Crowley Stephanie J, Poole Elaine, Adams John, Eastman Charmane I
Biological Rhythms Research Laboratory, Department of Psychiatry & Behavioral Sciences, Rush University Medical Center, Chicago IL, USA.
Olivet Nazarene University, Department of Behavioral Sciences, Bourbonnais, IL, USA.
Sleep Adv. 2024 Aug 31;5(1):zpae065. doi: 10.1093/sleepadvances/zpae065. eCollection 2024.
Our sleep extension intervention in adolescents showed that gradually shifting weekday bedtime earlier plus one weekend of morning bright light advanced circadian phase and increased weeknight sleep duration. Here, we examine at-home maintenance of these changes.
Fourteen adolescents (15.3-17.9 years; 7 female) completed a 7-week study. After usual sleep at home (2-week baseline), intervention participants ( = 8) gradually advanced weekday bedtime (1 hour earlier than baseline during week 3; 2 hours earlier in week 4) and received bright light (~6000 lux; 2.5 hours) on both mornings of the intervening weekend. During three maintenance weeks, intervention participants were instructed to maintain their school-day wake-up time on all days, keep their early week four bedtimes, except on weekends when they could go to bed up to 1 hour later, and get a 2.5-hour light box exposure within 5 minutes of waking on one morning (Saturday or Sunday) of both weekends at home. Control participants ( = 6) slept as usual at home and did not receive weekend bright light. Dim light melatonin onset (DLMO) was measured after the 2-week baseline, 2-week intervention, and 3-week maintenance in all participants. Actigraphic sleep-wake was collected throughout.
After the 2-week intervention, DLMOs advanced more compared to control (37.0 ± 40.0 minutes vs. -14.7 ± 16.6 minutes), weekday sleep duration increased by 69.7 ± 27.8 minutes and sleep onset was 103.7 ± 14.2 minutes earlier compared to baseline. After three maintenance weeks, intervention participants showed negligible DLMO delays (-4.9 ± 22.9 minutes); weekday fall-asleep times and sleep durations also remained stable.
Early circadian phase and extended sleep can be maintained with at-home weekend bright light.
我们对青少年进行的睡眠延长干预表明，工作日就寝时间逐渐提前，加上一个周末的早晨强光照射，可使昼夜节律提前，并增加工作日夜间的睡眠时间。在此，我们研究这些变化在家庭环境中的维持情况。
14名青少年（年龄15.3 - 17.9岁；7名女性）完成了一项为期7周的研究。在在家正常睡眠（2周基线期）后，干预组参与者（n = 8）逐渐提前工作日就寝时间（第3周比基线提前1小时；第4周提前2小时），并在干预周末的两个早晨接受强光照射（约6000勒克斯；2.5小时）。在三个维持周期间，干预组参与者被要求在所有日子保持上学日的起床时间，保持第4周初的就寝时间，但周末可以晚睡1小时，并且在在家的两个周末的其中一个早晨（周六或周日）醒来后5分钟内接受2.5小时的灯箱照射。对照组参与者（n = 6）在家照常睡眠，未接受周末强光照射。在所有参与者的2周基线期、2周干预期和3周维持期后测量暗光褪黑素起始时间（DLMO）。全程收集活动记录仪记录的睡眠 - 觉醒数据。
2周干预后，与对照组相比，干预组的DLMO提前更多（37.0 ± 40.0分钟 vs. -14.7 ± 16.6分钟），工作日睡眠时间增加了69.7 ± 27.8分钟，入睡时间比基线提前了103.7 ± 14.2分钟。经过三个维持周后，干预组参与者的DLMO延迟可忽略不计（-4.9 ± 22.9分钟）；工作日入睡时间和睡眠时间也保持稳定。
通过在家进行周末强光照射可以维持早期昼夜节律和延长睡眠时间。
