MedicalResearch.com: What are the main findings of the study?
Dr. Adisetiyo: Using a non-invasive MRI method called magnetic field correlation imaging, we detected significantly reduced striatal and thalamic brain iron in medication-naive children and adolescents with ADHD compared to age-, gender- and IQ-matched typically developing controls. ADHD patients who had a history of psychostimulant medication treatment (e.g. Ritalin, Aderrall) had brain iron levels comparable to controls, suggesting brain iron may normalize with psychostimulants. Blood iron measures did not differ between patients and controls.
MedicalResearch.com: Were any of the findings unexpected?
Dr. Adisetiyo: Although it is known that brain iron is required for dopamine metabolism, little is known about the mechanistic details. Thus, it was unexpected that our findings paralleled a recent meta-analysis of ADHD molecular imaging studies that identified reduced dopamine biomarkers in medication-naive ADHD patients and increased dopamine biomarkers in patients with a history of psychostimulant treatment. This suggests that brain iron levels may indirectly reflect the disrupted dopamine pathway in ADHD that is targeted by psychostimulant medication.
MedicalResearch.com: What should clinicians and patients take away from your report?
Dr. Adisetiyo: Although the findings remain preliminary and require replication in a larger longitudinal study, clinicians and patients should know that with the advent of improved technology, we are making progress in identifying promising non-invasive biomarkers of ADHD that may help inform traditional clinical diagnosis. These early findings suggest that low brain iron (and not blood iron) may represent a potential non-invasive ADHD diagnostic biomarker that responds to psychostimulant use.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Dr. Adisetiyo: Our report highlights the importance of accounting for medication history in studies that examine potential ADHD biomarkers as these biomarkers may adapt and change as a result of medication.