Not EEG abnormalities but epilepsy is associated with autistic regression and mental functioning in childhood autism

Abstract

The aim of the study was to investigate the potential association of epilepsy and EEG abnormalities with autistic regression and mental retardation. We examined a group of 77 autistic children (61 boys, 16 girls) with an average age of 9.1 +/- 5.3 years. Clinical interview, neurological examination focused on the evaluation of epilepsy, IQ testing, and 21-channel EEG (including night sleep EEG recording) were performed. Normal EEGs were observed in 44.4% of the patients, non-epileptiform abnormal EEGs in 17.5%, and abnormal EEGs with epileptiform discharges in 38.1% of the patients. Epilepsy was found in 22.1% of the subjects. A history of regression was reported in 25.8% of the patients, 54.8% of the sample had abnormal development during the first year of life, and 79.7% of the patients were mentally retarded. Autistic regression was significantly more frequent in patients with epilepsy than in non-epileptic patients (p = 0.003). Abnormal development during the first year of life was significantly associated with epileptiform EEG abnormalities (p = 0.014). Epilepsy correlated significantly with mental retardation (p = 0.001). Although the biological basis and possible causal relationships of these associations remain to be explained, they may point to different subgroups of patients with autistic spectrum disorders.

Management of Children With Autism Spectrum Disorders

“…98 Epileptiform abnormalities on electroencephalography (EEG) are common in children with ASDs, with reported frequencies ranging from 10% to 72%. 99 Some studies have suggested that epileptiform abnormalities on EEG 100 and/or epilepsy 101 are more common in the subgroup of children with ASDs who have a history of regression, whereas other studies have not demonstrated this association. 102,103 Autistic regression with epileptiform abnormalities on EEG has been compared by analogy with Landau-Kleffner syndrome and electrical status epilepticus in sleep, but there are important differences between these conditions, and the treatment implications are unclear.…”

Epilepsy and Autism

“…In addition to an increased prevalence of epilepsy in individuals with ASD, there is also a marked increased incidence of epileptiform activity on the EEGs of people with ASD (Giovanardi et al 2000;Hrdlicka et al 2004;Canitano et al 2005;Gabis et al 2005;Hughes and Melyn 2005;Baird et al 2006;Chez et al 2006;Kim et al 2006;Akshoomoff et al 2007;Hara 2007;Parmeggiani et al 2007;Giannotti et al 2008;Spence and Schneider 2009). Whereas interictal spikes occur in .5% of normally developing children without a history of epilepsy (EegOlofsson et al 1971), more recent studies have shown that up to 60% of EEG records from children with ASD have interictal spikes (Hughes and Melyn 2005) and many of the children with abnormal EEGs do not have a history of epilepsy (Hughes et al 2015).…”

Landau kleffner syndrome, electrical status epilepticus in sleep and autistic regression: an overview of literature / Landau kleffner sendromu, uykuda elektriksel status epileptikus ve otistik regresyon: Literatüre bir bakış

“…Some studies, especially the older reports, demonstrated higher rates of epilepsy in autistic children with a history of regression versus the autistic children without regression (79,80,103,104). These results raised the questions if there is a clinically important relation between epileptiform EEG and/or epilepsy and AR as it is shown in ESES or LKS patients.…”