Moderie Christophe, Van der Maren Solenne, Dumont Marie
Center for Advanced Research in Sleep Medicine, Sacre-Coeur Hospital of Montreal, Montreal, Canada; Department of Psychiatry, University of Montreal, Montreal, Canada.
Center for Advanced Research in Sleep Medicine, Sacre-Coeur Hospital of Montreal, Montreal, Canada; Department of Psychology, University of Montreal, Montreal, Canada.
Sleep Med. 2017 Jun;34:148-155. doi: 10.1016/j.sleep.2017.03.021. Epub 2017 Apr 4.
To assess factors that might contribute to a delayed sleep schedule in young adults with sub-clinical features of delayed sleep phase disorder.
Two groups of 14 young adults (eight women) were compared: one group complaining of a delayed sleep schedule and a control group with an earlier bedtime and no complaint. For one week, each subject maintained a target bedtime reflecting their habitual sleep schedule. Subjects were then admitted to the laboratory for the assessment of circadian phase (dim light melatonin onset), subjective sleepiness, and non-visual light sensitivity. All measures were timed relative to each participant's target bedtime. Non-visual light sensitivity was evaluated using subjective sleepiness and salivary melatonin during 1.5-h exposure to blue light, starting one hour after target bedtime.
Compared to control subjects, delayed subjects had a later circadian phase and a slower increase of subjective sleepiness in the late evening. There was no group difference in non-visual sensitivity to blue light, but we found a positive correlation between melatonin suppression and circadian phase within the delayed group.
Our results suggest that a late circadian phase, a slow build-up of sleep need, and an increased circadian sensitivity to blue light contribute to the complaint of a delayed sleep schedule. These findings provide targets for strategies aiming to decreasing the severity of a sleep delay and the negative consequences on daytime functioning and health.
评估可能导致具有延迟睡眠相位障碍亚临床特征的年轻人睡眠时间表延迟的因素。
比较两组各14名年轻人（8名女性）：一组抱怨睡眠时间表延迟，另一组为对照组，其就寝时间较早且无此类抱怨。在一周时间里，每个受试者维持一个反映其习惯性睡眠时间表的目标就寝时间。然后，受试者被送入实验室，以评估昼夜节律相位（暗光褪黑素开始分泌时间）、主观嗜睡程度和非视觉光敏感性。所有测量均相对于每个参与者的目标就寝时间进行计时。非视觉光敏感性通过在目标就寝时间后一小时开始的1.5小时蓝光照射期间的主观嗜睡程度和唾液褪黑素进行评估。
与对照组相比，睡眠延迟组的昼夜节律相位较晚，且在深夜主观嗜睡程度的增加较慢。两组在对蓝光的非视觉敏感性方面没有差异，但我们发现睡眠延迟组中褪黑素抑制与昼夜节律相位之间存在正相关。
我们的结果表明，较晚的昼夜节律相位、睡眠需求的缓慢积累以及对蓝光的昼夜节律敏感性增加，是导致睡眠时间表延迟抱怨的原因。这些发现为旨在减轻睡眠延迟严重程度及其对白天功能和健康的负面影响的策略提供了目标。
