Brain metabolism in teenagers with attention-deficit hyperactivity disorder

Abstract

Objectives: We sought to obtain and compare values of cerebral glucose metabolism in normal minors and minors with Attention Deficit Hyperactivity Disorder (ADHD). We also sought to confirm our earlier findings of reduced brain metabolism in adults with ADHD, and to examine whether these results might be diagnostically useful.

Design: Case-control study.

Setting: Adolescents were recruited to National Institutes of Health Clinical Center/Research Facility through advertisement at local high schools and ADHD organizations.

Patients: Subjects were 10 normal adolescents and 10 adolescents with ADHD diagnosed with structured interviews using DSM-III-R criteria.

Main outcome measures: Positron emission tomography and fludeoxyglucose F18 were used to study cerebral glucose metabolism in minors while they performed an auditory-attention task.

Results: Global or absolute measures of metabolism did not statistically differ between groups, although hyperactive girls had a 17.6% lower absolute brain metabolism than normal girls. As compared with the values for the controls, normalized glucose metabolism was significantly reduced in six of 60 specific regions of the brain, including an area of the left anterior frontal lobe (P < .05). Lower metabolism in that specific region of the left anterior frontal lobe was significantly inversely correlated with measures of symptom severity (P < .001-.009, r = -.56 to -.67).

Conclusions: Global or absolute measures of metabolism using positron emission tomography and fludeoxyglucose F18 did not statistically differentiate between normal adolescents with ADHD. Positron emission tomography scans can be performed and are well tolerated by normal teenagers and teenagers with ADHD. The feasibility of normal minors participating in research involving radiation was established.