An irregular sleep schedule can increase a person’s risk of depression over the long term as much as getting fewer hours of sleep overall, or staying up late most nights, a new study suggests.
Even when it comes to just their mood the next day, people whose waking time varies from day to day may find themselves in as much of a foul mood as those who stayed up extra late the night before, or got up extra early that morning, the study shows.
The study, conducted by a team from Michigan Medicine, the University of Michigan’s academic medical center, uses data from direct measurements of the sleep and mood of more than 2,100 early-career physicians over one year. It’s published in npj Digital Medicine.