Irregular sleep and late bedtimes associated with worse grades for high school students

Irregular sleep and late bedtimes are linked to worse grades and more school-related behavioral problems among teens, suggests a recent study. The authors stated that interventions to promote regular sleep schedules may boost adolescents' academic performance.

The study, conducted by Gina Marie Mathew, Ph.D., and Lauren Hale, Ph.D., of Stony Brook University and colleagues, appears in Sleep.

Researchers analyzed data from nearly 800 adolescents participating in a larger study. Participants provided information on grades and school-related behavioral issues. They also wore a wrist accelerometer (a device that records the wearer's movements) for a week so that study staff could estimate their sleep patterns.

Participants with more variable bedtimes had a greater chance of receiving a D or lower during the last grading period compared to those with more consistent bedtimes. Adolescents who went to bed later got up later, or varied the number of hours they slept per night had fewer classes in which they received an A.

Adolescents were more likely to be suspended or expelled in the last two years if they got up later, varied the number of hours they slept each night, or if they varied the time they went to bed each night.

The authors theorized that delayed bedtimes could result in late school arrivals, which could affect learning and behavior. In addition, many adolescents are biologically inclined to later hours, which conflict with early school start times.