Actigraphic sleep dimensions and associations with academic functioning among adolescents.

STUDY OBJECTIVES: There is mixed evidence regarding associations of sleep duration with academic functioning in adolescents and a lack of research on other sleep dimensions, particularly using objective sleep measures. We examined associations of multiple actigraphic sleep dimensions with academic functioning among adolescents.

METHODS: Data were from the sleep sub-study of the age 15 wave of the Future of Families and Child Wellbeing Study (n=774-782), a national, diverse sample of teens. Adolescents wore wrist-actigraphs for ~1 week and completed a survey reporting grades and school-related problems. Regression models assessed whether average sleep duration, timing, maintenance efficiency, and SD-variability were associated with self-reported academic functioning in cross-sectional analyses adjusted for demographic characteristics, depressive symptoms, and anxious symptoms.

RESULTS: Later sleep timing (hrs) and greater sleep variability (SD-hrs) were associated with poorer academic outcomes, including sleep onset variability with higher odds of receiving a D or lower (OR=1.29), sleep onset (β=-.07), sleep offset (β=-.08), and sleep duration variability (β=-.08) with fewer A grades, sleep offset with lower GPA (β=-.07), sleep offset (OR=1.11), sleep duration variability (OR=1.31), and sleep onset variability (OR=1.42) with higher odds of being suspended or expelled in the past two years, and sleep duration variability with greater trouble at school (β=.13). Sleep duration, sleep maintenance efficiency, and sleep regularity index were not associated with academic functioning.

CONCLUSION: Later sleep timing and greater sleep variability are risk factors for certain academic problems among adolescents. Promoting sufficient, regular sleep timing across the week may improve adolescent academic functioning.