Detrimental effects of variable work shifts on quality of sleep, general health and work performance

The aim of this study was to explore the detrimental effects of working a varying pattern of 8-hour shifts on quality of sleep, general health and work performance. The Arabic version of the Pittsburgh Sleep Quality Index [PSQI]and 2 self-administered questionnaires were used to assess quality of sleep, work performance and general health in a sample of 200 males on a schedule of varying 8-hour shifts at the Kuwait Oil Company. A matched sample of an equal number of workers on a fixed daytime shift as a control group was enrolled in the study. Compared with men working on a straight daytime shift schedule, those working on 8-hour variable shifts exhibited higher rates of heavy smoking [p < 0.003], coffee/tea consumption [p < 0.0001], constipation [p < 0.002], job stress [p < 0.0001] and poor sexual performance [p < 0.0001]. Variable-shift workers reported persistent sleep disturbances in 3 dimensions of the global score of the PSQI [p < 0.0001]. They also had significantly more complaints of fatigue [p < 0.005], poor level of work performance [p < 0.005] and loss of concentration [p < 0.005]. Shift workers were significantly more prone to making errors and having accidents at work, and were more likely to report absence from work than the controls [p < 0.0001 and p < 0.005, respectively]. These results suggest that the majority of workers on an 8-hour variable-shift schedule experienced various health problems, poor quality of sleep and an increased risk for errors and accidents at work as compared with those workers on a straight daytime shift schedule. There is a need to compare potential benefits of an alternative work shift schedule

Effect of 8-hour variable shift-work schedules on quality of sleep, work performance and general health

Data collected by combined self-administered questionnaires from 200 Kuwaiti males on variable shift-work and an equal number of males on straight one-shift-work at the Kuwait Oil Company [KOC] were studied over a 9-month period. Compared to men working a non-variable work schedule, those working variable shifts exhibited higher [P<0.0001] rates of heavy smoking, coffee/tea consumption, job stress and emotional problems. Variable shift-workers reported a significantly [P<0.0001] more persistent sleep disturbance of all dimensions, digestive complaints, decreased work performance and disruptive social life than did straight one-shift-workers. Forty-One percent complained of fatigue and 34% of poor concentration. They were also more prone to errors and accidents at work. The underlying psychophysiological factors are discussed. The need for a better occupational health system is emphasized