Excessive Screen Time is Associated with Mental Health Problems and ADHD in US Children and Adolescents: Physical Activity and Sleep as Parallel Mediators

To examine associations between screen time and anxiety, depression, behavior or conduct problems, and ADHD among children and adolescents during the pandemic, and to assess whether physical activity, sleep duration, and bedtime regularity mediate these associations. Data from 50231 US children and adolescents aged 6 to 17 years in the 2020 to 2021 National Survey of Childrens Health were analyzed. Exact natural effect models and structural equation modeling assessed mediation by physical activity, short sleep duration, and irregular bedtime. We found that daily screen time equal or more than 4 hours was linked to higher risks of anxiety (aOR = 1.45, 95% CI 1.32, 1.58), depression (aOR = 1.65, 95% CI 1.41, 1.93), behavior or conduct problems (aOR = 1.17, 95% CI 1.05, 1.30), and ADHD (aOR = 1.21, 95% CI 1.11, 1.33). Physical activity accounted for 30.2% to 39.3% of the association, irregular bedtime for 18.2% to 25.7%, and short sleep duration for 2.77% to 7.34%. Excessive screen time was associated with poorer mental health and ADHD, partly explained by reduced physical activity, irregular bedtime, and insufficient sleep. Interventions should promote physical activity, regular sleep routines, and adequate sleep duration to effectively mitigate mental health issues and ADHD among children and adolescents.