ABSTRACT
INTRODUCTION: Attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD) are frequently co-occurring disorders in children and adolescents. However, their clinical status among adults is still under discussion. This study analyzes how the current clinical presentation of adult ADHD might be influenced by a lifetime history of CD and ODD. METHODS: We compared three groups of patients: ADHD without history of CD/ODD (n = 178), ADHD + history of ODD (n = 184), and ADHD + history of CD (n = 96). RESULTS: A history of CD (and to a lower extent ODD) is associated with a more severe and externalizing profile. CONCLUSION: Past CD and ODD entail a significant negative mental health impact on persistent ADHD, reinforcing the importance of actively assessing the developmental history of adult ADHD patients.