Imaging the influence and interaction of genes and stimulant medication on attention in Attention Deficit Hyperactivity Disorder (ADHD).

In adolescents with Attention Deficit Hyperactivity Disorder (ADHD), how does methylphenidate compared to placebo, effect Blood Oxygenation Level Dependent (BOLD) response as measured by functional Magnetic Resonance Imaging (fMRI), and how does the response vary with difference in the dopamine transporter (DAT1) gene.

Status

Completed

Phases

Phase 3

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12610000652077

Enrollment

Registered

2010-08-11

Start date

2010-09-06

Completion date

2012-07-13

Last updated

2024-09-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

Attention deficit hyperactivity disorder (ADHD) is a common behavioural disorder of childhood with negative adult outcomes. The disorder is characterised by problems of attention, impulsivity (e.g., acting without thinking) and hyperactivity (e.g., being constantly on the go). The disorder appears to be strongly genetic with the most likely situation being one in which many genes each contribute a small amount of risk for the disorder. ADHD is also associated with a range of cognitive problems (i.e., problems of concentrating, planning etc). This project takes an imaging genetics approach, using functional MRI to understand the functional effects for brain and cognition of a genetic risk factor for ADHD- the dopamine transporter gene (DAT1) - which we have previously shown to influence attention. It is also well-established that not all children with ADHD achieve equal benefit from stimulant medications, such as methylphenidate (MPH), either in terms of behavioural, cognitive or academic outcomes. We will therefore examine the interaction of DAT1 genotype and MPH treatment on the neural correlates of spatial attention using fMRI. This project will help to elucidate the neurobiological mechanisms of ADHD.

Interventions

This is a crossover trial. Participants will take a single dose of methylphenidate (20mg capsule) in one session, and a placebo capsule on the other session. Sessions are counterbalanced and conducted exactly 2 weeks apart.

Study design

Allocation

Randomised controlled trial

Intervention model

Crossover

Primary purpose

Treatment

Masking

Blinded (masking used)

Eligibility

Sex/Gender

All

Age

8 Years to 18 Years

Healthy volunteers

Inclusion criteria

ADHD (combined type) Healthy, matched control adolescents (Placebo only) right handed

Exclusion criteria

Weight under 35kg Full scale Intelligence Quotient (FSIQ) >70 Conners Parent Rating Scale (CPRS) >65 for ADHD, <60 for controls gluten intolerance (due to presence in placebo) wearing dental braces no reading disabilities, no comorbidities, of major depression, Autism Spectrum Disorders, or psychosis

Outcome results