Karen J Mathewson, Christina A Brook, Ryan J Van Lieshout, Louis A Schmidt
For a significant proportion of children with attention-deficit/hyperactivity disorder (ADHD), symptoms persist in adulthood, with enduring consequences for psychosocial functioning. While hereditary factors for this multifactorial disorder have garnered considerable attention, environmental risks for ADHD remain relatively under-researched. The main goal of this study was to identify characteristics of the child or the family environment that may influence longitudinal trajectories of ADHD. Using growth mixture modeling (GMM), we identified three distinct latent class trajectories of ADHD symptoms assessed at 8, 14, and 23 years of age in a prospectively-followed cohort of 306 participants (46% male; 94% White): a stable high trajectory (14.3%), a descending trajectory (24.7%), and a stable low trajectory (61.0%). As expected, the high class had more psychosocial impairments and lower socioeconomic attainment than the other classes at age 32 years. Male sex, low birth weight, child oppositional behavior, and childhood exposure to negative maternal mood were associated with ADHD symptoms in the high and descending classes. Retrospectively reported child maltreatment was more closely associated with membership in the high class than the low class. Sexual abuse was more closely associated with membership in the high class than the descending class. Further study is warranted to ascertain whether child maltreatment is instrumental in maintaining ADHD symptoms in children who are vulnerable to ADHD, and to determine the timing of its detrimental effects.225 words.