Lim Yin Cheng, Hoe Victor C W, Darus Azlan, Bhoo-Pathy Nirmala
Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
Environmental Health Research Centre, Institute Medical Research (IMR), National Institute of Health, Kuala Lumpur, Malaysia.
BMJ Open. 2020 Sep 6;10(9):e034455. doi: 10.1136/bmjopen-2019-034455.
Night-shift work may adversely affect health. This study aimed to determine the impact of night-shift work on health-related quality of life (HRQoL), and to assess whether sleep quality was a mediating factor.
A cross-sectional study.
11 manufacturing factories in Malaysia.
177 night-shift workers aged 40-65 years old were compared with 317 non-night-shift workers.
Participants completed a self-administered questionnaire on socio-demographics and lifestyle factors, 12-item Short Form Health Survey V.2 (SF-12v2) and the Pittsburgh Sleep Quality Index (PSQI). The Baron and Kenny's method, Sobel test and multiple mediation model with bootstrapping were applied to determine whether PSQI score or its components mediated the association between night-shift work and HRQoL.
Night-shift work was associated with sleep impairment and HRQoL. Night-shift workers had significantly lower mean scores in all the eight SF-12 domains (p<0.001). Compared with non-night-shift workers, night-shift workers were significantly more likely to report poorer sleep quality, longer sleep latency, shorter sleep duration, sleep disturbances and daytime dysfunction (p<0.001). Mediation analyses showed that PSQI global score mediated the association between night-shift work and HRQoL. 'Subjective sleep quality' (indirect effect=-0.24, SE=0.14 and bias corrected (BC) 95% CI -0.58 to -0.01) and 'sleep disturbances' (indirect effect=-0.79, SE=0.22 and BC 95% CI -1.30 to -0.42) were mediators for the association between night-shift work and physical well-being, whereas 'sleep latency' (indirect effect=-0.51, SE=0.21 and BC 95% CI -1.02 to -0.16) and 'daytime dysfunction' (indirect effect=-1.11, SE=0.32 and BC 95% CI -1.86 to -0.58) were mediators with respect to mental well-being.
Sleep quality partially explains the association between night-shift work and poorer HRQoL. Organisations should treat the sleep quality of night-shift workers as a top priority area for action to improve their employees' overall wellbeing.
夜班工作可能对健康产生不利影响。本研究旨在确定夜班工作对健康相关生活质量（HRQoL）的影响，并评估睡眠质量是否为中介因素。
一项横断面研究。
马来西亚的11家制造工厂。
177名年龄在40 - 65岁的夜班工人与317名非夜班工人进行了比较。
参与者完成了一份关于社会人口统计学和生活方式因素的自填问卷、12项简短健康调查问卷V.2（SF - 12v2）以及匹兹堡睡眠质量指数（PSQI）。应用Baron和Kenny方法、Sobel检验以及带有自抽样的多重中介模型来确定PSQI得分或其组成部分是否介导了夜班工作与HRQoL之间的关联。
夜班工作与睡眠障碍和HRQoL相关。夜班工人在SF - 12的所有八个领域的平均得分显著更低（p<0.001）。与非夜班工人相比，夜班工人更有可能报告睡眠质量较差、入睡潜伏期更长、睡眠时间更短、睡眠障碍和日间功能障碍（p<0.001）。中介分析表明，PSQI全球得分介导了夜班工作与HRQoL之间的关联。“主观睡眠质量”（间接效应=-0.24，SE = 0.14，偏差校正（BC）95% CI -0.58至-0.01）和“睡眠障碍”（间接效应=-0.79，SE = 0.22，BC 95% CI -1.30至-0.42）是夜班工作与身体健康之间关联的中介因素，而“入睡潜伏期”（间接效应=-0.51，SE = 0.21，BC 95% CI -1.02至-0.16）和“日间功能障碍”（间接效应=-1.11，SE = 0.32，BC 95% CI -1.86至-0.58）是与心理健康相关的中介因素。
睡眠质量部分解释了夜班工作与较差的HRQoL之间的关联。组织应将夜班工人的睡眠质量作为改善员工整体健康的首要行动领域。
