Sleep Matters: Sleep as a Buffer of Intersectional Identity-Linked Mental Health Among 52,880 South Korean Adolescents.

Abstract

Background: Adolescent mental health is shaped by multiple factors. This study examined the association between intersectional identity based on gender and family-socioeconomic status (SES) and mental health and whether this association differs by the function of health behaviors (ie, physical activity, screen time, and sleep) among Korean adolescents.

Methods: Nationally representative, cross-sectional, self-reported data from the 2023 Korea Youth Behavior Web-Based Survey (N = 52,880, 12-18 y) were used. Intersectional identity included gender and family SES. Mental health factors included stress, depressive symptoms, and loneliness. Health behaviors included physical activity, recreational screen time, and sleep. Covariates were age, academic performance, and parental educational attainment. Decision tree models, logistic regressions, and moderation analyses were conducted.

Results: Compared with boys, more girls reported high stress (31% vs 44%), depressive symptoms (21% vs 31%), and loneliness (49% vs 63%). A statistically significant interaction between gender × family SES was observed only for loneliness, with girls with low-family-SES reporting the highest likelihood (odds ratio [OR] = 3.60; 95% CI, 3.28-3.95). Physical activity and sleep moderated the association between intersectional identity and loneliness, with sleep showing more salient results. Specifically, not meeting the sleep recommendation was associated with greater loneliness, especially for more marginalized identity groups in a linear manner (boys × mid-family-SES: OR = 1.65; boys × low-family-SES: OR = 2.75; girls × high-family-SES: OR = 2.46; girls × mid-family-SES: OR = 3.01; and girls × low-family-SES: OR = 5.24).

Conclusion: Meeting sleep recommendations may buffer intersectionality-linked loneliness particularly for girls across SES levels and boys with mid-family-SES. Sleep-focused strategies may offer opportunities to address the adolescent loneliness epidemic in Korea.