Asherson and Agnew-Blais review evidence from prospective, longitudinal studies in Brazil, New Zealand, Sweden, the United Kingdom and the United States showing that ADHD can emerge for the first time in adolescence or young adulthood. These findings defy conventional wisdom specifying that ADHD is, by definition, a disorder that emerges in childhood. We discuss possible explanations for the late-onset of ADHD, including the removal in adolescence or young adulthood of features of a young person's environment that played a buffering role against the emergence of symptoms and heterotypic continuity in a general liability to psychopathology that is present from childhood.
© 2019 Association for Child and Adolescent Mental Health.