Digital Media, Genetics, and Risk for ADHD Symptoms in Children: A Longitudinal Study

BACKGROUND Children spend significant amounts of time using digital media (DM), and longer exposure may increase attention-deficit/hyperactivity disorder (ADHD)-related symptoms, although findings are mixed. We investigated longitudinal association between different types of DM use and ADHD-related symptoms in school-aged children, accounting for genetic predisposition and socioeconomic status. METHODS This study included children from the Adolescent Brain Cognitive Development Study, and these children were followed annually for 4 years. Estimated time spent on social media, video games, and television/videos was self-reported using Youth Screen Time Survey. ADHD-related symptoms were assessed at each visit with the parent-reported Child Behavior Checklist. Genetic predisposition was estimated using a polygenic risk score for ADHD (PGS-ADHD). RESULTS The study included 8324 children (53% boys; mean age: 9.9 years). On average, children spent 2.3 hours/d watching television/videos, 1.4 hours/d on social media, and 1.5 hours/d playing video games. Average social media use was associated with increased inattention symptoms over time (β [SE], 0.03 [0.01]; P < .001), with a cumulative 4-year effect of β = 0.15 (SE, 0.03; P < .001). No associations were found between playing video games or watching television/videos and ADHD-related symptoms. The association between social media use and inattention symptoms was not moderated by sex, ADHD diagnosis, PGS-ADHD, or ADHD medication status. Inattention symptoms were not associated with increased social media use over time. CONCLUSION Social media use was associated with an increase in inattention symptoms in children over time. Although the observed effect size was small, it could have significant consequences if behavior changes occur at the population level.