Problematic Social Media Use and Attention-Deficit/Hyperactivity Disorder Symptoms in Adolescents.

Importance: Given shared processes in attentional control, impulsivity, and reward sensitivity, problematic social media use (PSMU) may be associated with attention-deficit/hyperactivity disorder (ADHD) symptoms. Yet most evidence has been from cross-sectional studies; multiyear prospective, within-person studies on an association of PSMU with ADHD symptoms are lacking. Objectives: To estimate bidirectional, within-person associations between PSMU and ADHD symptoms across 5 annual assessments, and to test variation by sex. Design, Setting, and Participants: This prospective cohort study used data from 5 annual assessments (year 2 [2017-2019] through year 6 [2021-2023]) of the Adolescent Brain Cognitive Development Study, a population-based cohort that enrolled youths aged 9 to 10 years from 21 US sites in year 1 (2016-2018). Participants had data on ADHD symptoms or PSMU at 1 or more waves between year 2 and year 6. Data analysis was performed between July and September 2025. Exposure: Youth-reported PSMU measured using the Social Media Addiction Questionnaire. Main Outcomes and Measures: Parent-reported ADHD symptoms (measured using the ADHD Problems subscale of the Child Behavior Checklist) at each wave. Random-intercept cross-lagged panel models were used to separate stable between-person differences from within-person variation and to estimate concurrent and lagged within-person associations between PSMU and ADHD symptoms across waves. Results: The analytic sample consisted of 11 286 youths with a mean (SD) age at year 2 of 12.1 (0.67) years; 5918 (52.4%) were male. At the within-person level, years in which youths reported higher-than-usual PSMU were followed by elevations in parent-reported ADHD symptoms (year 4 to year 5: β  = 0.08 [95% CI, 0.03-0.12], P < .001; year 5 to year 6: β = 0.08 [95% CI, 0.03-0.13], P = .001). ADHD symptoms were also associated with higher PSMU from year 4 to year 5 (β = 0.04 [95% CI, 0.01-0.07]; P = .02). Tests of moderation indicated that the prospective association between PSMU and ADHD symptoms was higher in magnitude for males than for females (change in χ216 = 31.7; P = .01). Conclusions and Relevance: This cohort study of US youths found that year-to-year elevations in self-reported PSMU were directly associated with ADHD symptoms during mid-adolescence, particularly among males; reverse associations of ADHD symptoms with later PSMU were small in magnitude and sporadic. Screening for hard-to-control social media use, time spent on social media, and attention to sex-specific patterns may be warranted, although the population-based associations may be small.