Detecting epilepsy‐related cognitive problems in clinically referred children with epilepsy: Is the WISC‐IV a useful tool?

Abstract

Summary Purpose: The Wechsler Intelligence Scale for Children – Fourth Edition is the most widely used intelligence quotient (IQ) test in use today. However, despite numerous studies on IQ in childhood epilepsy, data exist almost exclusively from prior editions of the test, and no studies to date provide information on the sensitivity of specific WISC‐IV scores (full‐scale IQ [FSIQ], index, and subtest scores) to epilepsy‐related cognitive impairments. The goal of this study was to determine the relative sensitivity of WISC‐IV index and subscale scores in detecting cognitive problems in a group of clinically referred children with epilepsy compared to matched controls, and to define the relationship among WISC‐IV scales, demographic factors, and epilepsy‐related variables. Methods: WISC‐IV data for children with epilepsy and high seizure burden were obtained from the Alberta Children’s Hospital (ACH) and the New York University Comprehensive Epilepsy Center (NYU), two tertiary care medical centers for pediatric epilepsy. All children were clinically referred and received a standard assessment including WISC‐IV. Matched controls were obtained from the WISC‐IV Canadian and American standardization samples. Key Findings: WISC‐IV scores from 212 children were included: 106 children with epilepsy (46 girls, 60 boys; mean age 11.0 years, standard deviation [SD] 3.1; parental education 14.5 years, SD 2.8), and 106 controls matched for age, gender, ethnicity, and parental education. Of the children with epilepsy, 44 had a clearly lateralized focus on electroencephalography (EEG) involving either the right or left hemisphere (26 left, 18 right). FSIQ for the epilepsy group was significantly lower than for controls, and 36.8% of children had IQs compatible with intellectual disability (FSIQ < 70), versus <1% of controls. In children with epilepsy, Working Memory and Processing Speed Index scores were lower than those for Verbal Comprehension and Perceptual Reasoning (p < 0.01). At the subtest level, scores for children with epilepsy were highest on visual and verbal subtests measuring reasoning skills such as Matrix Reasoning, and lowest on Coding (mean 5.93, SD 3.6). In terms of percentage of children on each subtest with low scores (i.e., scores below 2 SDs from the expected normative mean of 10), the Coding subtest identified the most children (28.3%) with low scores, and the Similarities subtest identified the fewest (16%). Later age at onset and shorter epilepsy duration were both correlated with higher WISC‐IV FSIQ and index scores (r correlation coefficient values ranging from 0.36 to 0.44, p < 0.0001), and number of current and previous antiepileptic drug trials were both inversely correlated with FSIQ and index scores (r −0.27 to −0.47, all p‐values < 0.01). Neither the FSIQ nor the index scores were significantly related to seizure frequency. A similar pattern was found for subtest scores. No differences in FSIQ, index scores, or subtest scores were found between children with left‐ and right‐hemisphere seizur...

Long-term neurocognitive outcome and auditory event-related potentials after complex febrile seizures in children

“…Symbol Search is a subtest measuring processing speed and visual attention, suggesting that the primary difficulty for children relates to complex attention and working memory and not to motor speed [29]. Matrix reasoning is a subtest of the PRI; therefore, our results suggest a deficit in reasoning and abstraction in the verbal and visual modalities of children with complex FS.…”

“…Difficulties in Processing Speed and Working Memory were the most prominent in Table 4 Event-related potential (ERP) latencies (msec) in controls and in groups with different types of febrile seizures. children with epilepsy [29]. Long-term psychological studies have documented that the chronic effect on declarative memory systems in patients with epilepsy and cumulative cognitive impairment increase with the duration of seizures [32][33][34].…”

Neuropsychological Endophenotypes in ADHD With and Without Epilepsy

“…It is well established that those with ADHD-I may show slow response speeds (Diamond, 2005), and it has been shown that ''sluggish cognitive temp'' is strongly related to the DSM-IV constructs of inattention (Hartman, Willcutt, Rhee, & Pennington, 2004). It is perhaps then not surprising that those with epilepsy and ADHD-I would show even slower response speeds, given the fact that processing-speed deficits are common in epilepsy (Dow, Seidenberg, & Hermann, 2004;Pascalicchio et al, 2007;Sherman, Brooks, Fay-McClymont, & MacAllister, 2012). Moreover, many AEDs have cognitive slowing as a side effect (Loring & Meador, 2004).…”

Attention and Executive Functions in Children With Epilepsy: What, Why, and What to Do

“…For example, age of epilepsy onset is a robust predictor of overall cognitive dysfunction across numerous studies (Berg et al, 2008;Farwell et al, 1985;O'Leary et al, 1983;Schoenfeld et al, 1999;Sherman, Brooks, Fay-McClymont, & Macallister, 2012). Likewise, high seizure frequency (Bourgeois, Prensky, Palkes, Talent, & Busch, 1983;Farwell et al, 1985;Sherman et al, 2012), multiple seizure types (e.g., generalized seizures [generalized tonic-clonic seizures, absence seizures], partial-complex seizures), and the need for more than one antiepileptic drug (Bourgeois et al, 1983;Bulteau et al, 2000;Sherman et al, 2012) have been associated with greater cognitive dysfunction. It is also important to recognize that specific antiepileptic medications have more or less favorable side-effect profiles and may adversely impact cognition (Loring, Marino, & Meador, 2007;Loring & Meador, 2004;).…”