EFFECT OF PARTIAL DEPRIVATION ON BOTH DAYTIME VIGILANCE MEASURES AND NOCTURNAL RESPIRATORY DISORDER VARIABLES IN OBSTRUCTIVE SLEEP APNEA SYNDROME

众所周知，睡眠不足会增加白天的嗜睡感，同时也会降低上呼吸道扩张肌肉的张力。然而，早期部分睡眠剥夺对阻塞性睡眠呼吸暂停综合征(OSAS)患者白天警觉和夜间呼吸紊乱措施的影响尚未得到很好的阐明。为了阐明这一问题，我们进行了一系列研究，探讨了早期部分睡眠剥夺对OSAS患者日间功能指标和夜间睡眠变量的影响。研究对象包括10名未经治疗的OSAS患者(男：女=7：3，平均年龄29.7±3.4岁)和10名健康对照组(男：女=8：2，29.8±4.5岁)，他们都有正常的睡眠时间表和平均睡眠保持潜伏期(MWT)正常值(20分钟法；12分钟或以上)。在两周令人满意的夜间睡眠后，受试者接受了多导睡眠图记录，然后进行了日间警戒(ex…在正常睡眠状态下(0：00~7：00睡眠)和早期部分睡眠剥夺状态下(SD；睡眠时间限制在3：00~7：00之间)，包括MWT、精神运动警觉测试(PVT)和事件相关电位(P300)。采用随机交叉的方法对所有受试者进行排序，比较正常组和SD 3天恢复夜PSG的夜间睡眠结构，发现恢复夜两组的睡眠潜伏期均高于正常夜，而睡眠潜伏期百分比和睡眠潜伏期均小于正常夜。在呼吸紊乱变量方面，两组患者在康复之夜均表现出较高的呼吸暂停低通气指数。然而，只有阻塞性睡眠呼吸暂停综合征患者在康复之夜呼吸暂停和低呼吸发作次数显著延长，夜间经皮血氧饱和度(SaO2)显著增加。在日间心理生理指标中，SD状态下两组P300潜伏期均显著延长。而P300波幅在此条件下较小，仅在OSAS组出现。在PVT变量方面，反应失误和SD的假反应数目仅在OSAS组显著增加。在MWT方面，两组受试者在SD状态下的平均睡眠潜伏期较正常状态下显著缩短。但OSAS组SD潜伏期下降率明显高于健康对照组，提示OSAS组夜间呼吸紊乱变量的恶化尤其是呼吸事件的延长导致夜间氧减饱和加重更为突出。此外，OSAS组在SD期间以MWT估计的客观日间嗜睡增加、P300表现的脑信息加工和PVT表现的警觉依赖性精神运动功能的恶化均明显高于健康组。这些发现给人留下了深刻的印象，即使是三天的部分睡眠剥夺也会加剧呼吸障碍本身和日间嗜睡及其相关的精神运动障碍，特别是在OSAS患者中。我们想要强调OSAS早期治疗的必要性和在这一人群中保持正确睡眠卫生的意识。较少

It has been well known that sleep deprivation brings both elevation of daytime sleepiness and decrease in the tonus of upper airway dilating muscles. However, influence of early partial sleep deprivation on the daytime vigilance and nocturnal respiratory disorder measures in obstructive sleep apnea syndrome (OSAS) has not been well elucidated. In order to clarify this issue, we made a series of the study on the effect of early partial sleep deprivation on the daytime functioning measures and nocturnal sleep variables of OSAS patients.Subjects of this study comprised of both ten untreated OSAS subjects (M:F=7:3, mean age with 29.7 ±3.4 years) and 10 healthy normal controls (M:F=8:2, 29.8±4.5 years) with both normal sleep schedule and normal values of mean sleep latency of maintenance of wakefulness test (MWT) (20 minutes method ; 12 minutes or above). After two weeks of satisfactory nocturnal sleep, the subjects underwent polysomnographic recording (PSG) followed by daytime vigilance ex … More amination including MWT, psychomotor vigilance test (PVT) and event related potentials (P300) under normal sleep condition (subjects slept during the period from 0:00 to 7:00) and condition with early partial sleep deprivation (SD ; sleep period was restricted to the period from 3:00 to 7:00). Order of these conditions was assigned to all the subjects with randomized cross over manner.When comparison of nocturnal sleep structure on PSG between normal condition and recovery night from three days of SD, both group showed higher values of sleep latency and smaller values of both % stage REM and sleep latency on recovery night compared with those on the night of normal condition. As for respiratory disorder variables, both groups showed higher values of apnea hypopnea index on the recovery night. However, significant prolongation of episodes of both apnea and hypopnea as well as significant increase in the nocturnal percutaneous oxygen desaturation(SaO2) on the recovery night was recognized only in the group with OSAS. Among daytime psychophysiological measures, latency of P300 was significantly longer under SD condition in both groups. On the other hand, smaller value of the amplitude of P300 under that condition was recognized only in the group with OSAS. With respect to PVT variables, significant increase in the number of both reaction lapse and false response with SD was recognized only in the group with OSAS. Regarding MWT, mean sleep latency was significantly shorter under SD condition compared with normal condition in the subject two groups. However, rate of decrease in the latency during SD was significantly higher in the group with OSAS compared with healthy control group.From these results, it was revealed that worsening of nocturnal respiratory disorder variables especially prolongation of respiratory events leading to the aggravation of nocturnal oxygen desaturation on the recovery night was more prominent in the group with OSAS. Moreover, increase in objective daytime sleepiness estimated with MWT and deterioration of both cerebral information process manifested on P300 as well as vigilance dependent psychomotor function manifested on PVT during SD was more marked in the OSAS group than in the healthy group. These findings strongly impress that partial sleep deprivation even for three days could act to aggravate respiratory disorder itself and daytime sleepiness as well as its related psychomotor dysfunctioning especially in OSAS patients. We want to emphasize the necessity of both the early treatments of OSAS and the awareness of maintaining correct sleep hygiene in this patients population. Less