The Preschool Attention-Deficit/Hyperactivity Disorder Treatment Study (PATS) 6-year follow-up

Area of Science:

• Child and Adolescent Psychiatry
• Developmental Psychology
• Neurodevelopmental Disorders

Background:

• Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder with significant impact on children's development.
• Early childhood diagnosis and treatment are crucial, but the long-term course of ADHD in preschoolers remains an area of active research.

Purpose of the Study:

• To investigate the longitudinal clinical course of ADHD symptom severity and diagnostic status in preschoolers over a six-year follow-up period.
• To examine factors influencing ADHD persistence and comorbidity in a cohort initially diagnosed in early childhood.

Main Methods:

• A cohort of 207 preschoolers diagnosed with ADHD was followed for six years.
• Parent and teacher ratings assessed symptom severity, while clinicians determined psychiatric diagnoses at multiple time points.
• Longitudinal changes in symptom severity and ADHD diagnosis were analyzed, considering comorbidity and medication status.

Main Results:

• ADHD symptom severity decreased from baseline to year 3 but remained moderate-to-severe through year 6.
• At year 6, 89% of participants still met ADHD diagnostic criteria.
• Comorbidity with oppositional defiant disorder and/or conduct disorder increased the risk of persistent ADHD diagnosis.

Conclusions:

• Preschool ADHD is a relatively stable diagnosis with a generally chronic course over six years.
• Young children with moderate-to-severe ADHD experience persistent symptoms and impairment despite medication.
• There is a critical need for more effective ADHD intervention strategies tailored for the preschool population.