Malow B A, Edwards J, Marzec M, Sagher O, Ross D, Fromes G
Michael S. Aldrich Sleep Disorders Laboratory and the Epilepsy Program, Clinical Neurophysiology Section, Department of Neurology, University of Michigan Medical School, Ann Arbor 48109-0117, USA.
Neurology. 2001 Sep 11;57(5):879-84. doi: 10.1212/wnl.57.5.879.
Given that vagal afferents project to brainstem regions that promote alertness, the authors tested the hypothesis that vagus nerve stimulation (VNS) would improve daytime sleepiness in patients with epilepsy.
Sixteen subjects with medically refractory seizures underwent polysomnography and multiple sleep latency tests (MSLT) and completed the Epworth Sleepiness Scale (ESS), a measure of subjective daytime sleepiness, before and after 3 months of VNS. Most subjects (>80%) were maintained on constant doses of antiepileptic medications.
In the 15 subjects who completed baseline and treatment MSLT, the mean sleep latency (MSL) improved from 6.4 +/- 4.1 minutes to 9.8 +/- 5.8 minutes (+/- SD; p = 0.033), indicating reduced daytime sleepiness. All subjects with stimulus intensities of < or =1.5 mA showed improved MSL. In the 16 subjects who completed baseline and treatment ESS, the mean ESS score decreased from 7.2 +/- 4.4 to 5.6 +/- 4.5 points (p = 0.049). Improvements in MSLT and ESS were not correlated with reduction in seizure frequency. Sleep-onset REM periods occurred more frequently in treatment naps as compared to baseline naps (p < 0.008; Cochran-Mantel-Haenszel test). The amount of REM sleep or other sleep stages recorded on overnight polysomnography did not change with VNS treatment.
Treatment with VNS at low stimulus intensities improves daytime sleepiness, even in subjects without reductions in seizure frequency. Daytime REM sleep is enhanced with VNS. These findings support the role of VNS in activating cholinergic and other brain regions that promote alertness.
鉴于迷走神经传入纤维投射至促进警觉性的脑干区域，作者检验了迷走神经刺激（VNS）可改善癫痫患者日间嗜睡的假说。
16例药物难治性癫痫患者在VNS治疗3个月前后接受了多导睡眠图和多次睡眠潜伏期试验（MSLT），并完成了Epworth嗜睡量表（ESS），这是一种主观日间嗜睡的测量方法。大多数受试者（>80%）维持恒定剂量的抗癫痫药物治疗。
在完成基线和治疗期MSLT的15例受试者中，平均睡眠潜伏期（MSL）从6.4±4.1分钟改善至9.8±5.8分钟（±标准差；p = 0.033），表明日间嗜睡减轻。所有刺激强度≤1.5 mA的受试者MSL均有改善。在完成基线和治疗期ESS的16例受试者中，平均ESS评分从7.2±4.4降至5.6±4.5分（p = 0.049）。MSLT和ESS的改善与癫痫发作频率的降低无关。与基线期小睡相比，治疗期小睡中睡眠始发快速眼动期出现得更频繁（p < 0.008； Cochr an-Mantel-Haenszel检验）。夜间多导睡眠图记录的快速眼动睡眠量或其他睡眠阶段在VNS治疗后未发生变化。
低刺激强度的VNS治疗可改善日间嗜睡，即使在癫痫发作频率未降低的受试者中也是如此。VNS可增强日间快速眼动睡眠。这些发现支持了VNS在激活促进警觉性的胆碱能及其他脑区中的作用。
