Long-term Neuropsychological Trajectories in Pediatric Epilepsy Patients: Can Surgery Prevent Decline?

Patients with long-term drug-resistant epilepsy (DRE) often face severe neuropsychological functional impairments, especially in children, which can significantly impact their academic performance, social relationships, and future employment opportunities. The background of this research area stems from several previous studies showing significant cognitive decline in patients due to factors such as the onset of epilepsy and the use of antiseizure medications (ASMs). However, previous research results on the effectiveness of epilepsy surgery in alleviating these cognitive impairments have been inconsistent. Therefore, the authors of this study, Maria H. Eriksson et al., attempted to explore the impact of epilepsy surgery on long-term neuropsychological function in children through systematic long-term follow-up.

This study was conducted by researchers from several renowned institutions, including Great Ormond Street Hospital for Children, UCL Great Ormond Street Institute of Child Health, and UCL Queen Square Institute of Neurology. The article was published in the April 2024 issue of “Brain” and is available through open access.

Research Methods

Study Subjects and Dataset

The research team collected data from 882 pediatric patients who underwent epilepsy surgery at Great Ormond Street Hospital between 1990 and 2018. Using a retrospective cohort study method, researchers selected 500 patients who had undergone at least one pre-operative or post-operative neuropsychological assessment. Patients’ neuropsychological function was primarily assessed through IQ tests (including full-scale IQ, verbal IQ, performance IQ, working memory, and processing speed) and academic achievement tests (including reading, spelling, and math abilities).

Research Process

Neuropsychological Assessment

The research team included various IQ testing tools such as the Wechsler Intelligence Scale for Children (WISC), Wechsler Preschool and Primary Scale of Intelligence (WPPSI), Wechsler Adult Intelligence Scale (WAIS), and Wechsler Abbreviated Scale of Intelligence (WASI). Additionally, academic achievement testing tools included the Wechsler Individual Achievement Test (WIAT), Wechsler Objective Reading Dimensions (WORD), Wechsler Objective Numerical Dimensions (WOND), and Wide Range Achievement Test (WRAT).

Data Processing and Statistical Analysis

Researchers extracted and standardized scores from various patient tests. To verify changes in patients’ neuropsychological function before and after surgery, the research team employed multiple statistical methods, including linear regression analysis and mixed-effects models.

Research Results and Analysis

Pre-operative Neuropsychological Trajectories

The study found that children undergoing epilepsy surgery showed significant declines in all neuropsychological functional domains before surgery. Both cross-sectional and longitudinal analyses showed cognitive deterioration throughout the pre-operative period. For example, the average annual decline in Full-scale IQ (FSIQ) was -1.9, Verbal IQ (VIQ) was -1.6, and Performance IQ (PIQ) was -1.1.

Post-operative Neuropsychological Trajectories

Post-operative assessments showed no significant overall change in patients’ neuropsychological scores. However, further detailed results revealed that patients who became seizure-free after epilepsy surgery showed trends of improvement in cognitive function during long-term follow-up. For instance, post-operative full-scale IQ increased by 0.9 points annually, with these improvements being particularly significant for patients who discontinued antiseizure medications.

Sample Characteristics and Clinical Presentations

Patients with multiple neuropsychological assessments before and after surgery showed longer epilepsy duration and higher initial cognitive levels, suggesting that earlier cognitive foundations may play an important role in functional recovery after surgery.

Classification and Prediction Models

The study showed that patients with higher pre-operative IQ had better post-operative recovery. Additionally, factors such as seizure history, types, and frequency of antiseizure medications significantly affected patients’ neuropsychological performance both pre- and post-operatively. Through continuous observation and classification of these factors, the research team attempted to develop models that could more accurately predict post-operative seizure control and cognitive recovery.

Conclusions and Significance

Research Findings

The study indicates that epilepsy surgery has a significant impact on the neuropsychological function of children with drug-resistant epilepsy. By achieving complete cessation of seizures through surgery and gradual discontinuation of antiseizure medications, patients’ cognitive function can significantly improve and even reverse pre-operative cognitive decline.

Clinical Applications

Based on the research results, researchers suggest considering and performing epilepsy surgery as early as possible for children with focal epilepsy to minimize or avoid cognitive deterioration. This study provides important empirical evidence and data support for clinical physicians in treatment option selection and counseling for patients’ families.

Methodological Innovation

The study employed comprehensive analysis methods using long-term, large-sample tracking and multiple assessment data, providing a new perspective to address issues of data reliability and conclusion consistency in previous small-scale, short-term studies.

Through this research, the academic community has gained a more comprehensive understanding of the role of epilepsy surgery in improving cognitive function in children, providing strong support for future clinical practice and research.