Social jetlag as a predictor of depressive symptoms among Japanese adolescents: Evidence from the Adolescent Sleep Health Epidemiological Cohort

Sleep Health. 2023 Oct;9(5):638-644. doi: 10.1016/j.sleh.2023.06.005. Epub 2023 Jul 14.

Abstract

Objectives: Social jetlag, a circadian misalignment, has been associated with depressive symptoms in the general and working populations. However, evidence for this association in adolescents is inconsistent. This cross-sectional study aimed to investigate the association between social jetlag and depressive symptoms among Japanese adolescents and to evaluate differences by sex.

Methods: The participants were 1493 students (13.6 ± 0.9years, 52.4% girls) from five junior high schools. Questionnaires, including demographic information and the Munich ChronoType Questionnaire, were distributed. Social jetlag was defined as the difference between midsleep on weekdays and weekends, and was categorized as <0 hour (negative), 0 to <1 hour, 1 to <2 hours, or ≥2 hours. Depressive symptoms were assessed using the Birleson Depression Self-Rating Scale for Children. Multivariate logistic regression was used to estimate the odds ratio with adjustments for potential confounders, such as puberty- and lifestyle-related factors.

Results: The distribution of students with <0 hour, 0 to <1 hour, 1 to <2 hours, and ≥2 hours of social jetlag was 9.4%, 37.0%, 33.3%, and 20.4%, respectively. The multivariate-adjusted model revealed that social jetlag ≥2 hours and <0 hour were associated with an elevated risk of depressive symptoms among girls and boys, respectively. These associations were nonlinear for both sexes in restricted cubic spline analyses.

Conclusions: Social jetlag is associated with depressive symptoms among adolescents. Specifically, the risk of depressive symptoms increased with positive social jetlag scores for girls and negative social jetlag scores for boys.

Keywords: Adolescents; Cross-sectional study; Depressive symptoms; Japanese; Restricted cubic spline regression analysis; Social jetlag.