Brain Iron Could Be a Valuable Biomarker for ADHD
Low levels of iron in the brain could be a signal for attention deficit/hyperactivity disorder (ADHD), according to new research reported at the Radiological Society of North America meeting.
Kristina Fiore reports a small study of children and adolescents with ADHD, led by Vitria Adisetiyo, Ph.D, found that those who have never received medication for their condition had significantly lower levels of brain iron picked up by magnetic correlation field (MFC) imaging compared to control participants and those being treated with drugs for the condition.
Current ADHD diagnose relies entirely on subjective information from the patient. A measurable biomarker to confirm the diagnosis could increase confidence in the diagnosis, but it could also be an important tool for preventing the overmedication of children with addictive psychostimulant medications.
“It would be beneficial when the psychiatrist is less confident of a diagnosis, if you could put a patient in a scanner for 15 minutes and confirm that brain iron is low,” she said in a statement.
There has been previous research hoping to find a biomarker for ADHD, including genetic susceptibility, but there has not been a reliable marker discovered. However, few previous studies have looked at levels of iron in the brain.
Adisetiyo explained that there is a fundamental relationship between the amount of brain iron and dopamine, a neurotransmitter that is a key target of stimulant drugs for the condition. Iron is needed for the creation and regulation of dopamine, and dopamine has been shown to be sensitive to changes in brain iron.
This leads the researchers to believe brain iron may be a reflection of dopamine levels and thus a reliable insight into the diagnosis of ADHD.
The researchers did note that the issue appears to be with how the brain absorbs iron, not the levels of iron in the body as a whole. Most of the kids in the study had normal levels in serum tests, so simply taking an iron supplement isn’t going to help.
“It may be a problem with absorption in the brain [specifically],” she said. “It suggests iron supplementation is not the route to go.”