Reduced right frontal cortical thickness in children, adolescents and adults with ADHD and its correlation to clinical variables: a cross-sectional study.
OBJECTIVE
Some longitudinal magnetic resonance imaging (MRI) studies have shown reduced volume or cortical thickness (CT) in the frontal cortices of individuals with attention-deficit/hyperactivity disorder (ADHD). These studies indicated that the aforementioned anatomical abnormalities disappear during adolescence. In contrast, cross-sectional studies on adults with ADHD have shown anatomical abnormalities in the frontal lobe region. It is not known whether the anatomical abnormalities in ADHD are a delay or a deviation in the encephalic maturation. The aim of this study was to compare CT in the frontal lobe of children, adolescents and adults of both genders presenting ADHD with that in corresponding healthy controls and to explore its relationship with the severity of the illness.


METHODS
An MRI scan study was performed on never-medicated ADHD patients. Twenty-one children (6-10 year-olds), twenty adolescents (14-17 year-olds) and twenty adults (25-35 year-olds) were matched with healthy controls according to age and sex. CT measurements were performed using the Freesurfer image analysis suite.


RESULTS
The data showed regions in the right superior frontal gyrus where CT was reduced in children, adolescents and adults with ADHD in contrast to their respective healthy controls. The CT of these regions correlated with the severity of the illness.


CONCLUSIONS
In subjects with ADHD, there is a thinning of the cortical surface in the right frontal lobe, which is present in the children, adolescents and in adults.
Centro Estatal de Salud Mental, Servicios de Salud del Estado de Querétaro, Avenida 5 de Febrero 105, Los Virreyes CP 76170 Querétaro, México. almeidal@prodigy.net.mx
Luis G
LG
Almeida
Josefina
J
Ricardo-Garcell
Hugo
H
Prado
Lázaro
L
Barajas
Antonio
A
Fernández-Bouzas
David
D
Avila
Reyna B
RB
Martínez
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology / Q000473:pathology*; D002648:Child; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D005625:Frontal Lobe / Q000254:growth & development / Q000473:pathology*; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult