Is Loneliness a Mechanism Linking Sleep Disturbance with Symptoms of Generalised Anxiety, Social Anxiety, Depression, and Eating Disorders in Adolescence? Findings From a 6-Year Longitudinal Study

Study Objectives: Sleep disturbance and loneliness have both emerged as potentially important risk factors for generalised anxiety, social anxiety, depression and eating disorders in adolescents. Further, theories suggest sleep disturbance may increase risk for these social-emotional disorders, in-part, by increasing loneliness. This study investigated whether loneliness is a mediating factor linking sleep disturbance with symptoms of social-emotional disorders across the course of adolescence. Methods: As part of the wider Risks to Adolescent Wellbeing Project, these constructs were assessed longitudinally in a cohort of 528 adolescents over seven annual waves of data collection, spanning ages 11 to 17. Sleep (morningness/eveningness preference, school night sleep duration, daytime sleepiness), loneliness and symptoms of generalised anxiety, social anxiety, depression and eating disorders were measured via self-report questionnaires. Results: Cross-lagged panel models showed sleep disturbance predicted worse symptoms of generalised and social anxiety, depression, and eating disorders over time. Higher loneliness also predicted worse symptoms of social anxiety, depression and eating disorders. Loneliness significantly mediated the relationship between sleep disturbance and social anxiety and depression. Yet, generalised anxiety, social anxiety and depression also mediated the association between sleep and loneliness. These results highlight sleep as an important longitudinal predictor, as well as possible bi-directionality between loneliness and social-emotional distress. Conclusions: Results partially support theories that have proposed loneliness as a mechanism linking sleep with depression and anxiety in young people. Clinically, when trying to prevent or treat social-emotional disorders in adolescence, results suggest that it may be useful to target both sleep disturbance and loneliness. This paper is part of the Sleep and Circadian Mechanisms in Mental Health Collection.