# Analysis of treatment outcome variations in infantile epileptic spasms syndrome

## TL;DR

This study examines factors affecting treatment outcomes in children with infantile epileptic spasms syndrome, finding that genetic causes and treatment combinations influence responses.

## Contribution

The study identifies genetic and non-genetic factors influencing treatment outcomes and evaluates the efficacy of combined therapies in infantile epileptic spasms syndrome.

## Key findings

- Children with genetic causes showed poorer responses to ACTH and vigabatrin compared to those without genetic causes.
- Combining ACTH with vigabatrin improved outcomes in some children with IESS.
- Non-ACTH treatment groups showed better EEG improvement outcomes than ACTH-treated groups.

## Abstract

To explore the key factors influencing outcomes in children with infantile epileptic spasms syndrome (IESS) and to elucidate their interrelationships to provide insights for optimizing clinical practice.

This is a retrospective, single-center design study, included children diagnosed with IESS at West China Second Hospital of Sichuan University from April 2019 to April 2024. Descriptive analyses were performed to evaluate genetic and non-genetic etiological subgroups, categorized as structural and unknown causes. Genetic testing results were compared across groups. Pearson correlation and logistic regression analyses were employed to examine differences in treatment efficacy and identify associated risk factors.

In this study, 128 children diagnosed with IESS were enrolled and evenly divided into gene-positive and gene-negative groups. The gene-positive group exhibited earlier seizure onset, with a higher prevalence of hypotonia and developmental regression compared to the gene-negative group. Within the gene-negative group, children were further categorized into structural abnormality and unknown causes subgroups, among which EEG hypsarrhythmia was more frequently observed in the structural abnormality subgroup. The gene-positive group showed significantly poorer responses to ACTH, vigabatrin, and other ASMs. ACTH combined with vigabatrin therapy improved outcomes in some of the children. The non-ACTH treatment group demonstrated superior EEG improvement outcomes when compared with the ACTH-treated group (p = 0.028). The overall therapeutic response rate was satisfactory, with 75% in the gene-positive group and 100% in the gene-negative group. In the gene-negative group, frequent seizures and developmental regression emerged as significant risk factors for poor treatment response.

The prognosis for IESS remains challenging, with treatment responses closely tied to etiology. Children with genetic etiologies demonstrate poorer responses to ACTH and other ASMs. However, ACTH combination with vigabatrin may improve treatment outcomes in some cases. Our findings suggest that ACTH treatment may not exert a substantial influence on long-term EEG outcomes in children with IESS.