Parental education predicts change in intelligence quotient after childhood epilepsy surgery.

OBJECTIVE: To know whether change in the intelligence quotient (IQ) of children who undergo epilepsy surgery is associated with the educational level of their parents. METHODS: Retrospective analysis of data obtained from a cohort of children who underwent epilepsy surgery between January 1996 and September 2010. We performed simple and multiple regression analyses to identify predictors associated with IQ change after surgery. In addition to parental education, six variables previously demonstrated to be associated with IQ change after surgery were included as predictors: age at surgery, duration of epilepsy, etiology, presurgical IQ, reduction of antiepileptic drugs, and seizure freedom. We used delta IQ (IQ 2 years after surgery minus IQ shortly before surgery) as the primary outcome variable, but also performed analyses with pre- and postsurgical IQ as outcome variables to support our findings. To validate the results we performed simple regression analysis with parental education as the predictor in specific subgroups. RESULTS: The sample for regression analysis included 118 children (60 male; median age at surgery 9.73 years). Parental education was significantly associated with delta IQ in simple regression analysis (p = 0.004), and also contributed significantly to postsurgical IQ in multiple regression analysis (p = 0.008). Additional analyses demonstrated that parental education made a unique contribution to prediction of delta IQ, that is, it could not be replaced by the illness-related variables. Subgroup analyses confirmed the association of parental education with IQ change after surgery for most groups. SIGNIFICANCE: Children whose parents had higher education demonstrate on average a greater increase in IQ after surgery and a higher postsurgical--but not presurgical--IQ than children whose parents completed at most lower secondary education. Parental education--and perhaps other environmental variables--should be considered in the prognosis of cognitive function after childhood epilepsy surgery.

Visual memory after epilepsy surgery in children: a standardized regression-based analysis of group and individual outcomes.

Visual memory is vulnerable to epilepsy surgery in adults, but studies in children suggest no change or small improvements. We investigated visual memory after epilepsy surgery, both group-wise and in individual children, using two techniques to assess change: 1) repeated measures analysis of variance (ANOVA) and 2) an empirically based technique for detecting cognitive change [standardized regression-based (SRB) analysis]. A prospective cohort consisting of 21 children completed comprehensive assessments of memory both before surgery (T0) and 6 (T1), 12 (T2), and 24 months (T3) after surgery. For each patient, two age- and gender-matched controls were assessed with the same tests at the same intervals. Repeated measures ANOVA replicated the results of previous studies reporting no change or minor improvements after surgery. However, group analysis of SRB results eliminated virtually all improvements, indicating that the ANOVA results were confounded by practice effects. Standardized regression-based group results showed that in fact patients scored lower after surgery than would be predicted based on their presurgical performance. Analysis of individual SRB results showed that per visual memory measure, an average of 18% of patients obtained a significantly negative SRB score, whereas, on average, only 2% obtained a significantly positive SRB score. At T3, the number of significantly negative SRB scores outweighed the number of significantly positive SRB scores in 62% of patients. There were no clear associations of clinical variables (including side and site of surgery and postsurgical seizure freedom) with memory outcome. The present analysis revealed that given their individual presurgical functioning, many children obtained disappointing results on some visual memory tests after epilepsy surgery. Comparison of the SRB analysis with ANOVA results emphasizes the importance of empirically based techniques for detecting cognitive effects of epilepsy surgery in childhood.

Epilepsy surgery in children: no further threat to theory of mind.

To investigate whether theory of mind (ToM), an important requirement for adaptive social functioning, is different between children with pharmacologically refractory epilepsy who undergo epilepsy surgery and healthy control children, whether ToM is affected by epilepsy surgery in these children, and whether ToM is associated with demographic or epilepsy variables. The "ToM storybooks", a psychometrically sound ToM instrument designed for children, was administered shortly before and 0.5, one and two years after surgery as part of a neuropsychological assessment. Fifteen patients (mean age: 7.1 years) completed the ToM storybooks before and at least twice after surgery. Two sex- and age-matched healthy control children were included per patient. Linear mixed models were used to analyse differences between patients and controls. The association between ToM and demographic, epilepsy and surgical variables was explored. Patients had lower ToM scores than healthy control children, even when corrected for verbal intelligence quotient (VIQ). Epilepsy surgery had neither a harmful nor a favourable effect on ToM. Later epilepsy onset and temporal origin of epilepsy were associated with higher (better) ToM scores relative to earlier epilepsy onset and extra-temporal epilepsy (including hemispherotomy in one case). Children in whom the amygdala was resected had worse ToM scores. Children with refractory epilepsy have a ToM deficit that may not be accounted for by lower VIQ. Epilepsy surgery does not affect ToM functioning. Younger age at epilepsy onset is associated with poorer ToM, and temporal epilepsy with better ToM. Finally, the amygdala is implicated in ToM deficit. Patients and their parents should be educated about the possible consequences of epilepsy with regards to the development of social cognition and should be guided in order to help improve ToM.

Lexicon before and after epilepsy surgery in adolescents.

OBJECTIVE: Poor performance on confrontation naming tasks by children and adolescents with pharmacologically intractable epilepsy has been interpreted as indicating impairments of lexicon, that is, the store of words in long-term memory. However, confrontation naming performance crucially depends not only on word knowledge but also on other functions such as fluency. We applied an alternative method to assess lexicon with the aim of tracing deficits in lexicon before and after surgery in adolescents with pharmacologically intractable epilepsy. METHOD: Sixteen patients and 32 age- and sex-matched controls completed the Dutch version of the controlled oral word production task. Responses were used to calculate indices of lexical fluency (retrieval efficiency), lexical breadth (vocabulary size), and lexical depth (knowledge of word properties), as well as use of search strategies. RESULTS: Adolescents with pharmacologically intractable epilepsy had lower lexical fluency scores than healthy peers, but did not differ from them on the dimensions of lexical breadth and lexical depth. Patients demonstrated reduced use of search strategies. In fact, the difference in lexical fluency between patients and controls disappeared after controlling for Full Scale IQ (obtained using the Dutch version of the 3rd edition of the Wechsler Intelligence Scale for Children (WISC-IIINL; Kort et al., 2005; Wechsler, 2002) or-for older children-the Dutch version of the first edition of the Kaufman Adult and Adolescent Intelligence Test (KAIT; Kaufman & Kaufman, 1993; Mulder, Dekker, & Dekker, 2004) and use of search strategies. In patients, changes in the use of the antiepileptic drug carbamazepine were associated with lexical fluency. CONCLUSION: Adolescents with pharmacologically intractable epilepsy differ from their healthy peers mainly in lexical fluency, rather than word knowledge per se. (PsycINFO Database Record