title: ADHD characteristics: I. Concurrent co-morbidity patterns in children & adolescents.
abstract: OBJECTIVE
  342 Caucasian subjects with attention deficit/hyperactivity disorder (ADHD) were recruited from pediatric and behavioral health clinics for a genetic study. Concurrent comorbidity was assessed to characterize the clinical profile of this cohort.
  
  
  METHODS
  Subjects 6 to 18 years were diagnosed with the Schedule for Affective Disorders & Schizophrenia for School aged Children (K-SADS-P IVR).
  
  
  RESULTS
  The most prevalent diagnoses co-occurring with ADHD were Oppositional Defiant Disorder (ODD) (40.6%), Minor Depression/Dysthymia (MDDD) (21.6%), and Generalized Anxiety Disorder (GAD) (15.2%). In Inattentive ADHD (n = 106), 20.8% had MDDD, 20.8% ODD, and 18.6% GAD; in Hyperactive ADHD (n = 31) 41.9% had ODD, 22.2% GAD, and 19.4% MDDD. In Combined ADHD, (n = 203), 50.7% had ODD, 22.7% MDDD and 12.4% GAD. MDDD and GAD were equally prevalent in the ADHD subtypes but, ODD was significantly more common among Combined and Hyperactive ADHD compared to Inattentive ADHD. The data suggested a subsample of Irritable prepubertal children exhibiting a diagnostic triad of ODD, Combined ADHD, and MDDD may account for the over diagnosing of Bipolar Disorder.
  
  
  CONCLUSIONS
  Almost 2/3rd of ADHD children have impairing comorbid diagnoses; Hyperactive ADHD represents less than 10% of an ADHD sample; ODD is primarily associated with Hyperactive and Combined ADHD; and, MDDD may be a significant morbidity for ADHD youths from clinical samples.
authors.affiliation: Department of Child and Adolescent Psychiatry, The Children's Hospital of Philadelphia, Philadelphia, PA, USA. elia@email.chop.edu
authors.forename: Josephine
authors.initials: J
authors.lastname: Elia
authors.forename: Paul
authors.initials: P
authors.lastname: Ambrosini
authors.forename: Wade
authors.initials: W
authors.lastname: Berrettini