Changes in Sleep Duration and Timing During the Middle-to-High School Transition.

Abstract Purpose The purpose of the study was to quantify changes in sleep during the middle-to-high school transition and determine if changes in sleep differ by sociodemographic characteristics. Methods Adolescents were enrolled in eighth grade and followed into ninth grade (N = 110; 2,470 nights observed). The outcomes were actigraphy-estimated sleep duration, sleep onset, sleep offset, and sleep sufficiency (≥8 hours of sleep). The exposures were school grade (eighth or ninth), school night status (school or nonschool), sex (female or male), and race (white, black, or other). Results On school nights, sleep duration declined by 25.8 minutes per night (p Conclusions Insufficient sleep is highly prevalent, especially on school nights and among male and black adolescents, and this problem worsens with the transition to high school.