一夜的CPAP治疗.ST段下降定义为相对于基线下降至少1 mm并持续至少1 min.计算ST段下降指数(min/h),即将ST段下降的时间与整个睡眠时间相比较.结果11例(34%)的患者睡眠中出现ST段下降.当患者没有接受CPAP治疗时,ST段下降时的呼吸暂停指数和觉醒指数明显高于ST段处于等电位状态时,而血氧饱和度无明显差异.全部ST段下降者经CPAP治疗后,其ST段下降的时间明显减少[(33.4±19.7)min/h vs(10.2±12.9)min/h,P＜0.05],与之相关联的呼吸暂停/低通气指数、觉醒指数及血氧饱和度＜90%的时间占睡眠时间的百分比均明显下降,其值分别为(61.8±23.4)/h vs(8.1±6.6)/h,(50.2±18.3)/h vs(7.6±5.3)/h和(52.6±21.7)%vs(12.9±14.7)%(P＜0.05).结论中重度睡眠呼吸暂停综合征患者睡眠中的ST段下降相对常见,CPAP治疗可以明显地减少ST段下降的时间.此类患者的ST段下降可能反映了真实存在的心肌缺血,也可能反映了与反复发生的睡眠呼吸暂停相关的非缺血性改变.     

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.     

Undiagnosed sleep apnea in patients with essential hypertension

The prevalence of sleep apnea was studied in 46 middle- and older-aged men with "essential hypertension." Thirty-four age- and weight-similar normotensive men were also studied. Fourteen hypertensive men and three controls had sleep apnea syndrome, as defined as greater than ten apneas per hour of sleep. Hypertensive men with apnea tended to be more overweight and slightly older than the hypertensive men without apnea, but differences were not statistically significant. Individual men with apnea could not be distinguished by their answers on a questionnaire that elicited symptoms related to apnea. Seven hypertensive men with apnea were treated with protriptyline and one with uvulopalatopharyngoplasty, and apnea index (apneas per hour) decreased by 77% from pretreatment levels while mean blood pressure decreased from 149/95 mm Hg to 139/90 mm Hg. Undiagnosed sleep apnea syndrome may be associated with systemic hypertension in many middle- and older-aged men. In some, sleep apnea syndrome could be the cause of hypertension, and in others it may contribute to hypertension of another cause.     

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.     

阻塞性睡眠呼吸暂停患者残余嗜睡与中枢性睡眠呼吸暂停事件的相关性

目的 探讨阻塞性睡眠呼吸暂停综合征(obstructive sleep apnea syndrome,OSAS)患者连续气道正压通气(continuous positive airway pressure,CPAP)治疗后残余嗜睡与中枢性睡眠呼吸暂停(central sleep apnea,CSA)事件的相关性以及匹配伺服通气(adaptive Bervo-ventilation,ASV)对CSA相关残余嗜睡的影响. 方法 选择正规使用CPAP治疗且排除其他嗜睡相关疾病的中、重度OSAS患者50例,分为残余嗜睡组(26例)和无残余嗜睡的对照组(24例).2组患者均先后接受自动CPAP治疗1个月和ASV治疗1周.分别比较2组患者治疗前、自动CPAP治疗时及ASV治疗时睡眠期的中枢性睡眠呼吸暂停指数(central sleep apnea index,CSAI),微觉醒指数(micro-arousal index,MAI)等多导睡眠监测参数及白天Epworth嗜睡评分(ESS),采用酶联免疫吸附试验测定肿瘤坏死因子a(tumor necrosis factor-a,TNF-a).两组间比较采用t检验,组内比较使用单因素方差分析,组内3个阶段两两比较采用q检验,两变量相关分析采用Pearson相关检验. 结果 治疗前2组呼吸暂停低通气指数(apnea hypoapnea index,AHI)、MAI、最低SpO2、ESS评分及血浆TNF-a水平组间比较差异没有统计学意义(t值分别为0.630、1.223、0.691、0.764和0.192,均P>0.05),但残余嗜睡组患者的CSAJ(14.39±4.21)次/h显著高于对照组[(8.58±5.75)次/h,t=4.097,P＜0.05].自动CPAP治疗1个月时2组的AHI、CSM、MAI和ESS评分均明显低于治疗前(g值为0.87～112.55,均P.＜0.05),但残余嗜睡组CSAI、MAI及ESS评分明显高于对照组[CSM:(7.19±1.75)次/h,(3.37±1.04)次/h,t=9.473,P＜O.05;MAI:(9.00±1.95)次/h,(2.36 4-0.66)次/h,f=14.385,P＜0.05;ESS:(9.54 4-0.51)分,(5.42±1.32)分,t=2.857,P＜0.05].ASV治疗时残余嗜睡组与对照组的CSAI、MAI及白天ESS评分均进一步下降,尤以残余嗜睡组的下降更为明显.此外残余嗜睡组内血浆TNF-a水平与治疗前(17.2±3.3)残余嗜睡,μg/L相比,自动CPAP治疗时(16.5 4-3.6)μg/L无明显下降(q值为11.696,P>0.05),但在ASV治疗时(12.6±3.4)μg/L与治疗前相比显著降低(q值为11.696,P＜0.05).血浆TNF-a水平与ESS评分呈显著正线性相关(r=0.503,P＜0.01),与MAI亦呈显著正相关(r=0.545,P＜0.01). 结论 经自动CPAP治疗后OSAS患者的残余嗜睡与治疗前、中存在的CSA事件频率有关.ASV在显著降低CSAI的同时也明显改善了提示ASV可有效治疗OSAS患者的残余嗜睡.TNF-a也与残余嗜睡患者的嗜睡程度相关,可能参与了残余嗜睡的发生.