Effects of Loneliness and Subjective Well-Being on Depression in Female Adolescents: A Longitudinal Moderated Mediation Model of the Parental Relationship

Abstract

Objective Adolescent depressive symptoms are increasingly recognized as a global concern for youth mental health. Female adolescents consistently report higher levels of depressive symptoms than their male counterparts, yet the psychological mechanisms underlying depressive symptoms remain insufficiently understood. Our longitudinal study examined the relationship between loneliness and depressive symptoms in female adolescents and investigated the mediating effect of subjective well-being (SWB) and the moderating influence of the parental relationship. Methods Data were drawn from the Korean Study of Adolescent Health, a longitudinal study on adolescent mental health. The sample included 104 female high school students (mean age=15.33 years) who completed self-report surveys at three time points between April 2022 and July 2023. Measures assessed loneliness, SWB, depressive symptoms, and relationships with mothers and fathers. Mediation and moderated mediation analyses were conducted using SPSS PROCESS (Models 4 and 14), controlling for age, socioeconomic status, and baseline depressive symptoms. Results Mediation analyses indicated that SWB fully mediated the longitudinal association between loneliness and depressive symptoms. Loneliness predicted lower SWB, which subsequently predicted more depressive symptoms. Moderated mediation analysis revealed that maternal, but not paternal, relationship quality significantly moderated the SWB-depressive symptoms link. The indirect effect was significant only among adolescents reporting stronger maternal relationships. Conclusion These findings underscore the importance of SWB in the link between loneliness and depressive symptoms among female adolescents and highlight the protective role of a positive maternal relationship. The results have implications for targeted prevention and intervention strategies to enhance emotional well-being in female adolescents. Psychiatry Investig 2026;23(1):142-153