Attention-Deficit Disorders and Epilepsy in Childhood: Incidence, Causative Relations and Treatment Possibilities

Abstract

At least 20% of children with epilepsy have clinical attention-deficit hyperactivity disorder (ADHD) compared to 3% to 7% of the general pediatric population. Several mechanisms may account for the high prevalence, such as a common genetic propensity, noradrenergic system dysregulation, subclinical epileptiform discharges, or even seizures, antiepileptic drug effects, and psychosocial factors. At the same time, children with attention-deficit hyperactivity disorder have a higher than normal rate of electroencephalography abnormalities (5.6-30.1% vs. 3.5%). Methylphenidate treatment is equally efficient in children with isolated attention-deficit hyperactivity disorder and in children with attention-deficit hyperactivity disorder and epilepsy (70%-77%). Electroencephalography screening in patients with attention-deficit hyperactivity disorder in the absence of other clinical indications or before starting methylphenidate treatment is not currently indicated. Methylphenidate is considered safe for use in children who are seizure-free. However, the few reports of seizure aggravation in methylphenidate-treated children with uncontrolled epilepsy have raised concern.

TDAH nas epilepsias: prevalência e fatores de risco

“…Nesse contexto, algumas hipóteses não excludentes têm sido propostas. A primeira argumenta que a co-ocorrência se deve a fatores circunstanciais independentes pelo fato de a epilepsia e o TDAH serem comuns na infância (Kaufmann, Goldberg-Stern, & Shuper, 2009).…”

Electroencephalographic Abnormalities in Non-epileptic Children with Attention-Deficit /Hyperactivity Disorder

“…The prevalence of epileptiform discharges in patients with ADHD has been reported to range from 6.1% [15] to 53%, [20] which is much higher than that for healthy children (3.5%) [21]. The wide variation in the frequency of EEG abnormalities may be due to different research methods, duration of EEG, EEG activation, and the enrolled study subjects.…”

Possíveis interfaces entre TDAH e epilepsia

“…Nos pacientes com crises controladas, a medicação psicoestimulante poderia ser utilizada 65,70 . Naqueles com crises em atividade, são necessárias cuidadosa observação clínica e monitorização eletroencefalográfica durante o tratamento 59,65,70,[72][73][74][75][76] . Em portadores de TDAH que apresentam descargas epilépticas focais ao EEG e que nunca apresentaram crises, o uso de psicoestimulantes sem associação a drogas anticonvulsivantes parece seguro 8,59,76 .…”

“…Estudos bem elaborados que investiguem o efeito de fármacos antiepilépticos para o tratamento do TDAH em pacientes com descargas eletroencefalográficas frequentes ainda são escassos. Apesar de terem sido encontrados alguns trabalhos na literatura que descrevem melhora cognitiva após tratamento com fármacos antiepilépticos com o objetivo de suprimir essas descargas, especialmente quando o déficit cognitivo é acompanhado de padrões eletroencefalográficos do tipo ponta-onda contínua durante o sono, deve-se ter cautela na prescrição de antiepilépticos com esse objetivo, pois, reconhecidamente, alguns fármacos antiepilépticos podem afetar as funções cognitivas e gerar piora dos sintomas [66][67][68]76 .…”