METHODS: Nineteen healthy participants (Mean±SD 29±10 years, 12 males, 7 females) were recruited to a laboratory study consisting of two counterbalanced 8-day lighting conditions (order randomized) 1-month apart: 1) control lighting condition- dim, blue-depleted and 2) circadian-informed lighting condition- blue-enriched and blue-depleted where appropriate. Participants underwent an adaptation night (22:00h - 07:00h), then four nights of simulated nightwork (cognitive testing battery of nine tasks, 00:00h - 08:00h) and sleep during the day (10:00h - 19:00h). Psychomotor vigilance task (PVT) lapses, Karolinska Sleepiness Scale (KSS) scores, and polysomnography-derived sleep outcomes were compared between conditions and across days using mixed models.
RESULTS: Significant condition-by-day-by-time of task interaction effects were found for PVT lapses, median reaction time, and reaction speed, with ~50% fewer lapses by the end of simulated shiftwork with circadian-informed lighting versus control (mean±SD 7.4±5.0 vs. 15.6±6.1). KSS was lower around the nightshift midpoints on days 6 and 7 with circadian versus control lighting. Participants slept 52 minutes longer [95% CIs: 27.5, 76.5 mins] by Day 7 with circadian-informed versus control lighting, p<0.001. Effects were inconsistent on other performance tasks.
CONCLUSIONS: Circadian-informed lighting improved sleep, sleepiness, and vigilance compared to control lighting. These findings support the potential for lighting interventions to improve sleep and vigilance in night shift workers chronically exposed to dim lighting.
方法:19名健康参与者(平均值±SD29±10年,12名男性,7名女性)被招募到一项实验室研究,该研究由两个平衡的8天照明条件(随机顺序)间隔1个月组成:1)控制照明条件-昏暗,蓝色耗尽和2)昼夜节律通知的照明条件-在适当的情况下富含蓝色和蓝色耗尽。参与者经历了一个适应之夜(22:00h-07:00h),然后是四个晚上的模拟夜间工作(九个任务的认知测试电池,00:00h-08:00h)和白天睡眠(10:00h-19:00h)。精神运动警惕任务(PVT)失效,卡罗林斯卡嗜睡量表(KSS)评分,和多导睡眠图得出的睡眠结果使用混合模型在不同条件和不同天数之间进行比较.
结果:对于PVT失误,发现了任务交互效应的显着逐日条件,中值反应时间,和反应速度,与控制相比,通过昼夜节律照明的模拟移位结束时,失误减少了约50%(平均值±SD7.4±5.0与15.6±6.1)。在第6天和第7天,夜班中点附近的KSS较低,昼夜节律照明与对照照明。到第7天,参与者的睡眠时间延长了52分钟[95%CIs:27.5,76.5分钟],具有昼夜节律的照明与控制照明,p<0.001。对其他绩效任务的影响不一致。
结论:昼夜节律照明改善了睡眠,困倦,与控制照明相比,保持警惕。这些发现支持了照明干预措施的潜力,以改善长期暴露于昏暗照明的夜班工人的睡眠和警惕性。