Metabolite changes resulting from treatment in children with ADHD: a 1H-MRS study.

Previously the authors noted an increase in glutamatergic tone in children with attention deficit hyperactivity disorder compared with age- and gender-matched control subjects. In this study they examine the effect of treatment on metabolite concentrations. Fourteen children with attention deficit hyperactivity disorder were investigated medication free and after treatment, using proton magnetic resonance spectroscopy. In the prefrontal cortex and striatum, metabolite peaks of N-acetyl-aspartate, glutamate/glutamine/gamma-aminobutyric acid, creatine/phosphocreatine, and choline compounds were measured, and ratios of the peaks were calculated and compared before and after treatment. The glutamate/glutamine/gamma-aminobutyric acid-to-creatine/phosphocreatine ratio decreased significantly in the striatum. No other metabolites demonstrated any change in response to medication. These findings suggest that glutamate may be involved in treatment response in attention deficit hyperactivity disorder, especially in the striatum.