Magee Michelle, Sletten Tracey L, Ferguson Sally A, Grunstein Ronald R, Anderson Clare, Kennaway David J, Lockley Steven W, Rajaratnam Shantha Mw
Scand J Work Environ Health. 2016 May 1;42(3):217-27. doi: 10.5271/sjweh.3560. Epub 2016 Apr 9.
This study aimed to investigate sleep and circadian phase in the relationships between neurobehavioral performance and the number of consecutive shifts worked.
Thirty-four shift workers [20 men, mean age 31.8 (SD 10.9) years] worked 2-7 consecutive night shifts immediately prior to a laboratory-based, simulated night shift. For 7 days prior, participants worked their usual shift sequence, and sleep was assessed with logs and actigraphy. Participants completed a 10-minute auditory psychomotor vigilance task (PVT) at the start (21:00 hours) and end (07:00 hours) of the simulated night shift. Mean reaction times (RT), number of lapses and RT distribution was compared between those who worked 2-3 consecutive night shifts versus those who worked 4-7 shifts.
Following 4-7 shifts, night shift workers had significantly longer mean RT at the start and end of shift, compared to those who worked 2-3 shifts. The slowest and fastest 10% RT were significantly slower at the start, but not end, of shift among participants who worked 4-7 nights. Those working 4-7 nights also demonstrated a broader RT distribution at the start and end of shift and had significantly slower RT based on cumulative distribution analysis (5 (th), 25 (th), 50 (th), 75 (th)percentiles at the start of shift; 75th percentile at the end of shift). No group differences in sleep parameters were found for 7 days and 24 hours prior to the simulated night shift.
A greater number of consecutive night shifts has a negative impact on neurobehavioral performance, likely due to cognitive slowing.
本研究旨在调查神经行为表现与连续轮班次数之间关系中的睡眠和昼夜节律相位。
34名轮班工作者[20名男性，平均年龄31.8（标准差10.9）岁]在基于实验室的模拟夜班前立即连续工作2 - 7个夜班。在之前的7天里，参与者按照他们平常的轮班顺序工作，通过日志和活动记录仪评估睡眠情况。参与者在模拟夜班开始时（约21:00）和结束时（约07:00）完成一项10分钟的听觉心理运动警觉任务（PVT）。比较连续工作2 - 3个夜班的人与工作4 - 7个夜班的人的平均反应时间（RT）、失误次数和RT分布情况。
与连续工作2 - 3个夜班的人相比，连续工作4 - 7个夜班的夜班工作者在轮班开始和结束时的平均RT明显更长。在连续工作4 - 7个夜班的参与者中，最慢和最快的10%的RT在轮班开始时明显更慢，但在轮班结束时并非如此。连续工作4 - 7个夜班的人在轮班开始和结束时的RT分布也更宽，并且根据累积分布分析（轮班开始时的第5、25、50、75百分位数；轮班结束时的第75百分位数），其RT明显更慢。在模拟夜班前7天和24小时内，未发现两组在睡眠参数上存在差异。
连续更多的夜班对神经行为表现有负面影响，可能是由于认知减慢所致。
