Nicoletti Corinne, Müller Christian, Hayashi Chiemi, Nakaseko Masaru, Tobita Itoko, Läubli Thomas
Department of Health Sciences and Technology, ETH Zurich, Sonneggstrasse 3, 8092, Zurich, Switzerland,
Eur J Appl Physiol. 2015 Jun;115(6):1313-20. doi: 10.1007/s00421-015-3110-3. Epub 2015 Jan 23.
The study investigates if the circadian rhythm of heart rate is apparent during the working periods of day and night shifts in Swiss and Japanese nurses and if it is influenced by work organization. For a better interpretation of the heart rate, the activity profile over these working periods was monitored.
Heart rate and activity profile of 18 Swiss and 24 Japanese nurses were measured during one day and one night shift. The day and the night shift data of each subject were combined, resulting in an approximately 18-h working period.
A significant time effect of the mean hourly value of the heart rate was found in Swiss nurses (change in amplitude 7.1 bpm) as well as in Japanese nurses (11.8 bpm). These effects could be modeled with cosine curves for the Swiss and Japanese subjects. For the activity level significant time effects, similar to the ones in heart rate, were found in Swiss nurses (87 % of SD) but not in Japanese nurses (26 % of SD).
We found a significant time effect in heart rate similar to the known circadian rhythm under normal sleep-wake conditions while working in the studied shift work schedules. In the Japanese nurses, studied heart rate followed a circadian rhythm independently of the level of physical activity. Therefore, an activity profile following the circadian rhythm, especially a reduced workload from 2 to 4 a.m., is proposed. The proposed activity profile could be reached with an adapted work organization.
本研究调查瑞士和日本护士在日班和夜班工作期间心率的昼夜节律是否明显，以及是否受工作安排的影响。为了更好地解读心率，监测了这些工作期间的活动情况。
测量了18名瑞士护士和24名日本护士在一个白班和一个夜班期间的心率及活动情况。将每个受试者的白班和夜班数据合并，形成一个约18小时的工作时间段。
瑞士护士（心率平均每小时变化幅度7.1次/分钟）和日本护士（11.8次/分钟）的心率平均每小时值均存在显著的时间效应。这些效应可用瑞士和日本受试者的余弦曲线进行模拟。对于活动水平，瑞士护士存在与心率类似的显著时间效应（标准差的87%），而日本护士则没有（标准差的26%）。
我们发现在所研究的轮班工作安排下工作时，心率存在与正常睡眠-觉醒条件下已知的昼夜节律类似的显著时间效应。在日本护士中，所研究的心率遵循昼夜节律，与身体活动水平无关。因此，建议制定一个遵循昼夜节律的活动计划，尤其是在凌晨2点至4点减少工作量。通过调整工作安排可以实现所建议的活动计划。
