Presented at the Doris Duke Clinical Research Fellows Meeting, Chapel Hill, NC, May 2009; and the American College of Emergency Physicians Scientific Assembly, Boston, MA, October 2009.
Original Research Contribution
The Relationship Between Shift Work, Sleep, and Cognition in Career Emergency Physicians
Version of Record online: 5 JAN 2012
© 2012 by the Society for Academic Emergency Medicine
Academic Emergency Medicine
Volume 19, Issue 1, pages 85–91, January 2012
How to Cite
Machi, M. S., Staum, M., Callaway, C. W., Moore, C., Jeong, K., Suyama, J., Patterson, P. D. and Hostler, D. (2012), The Relationship Between Shift Work, Sleep, and Cognition in Career Emergency Physicians. Academic Emergency Medicine, 19: 85–91. doi: 10.1111/j.1553-2712.2011.01254.x
Funded by the Doris Duke Clinical Research Fellowship Program.
PDP—The project described was supported by Award Number KL2 RR024154 from the National Center for Research Resources. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health. No other disclosures. CWC—supported in part by an NHLBI grant U01HL077871. CM—NIH CTSA award funded the support for the statistical analysis. No other disclosures. The rest of the authors have no disclosures or conflicts of interest to report.
Supervising Editor: Jacob Ufberg, MD.
- Issue online: 17 JAN 2012
- Version of Record online: 5 JAN 2012
- Received March 22, 2011; revision received July 22, 2011; accepted July 28, 2011.
ACADEMIC EMERGENCY MEDICINE 2012; 19:85–91 © 2012 by the Society for Academic Emergency Medicine
Objectives: The 24-hour physician coverage of the emergency department (ED) requires shift work, which can result in desynchronosis and cognitive decline. We measured changes in cognition and sleep disturbance in attending emergency physicians (EPs) before and after day and overnight shifts.
Methods: Thirteen EPs were tested before and after day and overnight shifts using the Paced Auditory Serial Addition Test (PASAT), the University of Southern California Repeatable Episodic Memory Test (REMT), the Trail Making Test (TMT), and the Stroop Color-Word Test. Sleep quality and fatigue were assessed using the Pittsburgh Sleep Quality Index (PSQI) and Chalder Fatigue Questionnaire (CFQ). Saliva samples were collected from each physician immediately before and after day shifts and night shifts for neurohormonal assays.
Results: Significantly fewer words were recalled on the REMT after both day (−2.4, 95% confidence interval [CI] = −4.4 to −0.4) and overnight shifts (−4.6, 95% CI = −6.4 to −2.8). There was a significant postshift increase in words recalled from the last third of the REMT list after overnight shifts (6.6, 95% CI = 2.8 to 10.4). Sleep quality was worse in EPs (mean PSQI = 4.8, SD ± 2.5) compared to the normal population, with 31% of subjects reporting poor sleep quality. Postshift fatigue was correlated with the perceived difficulty of the shift. Salivary cortisol and melatonin demonstrated diurnal variation consistent with normal circadian rhythms. Morning cortisol peak was decreased or delayed in samples from physicians after a night shift.
Conclusions: These data indicate that short-term memory appears to decline after day and overnight shifts and confirms the high incidence of disturbed sleep in this population.