Use of neuropsychological tests to identify high school students with epilepsy who later demonstrate inadequate performances in life

The Neuropsychological and Language Profile of Children with Benign Rolandic Epilepsy

PURPOSE

Benign rolandic epilepsy (BRE) has an excellent prognosis for seizures, but recent research has raised concerns using cognition as an outcome measure. Methodologic problems related to recruitment bias and assessment processes are evident in previous studies. With well-defined criteria for inclusion and comprehensive assessment, the aim of this study was to define the cognitive profile of children with BRE and to assess the effect of interictal EEG activity.

METHODS

Patients (n=42) were recruited from six EEG laboratories. The EEG features analyzed were spike frequency, trains, and laterality. Comprehensive neuropsychological and language assessments were conducted. Group means on cognitive measures were compared with normative means. Tests were correlated with EEG features.

RESULTS

The study demonstrated that children with BRE have normal intelligence and language ability. However, a specific pattern of difficulties in memory and phonologic awareness was found. Furthermore, a large proportion of children had disproportionate scores in these areas compared with intellectual and language ability. EEG features were minimally associated with cognitive difficulties, and no correlation was found with memory indices and tests of phonologic awareness.

CONCLUSIONS

Some children with BRE have specific difficulties in memory and phonologic processing skills, not explained by interictal activity. We recommend that pediatricians ask about academic performance specifically in areas of prereading, reading, spelling, and memory. If difficulties are suspected, assessment targeting phonologic awareness and memory are recommended, as they may not be reflected in overall intellectual and language ability. Difficulties in phonologic awareness affect literacy, and memory problems affect academic performance.

Development and validation of the Subjective Awareness of Neuropsychological Deficits Questionnaire for Children (SAND-C)

Although lowered awareness of abilities has been associated with poorer outcome in adults with neurological compromise, a dearth of research exists examining whether lowered awareness exists in younger populations. Using findings from recent literature and expert opinion, a 47-item Subjective Awareness of Neuropsychological Deficits Questionnaire for Children (SAND-C) was created to assess awareness of cognitive functioning in 6 domains (attention, psychomotor, visual-spatial, language, memory, and executive functioning). Confirmatory factor analysis (CFA) of the SAND-C was conducted on a sample consisting of 365 healthy children and 48 children with epilepsy. The SAND-C was found to have strong reliability. Factor analysis confirmed the a priori 6 factor model, but the 6-factor model was only marginally better than a more parsimonious 1-factor solution. Post-hoc exploratory factor analyses indicate that the SAND-C may measure more constructs for adolescents than for younger children. The difference between younger and older children may reflect developmental changes in metacognitive awareness and abstraction about their own abilities.

Neuropsychological predictors of academic underachievement in pediatric epilepsy: moderating roles of demographic, seizure, and psychosocial variables

PURPOSE

Academic underachievement is common in pediatric epilepsy. Attempts to identify seizure and psychosocial risk factors for underachievement have yielded inconsistent findings, raising the possibility that seizure and psychosocial variables play a complex role in combination with other variables such as neuropsychological functioning. This study cross-validated a neuropsychological measurement model for childhood epilepsy, examined the relation between neuropsychological functioning and academic achievement, and tested the degree to which demographic, seizure, and psychosocial variables moderate that relation.

METHODS

Children with chronic epilepsy (N = 173; ages 8 to 15 years; 49% girls; 91% white/non-Hispanic; 79% one seizure type; 79% taking one medication; 69% with active seizures) completed a comprehensive neuropsychological battery. Children diagnosed with mental retardation were excluded.

RESULTS

Structural equation modeling identified a three-factor measurement model of neuropsychological function: Verbal/Memory/Executive (VME), Rapid Naming/Working Memory (RN/WM), and Psychomotor (PM). VME and RN/WM were strongly related to reading, math, and writing; PM predicted writing only. Family environment moderated the impact of neuropsychological deficits on writing (p < or = 0.01) and possibly for reading (p = 0.05); neuropsychological deficits had a smaller impact on achievement for children in supportive/organized homes compared with children in unsupportive/disorganized homes.

CONCLUSIONS

These findings lend partial support for our theoretical model showing direct effects of neuropsychological function on achievement and the moderating role of family factors. This study suggests that a subgroup of children with epilepsy (those who have not only neuropsychological deficits but also disorganized/unsupportive home environments) are particularly at risk for adverse academic outcomes. Implications for intervention are discussed.

Motor speed is a contaminating factor in evaluating the "cognitive" effects of phenytoin

Many studies suggestive of adverse effects of phenytoin (PHT) on mental abilities have used testing procedures which have timed or motor speed elements. Therefore, to what degree the motor speed element alone may have resulted in attributing adverse higher level intellectual or cognitive effects to PHT instead of the identified construct to be measured (e.g., memory, abstraction, decision making) is not clear. To help distinguish "motor" effects from these more complex "cognitive" effects, neuropsychological data on 70 adult PHT monotherapy patients were reanalyzed. Initially, a series of statistically significant differences favored the low serum level group over the high serum level group in neuropsychologic performance. However, when a simple measure of motor speed (Finger Tapping Test) was covaried out, all statistically significant differences between the groups disappeared. Thus, losses in cognitive abilities could not be associated with PHT even though markedly elevated blood levels had been achieved.

Psychosocial dimensions of epilepsy: a review of the literature

The literature on psychosocial dimensions of epilepsy has been reviewed utilizing the framework developed by Dodrill et al. (Epilepsia 1980; 21:123-35). Factors considered were family background, emotional adjustment, interpersonal adjustment, vocational adjustment, financial status, adjustment to seizures, and medicine and medical management. The published studies highlighted a number of issues and sometimes rendered varying and contradictory conclusions. In general, epilepsy fosters certain reactions in family members. If negative, these reactions may be detrimental to the person with epilepsy. The association between specific emotional adjustment factors and epilepsy is not conclusive. Studies have been published which support as well as refute this association. Studies indicate that persons with epilepsy experience lower rates of marriage and more sexual difficulties than do nonepileptic persons. Studies report greater unemployment and underemployment in epileptic persons than in the population at large. Studies suggest that some persons with epilepsy manifest an attitude of nonacceptance of self. Some are reluctant to disclose their disability to others. The studies also indicate the presence of a discriminatory attitude by some nonepileptic persons toward epileptic persons. Several factors are associated with successful medical management of epilepsy. The emphasis in research studies with regard to psychosocial aspects of epilepsy focuses predominantly on individual deficiencies rather than on strengths and abilities.

Academic achievement of children with epilepsy

The academic achievement scores of 122 children with epilepsy were examined in relation to demographic and clinical seizure variables. As a group, these children were making less academic progress than expected for their age and IQ level. Academic deficiencies were greatest in arithmetic, followed by spelling, reading, comprehension, and word recognition. Results of the multiple regression analyses indicated a modest combined predictive significance of the demographic and clinical seizure variables for academic performance. In addition, the magnitude of these relationships varied by academic area. Among the individual variables examined the strongest correlates of academic performance were age of the child, age of seizure onset, lifetime total seizure frequency, and presence of multiple seizures (absence and tonic-clonic). These results are discussed in relation to developing an understanding of the factors which underlie academic vulnerability in children with epilepsy.