Neurocognitive function in attention-deficit-hyperactivity disorder with and without comorbid disruptive behaviour...

Area of Science:

• Neuroscience
• Child Psychology
• Psychiatry

Background:

• Attention-deficit-hyperactivity disorder (ADHD) is a common neurodevelopmental disorder.
• Comorbid oppositional defiant disorder (ODD) and conduct disorder (CD) frequently co-occur with ADHD.
• Understanding the impact of these comorbidities on ADHD symptomology and neurocognitive function is crucial for effective treatment.

Purpose of the Study:

• To investigate the influence of comorbid ODD and CD on ADHD symptom levels.
• To examine how these comorbidities affect the relationship between neurocognitive deficits and ADHD symptom severity.

Main Methods:

• A cross-sectional study involving 200 children (6-12 years) diagnosed with ADHD, combined type.
• Participants were categorized into ADHD alone, ADHD with ODD, and ADHD with CD groups; medication-naive status was confirmed.
• Neurocognitive functions (spatial span, working memory, etc.) and ADHD/externalizing symptoms were assessed using parent and teacher reports, compared against healthy controls.

Main Results:

• Children with ADHD and comorbid ODD or CD exhibited higher parent-reported externalizing symptoms than those with ADHD alone.
• No significant differences in neurocognitive function were found between ADHD groups with or without ODD/CD.
• All ADHD groups performed worse than healthy controls, with specific neurocognitive deficits correlating with ADHD symptom severity in ADHD alone and ADHD+CD groups.

Conclusions:

• ADHD symptom severity correlates with executive function impairments in ADHD alone, but this link can be masked by comorbid ODD or CD.
• Children with ADHD and CD may share similar underlying dysfunctions with ADHD alone.
• ADHD with ODD might represent a maladaptive response to underlying ADHD-related neurocognitive and behavioral issues.