Does physical activity mediate the relationship between loneliness and mental health in Canadian adolescents?

Abstract

Objectives: Loneliness in adolescents has been consistently increasing over the previous two decades, a trend further exacerbated during to the COVID-19 pandemic. This is particularly concerning considering the links between loneliness and poor mental health. This thesis investigated prospective bidirectional relationships between loneliness and mental health outcomes (anxiety and psychological wellbeing), and additionally, aimed to assess the mediating role of physical activity (PA) within these relationships over a one-year period.

Methods: This study used linked student-level survey data of 20,532 Canadian adolescents from the 9th (2020-2021) and 10th (2021-2022) years of the COMPASS study. Cross-lagged panel mediation models were used to test bidirectional associations between loneliness, anxiety symptoms, psychological wellbeing, and PA. Bootstrapping was used to detect mediation effects of PA in the relationships. Models were stratified by gender, and controlled for student grade, family affluence, province, ethnicity, and school-level clustering.

Results: Gender-diverse/other adolescents reported higher loneliness frequency and anxiety scores, and lower psychological wellbeing, compared to cis-gender adolescents. Bidirectional relationships between loneliness and anxiety, and loneliness and psychological wellbeing were established in the full sample, with associations varying when stratified by gender. PA did not significantly mediate the relationships between loneliness and the mental health outcomes.

Conclusions: Loneliness, anxiety, and psychological wellbeing prospectively and bidirectionally predicted each other, which reinforces current literature that supports loneliness as a risk factor for poor mental health outcomes among adolescents. PA did not mediate these relationships, thus future research should explore novel mediators to help explain the underlying mechanisms in the relationship between loneliness and mental health.