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

ABSTRACT

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