Aging young sleep: a test of the phase advance hypothesis of sleep disturbance in the elderly

SUMMARY  With aging, the phase relationship between sleep and body core temperature is altered such that the temperature minimum occurs substantially earlier in the major nocturnal sleep period. The sleep maintenance difficulties that often accompany normal aging are generally assumed to be associated with this age-related change in the phase angle between sleep and temperature. To test this notion, we used timed exposure to bright light to reproduce in healthy young adults a similar phase relationship between temperature and sleep, to determine if such a manipulation would induce the same fragmented nocturnal sleep commonly observed in individuals over 65 years of age. Seven young adults were exposed to morning bright light for 3 consecutive days following a baseline night. Bright light exposure caused a 97 min phase advance of the fitted temperature minimum when compared with baseline. Significant declines in several measures of sleep quality were associated with the phase advance, including wakefulness after initial sleep onset (WASO), sleep efficiency and number of stage changes. Yet, the severity of sleep disturbance exhibited by these subjects did not approach that exhibited by most elderly subjects. The findings suggest that while chronophysiological changes appear to be strongly associated with the tendency to awaken in the early morning, they cannot account entirely for the severity of sleep disturbance frequently observed in older subjects.     

The nasopharyngeal prong airway: an effective post-operative adjunct after adenotonsillectomy for obstructive sleep apnoea in children

OBJECTIVES: Obstructive sleep apnoea is a common childhood disorder. Adenotonsillar enlargement is most commonly implicated, with adenotonsillectomy representing an effective treatment in the majority of cases. Such children may develop respiratory compromise post-operatively, sometimes necessitating admission to the intensive care unit. We describe insertion of a nasopharyngeal "prong" airway and evaluate its benefits after adenotonsillectomy for obstructive sleep apnoea and milder forms of sleep-disordered breathing. METHODS: The prong is easily fashioned from a paediatric endotracheal tube. It is inserted once surgery is complete, remaining in situ overnight. We retrospectively examine its elective use over an 18-month period in selected children considered to be at high risk of post-operative respiratory compromise. Existing practice over the preceding 18-month period is also examined, by way of comparison. RESULTS: Forty-three children underwent adenotonsillectomy for sleep-disordered breathing/OSAS in the 18 months prior to introduction of the prong. Ten were considered "high risk" cases: post-operative intensive care beds were pre-booked for these, but none were eventually required. During the subsequent 18 months, 60 children underwent adenotonsillectomy for the same indication. Seventeen "high risk" cases received the prong post-operatively. No intensive care beds were pre-booked and all children were managed safely on the ENT ward, with minimal intervention. CONCLUSIONS: Use of a nasopharyngeal prong significantly improves the post-operative course of selected children who are at high risk of respiratory compromise after adenotonsillectomy. This largely avoids the need for medical intervention and intensive care admission.     

Sleep,Physical Activity,and General Health Status: US Pediatricians and the General US Adult Population

Objective

To examine US pediatricians and US adults on 3 self-reported health measures (sleep, physical activity, and general health status) and to assess factors related to these measures for each group.

A preliminary investigation of sleep quality and patient‐reported outcomes in pediatric solid organ transplant candidates

The current cross‐sectional, single‐center study aimed to examine sleep quality in a sample of adolescents awaiting solid organ transplantation and to explore associations between sleep quality and both health‐related quality of life and barriers to adherence. Thirty adolescents between the ages of 12 and 18 years (M age = 15.26, SD = 1.89) who were awaiting transplantation participated in this study. Participants completed measures of sleep quality, health‐related quality of life, and barriers to adherence. T test and correlational analyses were performed to examine study aims. Adolescents awaiting transplantation had significantly lower levels of overall sleep quality compared to published norms of healthy peers. Domains of sleep quality were positively related to emotional and psychosocial health‐related quality of life. Sleep quality domains were also negatively related to adherence barriers. This study provides preliminary evidence demonstrating that sleep quality among transplant candidates is compromised, and that poor sleep quality is related to adolescents’ functioning across a number of domains during the pretransplant period. Results highlight the clinical importance of assessing and targeting sleep functioning in adolescents awaiting transplantation in order to reduce the negative influence of suboptimal sleep on functioning during this vulnerable period.     

阻塞性睡眠呼吸暂停低通气综合征患者不同刺激率ABR结果分析

目的：探讨高刺激率ABR对阻塞性睡眠呼吸暂停低通气综合征（obstructive sleep apnea－hypopnea syndrome,OSAHS）患者听力评估的价值及其与低氧血症的相关性。方法对39例（78耳）OSAHS患者（中度5例、重度34例）和34例（68耳）正常成年人分别进行11．1、31．1、51．1次/秒刺激率的听性脑干反应（ABR）测试,比较组间结果,并与多导睡眠监测呼吸暂停低通气指数（AHI）、最低血氧饱和度（LSaO2）、平均血氧饱和度（MSaO2）、氧饱和度≤90％的时间占总监测时间的百分比（SIT90）、氧饱和度≤80％的时间占总监测时间的百分比（SIT80）进行相关性分析。结果在11．1次/秒刺激率时OSAHS组ABR波Ⅴ潜伏期（5．79±0．22 ms）较对照组（5．67±0．24 ms）延长;31．1次/秒刺激率时OSAHS组ABR 波Ⅰ潜伏期（1．85±0．18 ms）、波Ⅴ潜伏期（5．98±0．19 ms）均较对照组（分别为1．76±0．16 ms、5．82±0．24 ms）延长;在51．1次/秒刺激率时OSAHS组ABR波Ⅰ潜伏期（1．94±0．26 ms）、波Ⅴ潜伏期（6．09±0．25 ms）较对照组（分别为1．83±0．15 ms、5．99±0．24 ms）延长。刺激率由11．1次/秒升高至31．1次/秒时,OSAHS 组波Ⅰ潜伏期延长,ΔⅠ31．1－11．1（0．12±0．17ms）较对照组（0．07±0．11 ms）长,刺激率由11．1次/秒升高至51．1次/秒时,OSAHS组波Ⅰ潜伏期延长,ΔⅠ51．1－11．1（0．21±0．25 ms）较对照组（0．15±0．10 ms）长。ΔⅠ31．1－11．1与LSaO2负相关（r＝－0．24）,与SIT90（r＝0．23）、SIT80（r＝0．27）正相关;ΔⅠ51．1－11．1与LSaO2（r＝－0．33）、MSaO2（r＝－0．35）负相关,与SIT90（r＝0．37）、SIT80（r＝0．29）正相关;以上差异及相关性均有统计学意义（p＜0．05）。结论高刺激率ABR可发现中度及重度OSAHS患者耳蜗及听神经近耳蜗段的损伤。     

阻塞性睡眠呼吸暂停低通气综合征与成纤维细胞生长因子21

阻塞性睡眠呼吸暂停低通气综合征（OSAHS）发病率逐年升高,已经成为危害人类健康的主要疾病之一。迄今为止,OSAHS 的发病机制尚未阐明。成纤维细胞生长因子21（FGF21）是参与糖脂代谢的一种重要蛋白质。近年来大量的研究显示 FGF21与 OSAHS 的发生发展有密切的联系。本文就近些年 OSAHS 与 FGF21的相关研究进行简要综述。     

Assessment of adenotonsillar size and caregiver-reported sleep symptoms among 3–6 year old children undergoing adenotonsillectomy

IntroductionAdenotonsillectomy remains the accepted first-line treatment for obstructive sleep apnea syndrome (OSAS) in children. Tonsillar size may be especially relevant in risk stratification as it may impact symptoms of sleep disordered breathing (SDB). This study assesses correlations among subjective tonsillar grading, measured tonsillar size, and degree of adenoid obstruction in patients age 3–6 years with caregiver-reported symptoms.MethodsChildren 3–6 years old undergoing adenotonsillectomy for OSAS were enrolled prospectively. The subjective tonsillar grade and degree of adenoid obstruction were recorded on physical examination by the otolaryngologist, and the objective tonsillar size was obtained from pathology reports. Spearman's rho was used to assess agreement among measures of tonsillar size and adenoid obstruction; and to correlate these measures with caregiver-reported SDB symptoms obtained from a pre-operative standardized questionnaire.ResultsThe cohort included 103 boys and 97 girls of median age 4.8 (interquartile range [IQR]: 3.9, 5.9) years. Median subjective tonsillar grade was 3+ (IQR: 3+, 4+) while median tonsillar size was 2.7 cm (IQR: 2.5, 3) and median adenoid obstruction was 60% (IQR: 50%, 80%). The subjective tonsillar grade and measured tonsillar size were strongly correlated (ρ = 0.31, p < 0.001), whereas adenoid obstruction was uncorrelated with either subjective tonsillar grade (ρ = 0.01, p = 0.860) or measured size (ρ = −0.05, p = 0.497). Tonsillar grade was positively correlated with 3 common caregiver-reported SDB symptoms (loud snoring, trouble breathing at night, and daytime sleepiness). Objective tonsillar size was positively correlated only with difficulty organizing tasks or activities, and adenoid obstruction was positively correlated only with stopping breathing during sleep.ConclusionSubjective tonsillar grading by the otolaryngologist achieved better correlation than measured tonsillar size or degree of adenoid obstruction with caregiver-reported SDB symptoms in children 3–6 years of age undergoing adenotonsillectomy.     

Empirical Note: Self-Report Versus Recorded Sleep in Healthy Seniors

Although insomnia is a major public health problem in the elderly, little information concerning the relation between subjective reports of sleep and laboratory measures in the elderly has been published. Also, while laboratory studies of the healthy elderly typically show that women steep better than men, epidemiologic studies suggest that women complain more often than men about disturbed sleep. We report here a study of 20 healthy elderly subjects without sleep complaints (10M. 10F), in which relations between subjective and objective measures of sleep were explored. Both men and women showed significant correlations between objective measures of Sleep Latency (SL) and subjective estimates of fall asleep time; similarly, in both groups, subjective estimates of sleep duration were significantly and positively correlated with Time Spent Asleep (TSA). However, in the women, but not in the men, “restlessness” of sleep was significantly correlated with WASO (wake time after sleep onset), while “soundness” of sleep was positively related to amount of slow wave sleep. In general, women showed a higher proportion of significant and more stable correlations between subjective and objective measures than did men. These findings suggest that elderly women may report sleep loss more accurately than elderly men.     

Suppression of electroencephalogram Δ power density during non-rapid eye movement sleep as a result of a prolonged cognitive task prior to sleep onset

The effects of a prolonged cognitive task prior to sleep onset on subsequent sleep patterns were examined in 14 healthy subjects who were randomly assigned to two conditions. Those assigned to a working condition were asked to engage in a prolonged cognitive task until close to bedtime (0200 hours), whereas those assigned to a relaxing condition were instructed to perform the same task during the daytime and then to stay awake in a relaxed state until the same bedtime as the work group. Visual scoring of sleep stages showed no significant differences in the amounts of stage 4 and slow wave sleep (stage 3+4) between the two conditions. Power spectrum analysis of sleep electroencephalogram (EEG) revealed that the EEG (0.5–4.0 Hz) power density in the first non-rapid eye movement (REM)-REM sleep cycle was significantly lower following the prolonged cognitive task prior to sleep onset than following the relaxed wakefulness and that the decreased EEG power density in the first sleep cycle was not compensated for during the later part of the sleep. These findings would indicate that the prolonged cognitive task prior to sleep onset may suppress EEG power density during subsequent sleep, suggesting that such a task may interfere with the development of deep non-REM sleep.     

Wavelets-a new tool in sleep biosignal analysis

SUMMARY  The wavelet transform is a relatively new approach to data processing which has been applied in different areas such as signal, speech and image processing. In the last decade, many papers have been published on wavelet theory and its applications. The wavelet transform provides an elegant alternative to the classical Fourier or Gabor transforms unifying numerous signal processing techniques in a common framework. The purpose of the present paper is to provide an overview of the applicability of the wavelet transform to EEG signal analysis. In the first part of the paper the mathematical background is summarized. In the second part, applications to the sleep EEG field are presented and discussed. The results of these illustrations demonstrate the usefulness of the wavelet transform to solve various problems including signal parametrization, pattern recognition and biosignal representation.