News Release

Research aims to improve night-shift workers' sleep

Job performance for older employees critical as labor force ages

Grant and Award Announcement

University of Massachusetts Lowell

LOWELL, Mass. - A UMass Lowell expert on sleep is examining strategies to help night-shift workers get more restful shuteye, critical to preventing ill health effects.

"By next year, a quarter of the workforce will be over 55 years old," said Yuan Zhang, an associate professor in UMass Lowell's Solomont School of Nursing. "Inadequate sleep is one of the most difficult problems facing American night workers. Given our increasing understanding of how sleep deficiency contributes to adverse performance, health and safety, finding solutions to this issue has never been more important."

Good sleep at any age is essential to overall health. But for 3 million older people in the U.S. who work at night, sound rest is hard to come by. Sleep disruption can lead to depression, cardiovascular diseases and accidents on the job or at home, according to Zhang, who lives in Westford.

She is partnering on a four-year, $1.7 million research project funded by the National Institute of Aging to examine how different sleep schedules for night-shift employees age 50 to 65 may help them be more productive on the job.

Most employees who work the overnight shift sleep in the morning when they come home, which means they wake up eight or more hours before their next shift. That routine not only has them working when their biological clock wants their body to sleep, Zhang said, but they have been awake longer before starting work.

But an alternative schedule may be more beneficial for these workers, according to Zhang. To find out, the research team - which includes UMass Lowell nursing majors Rachel Nunes of Foxborough and Janine Reidy of Westwood - will recruit 75 study participants who work the overnight shift in the health-care industry to test several sleep patterns for two weeks. While one group of workers will follow their usual routine of sleeping after the night shift, two other groups will sleep continuously for eight hours, either starting in the early afternoon or as they prefer.

The researchers will also survey a group of 1,000 night-shift workers and conduct focus groups with a subgroup of the participants to help determine whether the proposed sleep schedules are acceptable and beneficial in real-world conditions.

In her role, Zhang will lead the recruitment of health-care workers to the study, assist with the survey development and study's data collection, facilitate the focus groups and disseminate the study findings to health-care workers. At UMass Lowell, she teaches nursing courses including nursing research at both the undergraduate and graduate levels, proper medication dosing and senior clinical seminars.

Jeanne Duffy, a researcher in the Division of Sleep and Circadian Disorders at Brigham and Women's Hospital in Boston and associate professor at Harvard Medical School, is leading the research, which builds upon her earlier work that found participants were more alert, performed better at night and had lower levels of cortisol - a hormone that is released in the body when an individual is under stress - in their system when they spent eight hours in bed after attempting to sleep beginning in the early afternoon, Zhang said.

"While a number of strategies to improve sleep and alertness in shift workers have been tested, few studies have focused on a sleep-pattern change for older adults, who are becoming a significant portion of the overall workforce," Zhang said of the new project.


Night-shift workers interested in participating in the study should contact 617-525-8904 or to learn more.

UMass Lowell is a national research university located on a high-energy campus in the heart of a global community. The university offers its more than 18,000 students bachelor's, master's and doctoral degrees in business, education, engineering, fine arts, health, humanities, sciences and social sciences. UMass Lowell delivers high-quality educational programs, vigorous hands-on learning and personal attention from leading faculty and staff, all of which prepare graduates to be leaders in their communities and around the globe.


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