TUESDAY, Feb. 16, 2016 (HealthDay News) -- Parents who struggle to get their teens to bed at a decent hour may get some help from a new study that found sleep was closely linked to school achievement.
High school students who went to sleep by 11 p.m. Monday through Friday got better grades, the research showed.
On the flip side, the less sleep teens got, the lower their grades were on average, the researchers said.
"Our findings suggest that going to bed earlier, and encouraging similar bed and sleeping times during the week, are important for academic performance," study first author Mari Hysing, a psychology specialist at Uni Research in Bergen, Norway, said in a news release from the organization.
Although the study found a link between sleep and school performance, it didn't prove a cause-and-effect relationship.
The researchers looked at data from almost 7,800 students aged 16 to 19 from a large population-based study conducted in Norway in 2012. The investigators used the students' overall grade point average (GPA) to assess their school performance.
The study found that those who went to bed between 10 p.m. and 11 p.m. on weekdays earned the best grades, on average. Staying up much later was associated with lower GPAs, the study authors said.
And even those who slept well during the week but stayed up late on the weekends saw their school work suffer, the researchers said.
After considering other social and demographic factors, the study authors reported that the likelihood of poor school performance was greatest among the teens who didn't get enough sleep. This link remained significant even after missed school days were taken into account.
"Academic performance is an important marker for future work affiliation and health. Future studies should investigate further how the association between sleep and school impacts upon future educational status and work affiliation," Hysing and colleagues wrote.
The study was published online recently in the Journal of Sleep Research.
The American Academy of Pediatrics has more about bedtime routines for school-aged children.