The Relationship between Sleep Characteristics and Workplace Accidents

  • Maryam Saraei Center for Research on Occupational Diseases, Tehran University of Medical Sciences, Tehran, Iran
  • Nazanin Izadi Department of Occupational Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
  • Arezu Najafi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Mahdi Mohajeri Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Maryam Maruf Department of Community Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
  • Khosro Sadeghniiat-Haghighi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran
Keywords: Shift work schedule, Occupational accidents, Sleep


Background and Objective: Sleep problems in industries can influence workers’ health. Shift work and its associated sleep problems are quite common among workers in different industries. The aim of this study was to assess sleep quality, insomnia, excessive daytime sleepiness (EDS), and obstructive sleep apnea (OSA) in workers of an automobile factory.

Materials and Methods: This cross-sectional study was conducted during annual periodic examination of workers from a production unit of an automobile factory. A total of 522 workers filled in questionnaires including demographic characteristics, workplace accidents, Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), and STOP-BANG [snoring, tiredness, observed stop of breathing in sleep, blood pressure, body mass index (BMI), age, neck circumference, gender]. T-test and descriptive statistics were used for data analysis.

Results: The participants had mean and standard deviation (SD) age of 37.24 ± 5.73 years. Of 522 participants, 65.3%, 14.4%, and 3.3% had PSQI ≥ 5, ESS ≥ 13, and STOP-BANG ≥ 4, respectively. Higher scores of PSQI and ISI were associated with significant increase of workplace accidents (P = 0.010 and P = 0.004, respectively). Moreover, participants with rotational shift work significantly had more ISI than the ones with fixed shift work.

Conclusion: Poor sleep quality and insomnia were prevalent among studied workers with shift work. Sleep problems also had significant association with workplace accidents. This finding warrants more attention towards shift schedules of the workers and further investigation and management of identified sleep problems.


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How to Cite
Saraei M, Izadi N, Najafi A, Mohajeri M, Maruf M, Sadeghniiat-Haghighi K. The Relationship between Sleep Characteristics and Workplace Accidents. J Sleep Sci. 3(1-2):30-35.
Original Article(s)