A Longitudinal Study of Insomnia, Daytime Sleepiness, and Academic Performance in Chinese Adolescents

Background Longitudinal data on the associations between sleep disturbances, daytime sleepiness, and daily functioning are limited in the general adolescent population. This study examined the cross-sectional and longitudinal associations between insomnia, excessive daytime sleepiness (EDS), and subject-specific academic performance in a large sample of Chinese adolescents. Method Data were derived from the Shandong Adolescent Behavior and Health Cohort (n = 7,072) study. A self-administered questionnaire was used to assess insomnia, EDS, academic performance (overall, Chinese, mathematics, and English), behavioral and emotional problems, and family demographics. The cross-sectional analysis was conducted with baseline data while the longitudinal analysis was conducted with both baseline and 1-year follow-up data. Logistic regression analyses and mediation models were performed to examine the associations between insomnia, EDS, and academic performance. Results Logistic regression analyses revealed that insomnia and EDS had significant cross-sectional associations with overall performance and mathematics performance after controlling for age, gender, ever smoking, ever alcohol drinking, frequent snore, sleep duration, chronic disease, anxious/depressive symptoms, parents' education, parents' occupation, and family economic status. Both insomnia (OR = 1.20, 95% CI: 1.00-1.45) and EDS (OR = 1.22, 95% CI: 1.03-1.45) at baseline were significantly associated with poor mathematics performance 1 year later. The effect of insomnia at baseline on poor academic performance 1 year later was mediated by EDS except for the Chinese subject after controlling for the covariates. Conclusions Insomnia and daytime sleepiness are significantly associated with poor academic performance, particularly in mathematics. EDS mediates the association between insomnia and poor academic performance. Further research is warranted to investigate the effects of sleep disturbance and daytime sleepiness on the learning process and performance across academic subjects.