Differences between attention-deficit disorder with and without hyperactivity:: a 1H-magnetic resonance spectroscopy study

Using proton magnetic resonance spectroscopy (H-1-MRS) to investigate possible neurometabolic differences between the predominantly inattentive subtype (ADHD-1), the combined subtype (ADHD-C) and normal controls. Proton spectra were acquired bilaterally on the lenticular nucleus in 20 schoolboys having ADHD and 10 matched controls. The boys with ADHD were divided into ADHD-C subtype (n = 10) and ADHD-1 subtype (n = 10) according to DSM-IV criteria. The peaks of N-acetylaspartate (NAA), Choline moieties (Cho), myoinositol (mI), creatine (Cr) and alpha-Glx were measured and their ratios to Cr were calculated. One-way ANOVA and post-hoc Bonferroni tests were used to detect the difference of the peak-area ratios of NAA, Cho, ml, and a-Glx to Cr among the three groups. There was a significant overall group difference in the NAA/Cr ratio both in the right and left lenticular nucleus (right: P = 0.002; left: P = 0.003). Only the ADHD-C subtype group showed a significant difference with controls (right: P = 0.001; left: P = 0.003) the right lenticular nucleus, the NAA/Cr ratio in the ADHD-C group was significantly lower than that in the ADHD-1 group (P = 0.012). In the left lenticular nucleus, the NAA/Cr ratio in the ADHD-C group showed a significant trend compared to the ADHD-1 group (P = 0.06). This study demonstrated the existence of measurable difference between children with ADHD-C and ADHD-1 using H-1-MRS. (c) 2004 Elsevier B.V. All rights reserved.