Longitudinal association between movement behaviours and depressive symptoms among adolescents using compositional...

Area of Science:

• Behavioral science
• Adolescent mental health
• Public health

Background:

• Limited research exists on movement behaviors and mental health using compositional analysis.
• Previous studies often rely on cross-sectional designs, hindering causal inference.

Purpose of the Study:

• To analyze changes in movement behavior composition over time.
• To investigate associations between changes in movement behavior and depressive symptoms.
• To explore how time reallocation between behaviors impacts depressive symptoms.

Main Methods:

• Longitudinal data from 14,620 Canadian high school students (grades 9-12) across two waves.
• Self-reported moderate-to-vigorous physical activity (MVPA), recreational screen time, and sleep duration.
• Compositional data analysis, including pivot coordinates and isotemporal substitution, to assess movement behavior changes and mental health outcomes (CESD-R-10).

Main Results:

• Movement behavior composition significantly changed over time across all subgroups, with increased screen time and decreased MVPA/sleep in younger adolescents and older girls.
• Increased sleep duration relative to other behaviors was linked to lower depressive symptoms.
• Increased screen time relative to other behaviors was associated with higher depressive symptoms.
• Replacing 60 minutes of daily screen time with sleep showed the largest reduction in depressive symptoms.

Conclusions:

• Adolescent sleep duration and screen time are critical factors influencing depressive symptoms.
• Prospective analysis highlights the importance of increasing sleep and reducing screen time for adolescent mental well-being.