[Electroencephalographic alterations in children with attention deficit hyperactivity disorder].

AIMS: The aim of this work was to analyse and determine the electroencephalographic alterations presented in patients with attention deficit hyperactivity disorder (ADHD) between 4 and 14 years of age.

PATIENTS AND METHODS: The research consisted in a prospective observation-based analytical study, conducted between January and July 2010, to detect electroencephalographic abnormalities in the population of children diagnosed with ADHD who visited the Doctor Rodolfo Nieto Padron Children's Hospital. The Latin-American ADHD questionnaire and the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, were administered, together with a survey for detecting risk factors. An electroencephalogram (EEG) was later performed and a database was set up to record information about age, sex, perinatal asphyxia, family history of seizures, medicine used to control ADHD, the presence of tics and itemised findings from the EEG. A note was made of whether the EEG trace was normal or abnormal and, in the case of the latter, the location of the EEG phenomenon was stated.

RESULTS: A total of 50 patients with EEG findings were included, with an average of 7.3 years; there was a predominance of male patients, with 36 males (72%) versus 14 females (28%). We found 21 children with motor tics (42%) and four with a history of having had seizures (8%), two of whom had previously been diagnosed with epilepsy. The total number of EEG within normal limits was 31 (34.5%) and there were 19 that could be considered abnormal (15.5%). Although the presence of abnormal EEG patterns existed in a significant group, it was not related to the presence of tics in the patients. Moreover, a direct relationship was found between the presence of seizures and EEG abnormalities.

CONCLUSIONS: No correlation was observed between poor educational achievement and an abnormal EEG. EEG is the best study for determining whether there are epileptogenic foci, although there is no clinical correlation. The most frequent location of the abnormalities observed in the EEG of a patient with ADHD is in the temporal lobe.