“There’s still an assumption that if you do night work, you adjust at some stage,” said researcher Bärbel Finkenstädt. “But you don’t. We saw that most workers compensate in terms of quantity of sleep, but not in terms of quality during the work time.”
Risks of shift work
The researchers conducted their study on two groups of hospital workers – one group worked the night shift for three or more nights per week, and the other group alternated between morning and afternoon shifts. All participants wore devices that tracked their sleep, circadian rhythms, and surface temperature.
After analyzing the results from the wearable devices, the team identified significant differences between night shift workers and day shift workers. Night shift workers had poorer sleep quality, and nearly 50% of them experienced disruptions to their natural circadian rhythms.
These findings held up regardless of how long the participants worked night shifts. Participants who had been on that assignment for years were experiencing poorer sleep, and the longer they did night work, the worse their outcomes were.
“Nearly 20% of the night workers could not even adjust their circadian rhythms during their free time, with the severity of impairment tending to increase with the number of years in night work,” said researcher Francis Lévi. “The telemonitoring technology, and analysis methods we have set up make it now possible to objectively evaluate circadian and sleep health in night workers in real time, and design prevention measures for individual workers whenever necessary.”
While working nights is unavoidable in many industries, the researchers say it’s important that efforts are taken to ensure that workers are prioritizing their health as best as they can.
“I think there’s a misunderstanding that night shift work is just an inconvenience, whereas it can be linked to serious health risks,” said researcher Julia Brettschneider. “We can’t avoid shift work for many professions, like health care workers, so we should be thinking about what can be done in terms of real-world adjustments to improve working conditions and schedules of shift workers. A better understanding of the biological mechanisms helps to find answers to this question.”