Study: Shift workers do not adjust to night shift

Editor's Note

This study from the UK and France finds that sleep quality and circadian rhythms in night shift workers were poorer than in those who worked day shifts, even if they had been working the night shift for years.

The analysis compares 63 night shift workers, working three or more nights of 10 hours each per week, and 77 day shift workers alternating morning and afternoon shifts.

Even though both groups had similar rest amounts, night shift workers had less than half the median regularity and quality of sleep of day shift workers. A total of 48% of night shift workers also displayed a disrupted circadian temperature rhythm, compared to 70% of day shift workers.

In addition, poor probability of remaining at rest was associated with night shift work on both work and free days.

The number of years of night work predicted poor regularity and quality of sleep together with shift type, age, and morningness or eveningness orientation on workdays and free days, the researchers note.