Previous studies have revealed the negative consequences of shift work in some individuals, with others better tolerating shift work. The present study investigated clinical implications of shift work-related sleep complaints as a manifestation of shift-work intolerance. Responses were obtained from 923 shift workers and 850 non-shift workers at Seoul National University Bundang Hospital in Seongnam, Korea. The self-reported questionnaires were administered to assess demographic and clinical factors of the participants. Shift work-related sleep complaints were defined as complaints of insomnia or excessive sleepiness related to shift work schedule. Shift workers with sleep complaints suffered from more severe fatigue, depression, anxiety and impaired quality of life compared with both non-shift workers and shift workers without sleep complaints (all p < 0.05). However, we found no substantial difference in clinical symptoms between non-shift workers and shift workers without sleep complaints. The associated factors of shift work-related sleep complaints were frequent night shifts (OR = 1.09, 95% CI = 1.02–1.15), evening chronotype (OR = 0.97, 95% CI = 0.95–0.99) and resilience (OR = 0.98, 95% CI = 0.97–0.99). Shift workers with sleep complaints can suffer from more severe adverse effects of shift work compared to non-shift workers and shift workers without sleep problems. This study suggests that shift-work-related sleep complaints might be a manifestation of shift work intolerance. Therefore, physicians need to recognize and modify the associated factors with sleep complaints alleviating shift work-related health burden.
Chronotype Quality of life Resilience Shift work Sleep complaints
This is a preview of subscription content, log in to check access.
Compliance with ethical standards
Conflict of interest
Hyuk Joo Lee, Kyunglak Son, Young Rong Bang, Hong Joon Jeon, Kiheon Lee, and In-Young Yoon declare that they have no conflict of interest.
This study was approved by the institutional review board of Seoul National University Bundang Hospital.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional review board of Seoul National University Bundang Hospital and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
Informed consent was obtained from all individual participants included in the study.
Costa G. Factors influencing health of workers and tolerance to shift work. Theor Ergon Sci. 2003;4:263–88.CrossRefGoogle Scholar
Salma U, Rao KK. Shift work and depression. Int J Environ Res Dev. 2014;4:417–22.Google Scholar
Kleppa E, Sanne B, Tell GS. Working overtime is associated with anxiety and depression: the Hordaland Health Study. J Occup Environ Med. 2008;50:658–66.CrossRefGoogle Scholar
Schernhammer ES, Laden F, Speizer FE, Willett WC, Hunter DJ, Kawachi I, et al. Night-shift work and risk of colorectal cancer in the nurses’ health study. J Natl Cancer Inst. 2003;4:95:825–8.CrossRefGoogle Scholar
Davis S, Mirick DK, Stevens RG. Night shift work, light at night, and risk of breast cancer. J Natl Cancer Inst. 2001;93:1557–62.CrossRefGoogle Scholar
Asaoka S, Aritake S, Komada Y, Ozaki A, Odagiri Y, Inoue S, et al. Factors associated with shift work disorder in nurses working with rapid-rotation schedules in Japan: the nurses’ sleep health project. Chronobiol Int. 2013;30:628–36.CrossRefGoogle Scholar
Boivin DB, Boudreau P. Impacts of shift work on sleep and circadian rhythms. Pathol Biol. 2014;62:292–301.CrossRefGoogle Scholar
American Academy of Sleep Medicine. The international classification of sleep disorders: diagnostic and coding manual. 2nd ed. Westchester: American Academy of Sleep Medicine; 2005.Google Scholar
Andlauer P, Reinberg A, Fourre L, Battle W, Duverneuil G. Amplitude of the oral-temperature circadian-rhythm and the tolerance to shift work. J Dev Physiol. 1979;75:507–12.Google Scholar
Waage S, Pallesen S, Moen BE, Magerøy N, Flo E, Di Milia L, et al. Predictors of shift work disorder among nurses: a longitudinal study. Sleep Med. 2014;15:1449–55.CrossRefGoogle Scholar
Saksvik IB, Bjorvatn B, Hetland H, Sandal GM, Pallesen S. Individual differences in tolerance to shift work—a systematic review. Sleep Med Rev. 2011;15:221–35.CrossRefGoogle Scholar
Kim JY, Chae CH, Kim YO, Son JS, Kim JH, Kim CW, et al. The relationship between quality of sleep and night shift rotation interval. Ann Occup Environ Med. 2015;27:31.CrossRefGoogle Scholar
Buysse DJ, Reynolds CF III, Monk TH, Berman SR, Kupfer DJ. The Pittsburgh sleep quality index: a new instrument for psychiatric practice and research. Psychiatry Res. 1988;28:193–213.CrossRefGoogle Scholar
Johns MW. A new method for measuring daytime sleepiness: the Epworth Sleepiness Scale. Sleep. 1991;4:540–5.CrossRefGoogle Scholar
Krupp LB, LaRocca NG, Muir-Nash J, Steinberg AD. The fatigue severity scale. Application to patients with multiple sclerosis and systemic lupus erythematosus. Arch Neurol. 1989;46:1121–3.CrossRefGoogle Scholar
Horne JA, Ostberg O. A self-assessment questionnaire to determine morningness-eveningness in human circadian rhythms. Int J Chronobiol. 1976;4:97–110.Google Scholar
Bjelland I, Dahl AA, Haug TT, Neckelmann D. The validity of the Hospital Anxiety and Depression Scale. An updated literature review. J Psychosom Res. 2002;52:69–77.CrossRefGoogle Scholar
Connor KM, Davidson JR. Development of a new resilience scale: the Connor-Davidson Resilience Scale (CD-RISC). Depress Anxiety. 2003;18:76–82.CrossRefGoogle Scholar
World Health Organization Quality Of Life (WHOQOL) Group. Development of the WHOQOL: rationale and current status. Int J Ment Health. 1994;23:24–56.CrossRefGoogle Scholar
Walker RJ, Kribs ZD, Christopher AN, Shewach OR, Wieth MB. Age, the Big Five, and time-of-day preference: a mediational model. Pers Individ Dif. 2016;98:85–90.CrossRefGoogle Scholar
Caruso CC. Negative impacts of shiftwork and long work hours. Rehabil Nurs. 2014;39:16–25.CrossRefGoogle Scholar
Ingre M, Akerstedt T. Effect of accumulated night work during the working lifetime, on subjective health and sleep in monozygotic twins. J Sleep Res. 2004;13:45–8.CrossRefGoogle Scholar
Härmä M, Kecklund G. Shift work and health - how to proceed? Scand J Work Environ Health. 2010;36:81–4.CrossRefGoogle Scholar
Oyane NM, Pallesen S, Moen BE, Akerstedt T, Bjorvatn B. Associations between night work and anxiety, depression, insomnia, sleepiness and fatigue in a sample of Norwegian nurses. PLoS One. 2013;7;8:e70228.CrossRefGoogle Scholar
Geiger-Brown J, Rogers VE, Trinkoff AM, Kane RL, Bausell RB, Scharf SM. Sleep, sleepiness, fatigue, and performance of 12-hour-shift nurses. Chronobiol Int. 2012;29:211–19.CrossRefGoogle Scholar
Boudreau P, Dumont GA, Boivin DB. Circadian adaptation to night shift work influences sleep, performance, mood and the autonomic modulation of the heart. PLoS One. 2013;26:8:e70813.CrossRefGoogle Scholar
Klein DC, Morre RY, Reppert SM, editors. Suprachiasmatic nucleus: the Mind’s clock. New York: Oxford University Press; 1991.Google Scholar
Ogińska H, Pokorski J, Ogiński A. Gender, ageing, and shiftwork intolerance. Ergonomics. 1993;36:161–68.CrossRefGoogle Scholar
Waage S, Moen BE, Pallesen S, Eriksen HR, Ursin H, Akerstedt T, et al. Shift work disorder among oil rig workers in the North Sea. Sleep. 2009;32:558–65.CrossRefGoogle Scholar
Flo E, Pallesen S, Magerøy N, Moen BE, Grønli J, Hilde Nordhus I, et al. Shift work disorder in nurses–assessment, prevalence and related health problems. PLoS One. 2012;7:e33981.CrossRefGoogle Scholar
Di Milia L, Waage S, Pallesen S, Bjorvatn B. Shift work disorder in a random population sample–prevalence and comorbidities. PLoS One. 2013;8:e55306.CrossRefGoogle Scholar
De Terte I, Becker J, Stephens C. An integrated model for understanding and developing resilience in the face of adverse events. J Pac Rim Psychol. 2009:3:20 – 6.Google Scholar
Sallinen M, Kecklund G. Shift work, sleep, and sleepiness—differences between shift schedules and systems. Scand J Work Environ Health. 2010;36:121–33.CrossRefGoogle Scholar