ABSTRACT
This study examined the contributions of childhood symptom dimensions and aspects of methylphenidate (MPH) treatment to the prediction of young adult outcomes in boys who were referred to a child psychiatry outpatient clinic. They were diagnosed with hyperkinetic reaction of childhood/minimal brain dysfunction, and given MPH for an average of 30 months. Including significant effects and statistical trends, childhood Inattention-Over-activity was uniquely associated with fewer than 10% of adult outcomes such as schizotypic features, impairment on the Global Assessment Scale (GAS), and unemployment. Childhood aggression was uniquely associated with 38% of adult outcomes such as lifetime diagnoses of major depression, drug abuse disorder, and antisocial personality disorder; MMPI PD, PA, and SC scores; and six additional measures of adult impairment and life circumstances-extending external validation of the two-factor model to young adulthood. For 20 young adult outcomes (63%), aspects of childhood treatment with MPH had no lasting effects. For one adult outcome (3%), a lasting negative effect of childhood drug treatment was found; better initial response to medication was associated with not graduating from high school. For 11 young adult outcomes (34%), however, aspects of childhood MPH treatment had positive effects that lasted long after treatment was discontinued. Higher dosage was associated with fewer diagnoses of alcoholism or suicide attempts. Better response to medication was associated with lower MMPI D scores and better social functioning. Longer medication duration was associated with fewer schizotypic features, lower MMPI MA scores, higher WAIS Performance and Full Scale IQs, and better WRAT Reading and Arithmetic performance.
