Comorbidity among individuals classified with attention disorders

This study examined the frequency of comorbidity among ADHD and ADHD subtypes. Specific aspects of comorbidity were examined in the areas of learning disorders, disruptive behavior disorders, and affective disorders. Two analyses were performed. The first analysis compared the comorbid second and third diagnoses for 287 individuals with a primary diagnosis of ADHD (Predominately Inattentive Type or Predominately Hyperactive-Impulsive Type) with a comparison sample (n = 290) who did not have a primary diagnosis of ADHD. The second analysis examined the comorbidity with specific ADHD subtypes. This analysis compared the comorbid second and third diagnosis of individuals with a primary ADHD subtype diagnosis of Predominately Inattentive (n = 143) with individuals who have a primary ADHD subtype diagnosis of Predominately Hyperactive-Impulsive (n = 143). Results from the first analysis indicated significant overlap between the diagnosis of ADHD and the diagnosis of learning disorders and disruptive behavior disorders but not for affective disorders. Results from the second analysis indicated that only conduct disorders were comorbid with certain ADHD subtypes, with disruptive behavior disorders being more likely to be diagnosed with ADHD Hyperactive-Impulsive Type than with ADHD Inattentive Type.