Hornyak Magdolna, Feige Bernd, Voderholzer Ulrich, Riemann Dieter
Department of Psychiatry and Psychotherapy, University Hospital, Hauptstrasse 5, D-79104 Freiburg, Germany.
Clin Neurophysiol. 2005 Jun;116(6):1265-72. doi: 10.1016/j.clinph.2005.02.004. Epub 2005 Mar 31.
Conventional analyses of sleep EEG recordings according to standard criteria indicate severe sleep disturbances in patients with restless legs syndrome (RLS). Spectral analysis of sleep EEG may be a sensitive tool to detect functional alterations of sleep mechanisms beyond the visual scoring of polysomnographic records. We analysed sleep EEG spectral power differences between RLS patients and healthy subjects. Furthermore, we studied the relationship of sleep EEG spectral power to the occurrence of periodic leg movements in sleep (PLMS) and arousal events.
Sleep EEGs from 20 patients with idiopathic RLS and of 20 age and sex matched healthy subjects were investigated. The spectral analysis was carried out on the same 30s epochs for which sleep stages had been determined. As a first step, whole-night spectral power excluding epochs with an arousal or with a PLMS was compared separately for REM and NREM sleep between RLS and healthy subjects. In a second step, we evaluated the spectral effects of PLMS, PLMS with associated arousals and isolated arousals relative to epochs of sleep without such events in both groups. In this part of the analysis, we only included the epochs of sleep stage 2 (the main and most stable non-REM sleep stage) and of REM sleep.
Spectral power of all sleep epochs (excluding arousals and PLMS) did not differ between patients with RLS and healthy subjects. As expected, arousals and PLMS-associated arousals resulted in a significant increase in higher-frequency activity (alpha, beta1, beta2 and gamma bands) in both groups. Spectral power in epochs with PLMS alone did not significantly differ from spectral power in epochs without PLMS and without arousal in any of the groups.
We found no evidence for an altered cortical activity in sleep stage 2 and REM sleep epochs in RLS patients compared to that in healthy controls if epochs with arousals were not considered. Furthermore, while PLMS associated with an arousal have a high impact on EEG spectra, the effect of a PLMS without arousal seems to be minor and transient.
Our data suggest that RLS related symptoms may intermittently disrupt sleep but do not appear to involve a persistent disturbance of the basic sleep generating patterns.
根据标准标准对睡眠脑电图记录进行的传统分析表明，不安腿综合征（RLS）患者存在严重的睡眠障碍。睡眠脑电图的频谱分析可能是一种敏感工具，可检测多导睡眠图记录视觉评分之外睡眠机制的功能改变。我们分析了RLS患者与健康受试者之间睡眠脑电图频谱功率差异。此外，我们研究了睡眠脑电图频谱功率与睡眠中周期性腿部运动（PLMS）及觉醒事件发生之间的关系。
对20例特发性RLS患者及20例年龄和性别匹配的健康受试者的睡眠脑电图进行研究。对已确定睡眠阶段的相同30秒时间段进行频谱分析。第一步，分别比较RLS患者与健康受试者在快速眼动（REM）睡眠和非快速眼动（NREM）睡眠中，排除有觉醒或PLMS的时间段后的全夜频谱功率。第二步，相对于两组中无此类事件的睡眠时间段，我们评估了PLMS、伴有觉醒的PLMS及孤立觉醒的频谱效应。在这部分分析中，我们仅纳入了睡眠2期（主要且最稳定的非快速眼动睡眠阶段）和REM睡眠的时间段。
RLS患者与健康受试者之间所有睡眠时间段（排除觉醒和PLMS）的频谱功率无差异。正如预期的那样，觉醒及与PLMS相关的觉醒在两组中均导致高频活动（α、β1、β2和γ频段）显著增加。仅出现PLMS的时间段的频谱功率与任何组中无PLMS且无觉醒的时间段的频谱功率无显著差异。
如果不考虑有觉醒的时间段，我们发现与健康对照相比，RLS患者在睡眠2期和REM睡眠时间段中没有证据表明皮质活动发生改变。此外，虽然与觉醒相关的PLMS对脑电图频谱有很大影响，但无觉醒的PLMS的影响似乎较小且短暂。
我们的数据表明，RLS相关症状可能会间歇性地扰乱睡眠，但似乎并不涉及基本睡眠生成模式的持续干扰。
