Prospective Association of Sedentary Behavior With Psychological Distress Among Adolescents.

Purpose: To analyze the associations of different types and contexts of sedentary behavior during mid-adolescence (14 years) with later psychological distress (at 17 years).

Methods: The data include 3,675 adolescents from the Millennium Cohort Study. During mid-adolescence, participants completed a time-use diary reporting time in different sedentary activities, which were also categorized into broader contexts (i.e., Leisure-based screen-time, leisure-based nonscreen time, and educational sedentary behavior). Participants reported psychological distress at the 17-year wave, through the Kessler scale. Gender, parent's education, family net income, parent's psychological distress, body mass index, physical activity, total sedentary time (time-use diary), depressive symptoms, and bullying victimization, all assessed during mid-adolescence, were used as covariates. Interaction terms were included to assess the effect-modification of gender.

Results: Increasing 1 hour of playing video games, reading for leisure and total leisure-based screen-time was prospectively associated with a 3% (risk ratio: 1.03; 1.01-1.04), 5% (1.05; 1.01-1.08) and 2% (1.02; 1.01-1.03) higher psychological distress respectively. Only the groups with more than 180 min/day of leisure-based screen time were associated with higher psychological distress (180-300 min/day: 1.08; 95% confidence interval: 1.00-1.17. 300+ min/d: 1.13; 95% confidence interval: 1.03-1.23). Similarly, only higher levels of reading for leisure and playing video games were associated with higher psychological distress. Moderate (60-119 min) durations of homework (0.92; 0.86-0.99) and higher durations attending class (0.94; 0.89-0.99) were associated with lower psychological distress. There were only minor gender interactions.

Discussion: Among adolescents, the association between sedentary behavior and psychological distress is domain-dependent. Future interventions should focus on reducing leisure-time screen-based behaviors to less than 3 h/day.