Hazards of Rotating Night Shift Work in Emergency Medicine: A Multiple Health System Observational Study Using Apple Watch

Emergency department (ED) physicians work rotating night shift schedules, which may disrupt sleep and contribute to burnout. The objective of this study is to investigate sleep quality and wellbeing among ED physicians.

REST-EM is a 90-day observational study of ED physicians recruited nationally using professional networks. Participants completed validated surveys including the Munich Chronotype Questionnaire (MCTQ), Consensus Sleep Dairy (CSD-M), and Karolinska Sleepiness Scale (KSS). Participants were asked to complete three randomized 7-day periods where they wore an Apple Watch nearly 24/7. We obtained objective sleep data via Apple’s Sleep Analysis along with participant-completed CSD-M. We used descriptive analysis to report preliminary results on participant demographics, survey results, and sleep data completeness.

From March-December 2025, we enrolled 236 participants. Most participants were between ages 30-39 (n=124) and 40-49 (n=105). A total of N=48 participants were included in this analysis. Of those, 43.8% identified as female, and participants had an average of 5.97 years in practice. 46 participants (95.8%) completed at least one complete 7-day window of sleep data collection. Following evening shifts, sleep midpoint was between 02:45 and 04:30 for the middle 50% of participants. Mean (SD) self-reported sleep quality score was 3.4 (0.9), with 72% of participants reporting scores below the threshold (<3) for “poor” sleep on at least one occasion. KSS scores across days had a mean (SD) of 4.7 (2.1). Between shift types, KSS scores indicated greater sleepiness following night shifts, with a mean (SD) score of 5.6 (2.2).

These findings suggest substantial variation in chronotype and sleep quality among ED physicians, with the majority reporting poor sleep quality and increased sleepiness on days following night shifts. Continued data collection and future analysis will examine the relationship between chronotype misalignment, objective and subjective sleep data, and physician burnout.