Shift work tolerance and the importance of sleep quality: a study of police officers

Abstract

The aim of this study was to examine how subjective shift work tolerance was related to general health variables, with the expectation of inter-individual differences in the nature of this relation. A total of 740 employees of the Dutch Police force completed a questionnaire, covering seven health-related domains: sleep quality, sleep duration, need for recovery, fatigue, physical health, mental health, and work–life balance. Based on subjective reports of shift work tolerance, participants were classified as intolerant, medium-tolerant, or tolerant workers. Analysis involved group comparisons, regression, and cluster analysis. Eighteen percentage of the shift workers were classified as intolerant. The intolerant and medium-tolerant workers expressed more severe complaints than the tolerant workers, for all seven health-related domains. Shift work tolerance was primarily related to sleep quality and subsequently to need for recovery, fatigue, and work–life balance. No indications were found for systematic inter-individual differences in the nature of this relationship. For all participants equally, the degree of shift work tolerance was related to the severity of health-related complaints. This study highlights the central role of sleep for tolerance to shift work and underlines the need for occupational medicine to take explicit account of sleep.

Keywords:

• shift work tolerance
• sleep
• police
• inter-individual variability

Acknowledgements

The research for this manuscript was carried out within the framework of the University of Amsterdam, supported by ZonMw, under Grant 401000010, awarded to Prof. G.A. Kerkhof. We wish to express our appreciation to the Dutch Police force for their willingness to participate in this study.