Volumetric MRI differences in treatment-naive vs chronically treated children with ADHD

University of Nottingham, Nottigham, England, United Kingdom
Neurology (Impact Factor: 8.29). 10/2006; 67(6):1023-7. DOI: 10.1212/01.wnl.0000237385.84037.3c
Source: PubMed


To determine if there are differences in the volume of the caudate and anterior cingulate cortex (ACC) between children with attention deficit hyperactivity disorder (ADHD) and controls, and if such differences are related to the subjects' history of stimulant treatment.
We performed a case-control study in an academic medical center. Twenty-one healthy controls, 16 children with ADHD, combined type with a history of stimulant treatment, and 14 children with ADHD, combined type treatment naïve, underwent structural MRI. All children with ADHD were medication-free at the time of the MRI. Regional hemispheric volumes (in cm3) of caudate and anterior cingulate cortex were determined.
There were significant differences bilaterally on caudate volume for both ADHD groups vs controls, with no difference between the ADHD groups on either side. In contrast, the right ACC was significantly smaller for the ADHD-treatment naïve (ADHD/TN) group compared to the ADHD-treated (ADHD/Rx) and control group. The volume of left ACC approached significance contrast between ADHD/RX and ADHD/TN. There were no differences found between the ADHD/Rx and controls on the ACC volumes bilaterally.
The results from this study indicate a relationship of previous treatment history with caudate and anterior cingulate volumetric changes in children with attention deficit hyperactivity disorder-combined type.

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Available from: Margaret Semrud-Clikeman, Apr 10, 2015
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    • "The main strengths of the study are the relatively large sample size of ADHD and control groups and the fact that all patients were medication-näive at time of scanning. This is important given the long term effects of stimulant medication on brain function and structure (Nakao et al., 2011; Pliszka et al., 2006). However, also some limitations of the present study should be noted. "
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    • "The strength of the study is the use of probabilistic GPC methods that confers multiple benefits for clinical studies. Another strength is the inclusion of mostly (73%) medication-naïve ADHD patients, since long-term stimulant medication has been associated with more normal GM and cortical thickness of fronto-cingulate, parietal, cerebellar and striatal regions[2], [52], [62]–[65] and 100% medication-naïve ASD patients. To increase the homogeneity of the sample, we included only males with the combined hyperactive-impulsive and inattentive subtype of ADHD. "
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