The body clock and the bedside: A nurse scientist investigates shiftwork

Kathryn McAuliffe wants to know if shiftwork affects a person’s intention to stay at a job. McAuliffe is a doctoral candidate in Associate Professor Andrew McHill’s Sleep, Chronobiology and Health Lab at OHSU where McHill is an affiliate faculty member at the Oregon Institute of Occupational Health Scineces. There, McAuliffe is building a scientific case for something she knows well—the impact of working nights as a nurse, and the calculation so many healthcare workers make: is it worth it to stay?

McAuliffe earned a Master of Science in Nursing from Johns Hopkins University and began a career as a nurse at the University of Michigan’s Michigan Medicine where she was confronted with both the toll of working nights as a nurse and the COVID pandemic. McAuliffe soon left her nursing position for a role in clinical research in Detroit. That work eventually brought McAuliffe back home to Oregon and Associate Professor McHill’s laboratory.

McAuliffe is the lead author of a recent publication in SLEEP Advances (2025) that mapped sleep insufficiency against life expectance across all 3,143 US counties using five years of the Center for Disease Control's Behavioral Risk Factor Surveillance System data. The research team found that even when controlling for factors such as smoking, physical inactivity, food insecurity and other mortality predictors, counties where residents were sleeping less than seven hours a night had lower county-level life expectancy. The research team found that only cigarette smoking had a greater impact on life expectancy than sleep.

“I’m concerned that people may not realize how drastically important sleep health is to their longevity,” McAuliffe said. “We’d all do a lot better if we slept more and slept better.”

In an abstract detailing a secondary analysis of data from McHill's lab tracking newly hired shiftworkers transitioning to early-morning shifts—McAuliffe found that workers whose actual sleep onset was too close to their body's natural sleep preparation signal—meaning their internal clock hadn't yet caught up to their new schedule—were significantly more likely to say they were thinking about quitting. Workers who stayed on day shifts showed no such pattern.

McAuliffe’s recently approved dissertation study will build on her personal experience and findings from her secondary analysis. The study will examine if and how circadian misalignment—the degree of mismatch between a person’s internal body clock and when they go to sleep—associated with shiftwork influences a person’s decision to leave the job. McAuliffe will follow newly hired nurses at OHSU through their first year of shiftwork, measuring sleep quality, circadian alignment, social support, burnout, and turnover intention—and interviewing nurses directly about their reasons for wanting to leave.

If circadian misalignment proves a measurable driver of nurse turnover, it becomes a potential target for intervention. For McAuliffe, that possibility is both a scientific question and a deeply personal one.