Background: In Tourette syndrome (TS) as a neurodevelopmental disorder not only the tics but also the comorbid conditions change with increasing age. ADHD is highly comorbid with TS and usually impairs psychosocial functioning more than the tics. Its impact on further comorbidity during development is important for clinical practice and still a matter of debate.
Method: Aspects of developmental psychopathology considering the impact of ADHD were examined by logistic regression (year wisely) in a cross-sectional sample of children and adolescents (n = 5060) from the TIC database.
Results: In TS+ADHD (compared to TS-ADHD) higher rates of comorbid conditions like OCD, anxiety disorders, CD/ODD and mood disorders were found in children (5-10 years). In adolescents (11-17 years) higher comorbidity rates in TS+ADHD remained only for CD/ODD and mood disorders. Accordingly, for OCD and anxiety disorders there was a steeper year wise increase of these comorbidities in TS-ADHD while it was a similar for CD/ODD and mood disorders in TS-ADHD as well as TS+ADHD.
Conclusion: Children with TS+ADHD have more comorbidities than the TS-ADHD group, whereas in both adolescent groups this did no longer hold for OCD and anxiety disorders. These findings indicate that in TS comorbid ADHD is associated with high rates of externalizing and internalizing problems, whereas TS without ADHD is associated only with internalizing problems in adolescence.