Late chronotype and high social jetlag are associated with burnout in evening-shift workers: Assessment using the Chinese-version MCTQshift

Wan-Ju Cheng; Liang-Wen Hang

doi:10.1080/07420528.2018.1439500

Late chronotype and high social jetlag are associated with burnout in evening-shift workers: Assessment using the Chinese-version MCTQ^shift

Chronobiol Int. 2018 Jul;35(7):910-919. doi: 10.1080/07420528.2018.1439500. Epub 2018 Apr 16.

Authors

Wan-Ju Cheng^{1

2}, Liang-Wen Hang^{3

4}

Affiliations

¹ a Department of Psychiatry , China Medical University Hospital , Taichung , Taiwan.
² b Department of Public Health , China Medical University , Taichung , Taiwan.
³ c Department of Respiratory Therapy , College of Health Care, China Medical University , Taichung , Taiwan.
⁴ d Sleep Medicine Center, Department of Pulmonary and Critical Care Medicine , China Medical University Hospital , Taichung , Taiwan.

PMID: 29658812
DOI: 10.1080/07420528.2018.1439500

Abstract

Chronotypes are associated with shift work tolerance and sleep in shift workers, and sleep mediates the impact of shift work on mental health. However, the role of chronotype in the association between shift work and mental health has not been clarified. In this study, we aimed to examine the association between chronotype and burnout in shift workers, using the validated Munich ChronoType Questionnaire for shift workers (MCTQ^shift). A total of 288 shift workers with irregular shift frequencies were recruited and completed the Chinese-version MCTQ^shift and the Morningness-Eveningness Questionnaire (MEQ). Chronotypes were assessed by the calculation of corrected mid-sleep time (MSF_SC) from mid-sleep time on free days (MSF) based on their exact shift schedules. Another 26 evening-shift nurses were monitored with actigraphy for at least two consecutive evening shifts and the following two free days. Burnout was evaluated using the Copenhagen Burnout Inventory. We found that MSF^E_SC, MSF^E and mid-sleep time on workdays (MSW^E) had normal distributions and correlated significantly with MEQ scores (r = - 0.47, -0.45 and -0.47, respectively; all p < 0.001). MSW was more closely correlated with actigraphy-derived mid-sleep time on the free day before workdays than that on workdays (r = 0.61 and 0.48, respectively, p < 0.05). Sleep duration was significantly longer on workdays among evening-shift workers who slept late on workdays than those who slept early (β = 0.59, p < 0.001). After demographic and work characteristics were adjusted for in linear regression models, late chronotype and high social jetlag were associated with burnout scores in evening-shift workers. In conclusion, the Chinese-version MCTQ^shift is a valid tool for chronotype assessment. Interventions to improve sleep in shift workers should be tailored to chronotype due to variations in sleep behavior. Late chronotype may be an inherent feature of mental health problems, because the association with burnout was significant in both day workers in previous studies and shift workers.

Keywords: Shift work; burnout; chronotype; sleep.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Asian People
Burnout, Psychological / physiopathology*
Circadian Rhythm / physiology*
Female
Humans
Male
Middle Aged
Sleep / physiology*
Sleep Wake Disorders / physiopathology*
Surveys and Questionnaires
Time Factors
Wakefulness / physiology