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Journal of the Union of Scientists - Varna. Medicine and Ecology Series

Sleep disorders in shift workers

Alexandra Yankova, Dimitrinka Rosenova Dimitrova, Vladina Dimitrova-Kirilova, Veselinka Nestorova


In the modern industrialized world, 24-hour service has become a necessity for public safety, healthcare and many other services. As a result of this, every one in five workers has working hours outside of the standard 9 AM to 5 PM. Part of them develop shift work disorder (SWD) – a condition caused by the disrupted circadian rhythm, which leads to insomnia and/or excessive sleepiness. These sleep disorders can be the reason for severe health problems, a lowered quality of life, and can hinder work performances.

A survey about the sleep quality and a polysomnographic exam were conducted on 20 patients with shift work (15 doctors, 1 nurse, 1 bartender, 1 labourer and 1 IT specialist). The  age of the participants ranged from 28 to 53 years (M = 36.3) and the work experience on a shift schedule was from 3 to 15 years (M = 11.5). The survey and polysomnography results worsened with increase of years on a shift schedule.


sleep disorders; shift work; insomnia; excessive sleepiness;

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