Functional seizures: Cluster analysis may predict the associated risk factors.

Area of Science:

• Neurology
• Psychiatry
• Clinical Epidemiology

Background:

• Functional seizures (FS) are a common diagnosis in epilepsy clinics.
• Understanding the heterogeneity of FS and associated risk factors is crucial for effective management.
• Previous research has not fully elucidated distinct patient subgroups within FS based on clinical and demographic factors.

Purpose of the Study:

• To apply Two-Step cluster analysis to a large cohort of patients diagnosed with functional seizures (FS).
• To investigate whether background risk factors differ among identified patient clusters.
• To explore the relationship between demographic/clinical characteristics and risk factors in FS.

Main Methods:

• Two-Step cluster analysis was performed on 230 patients with FS who reported risk factors.
• Analysis considered age at onset, sex, and seizure semiology.
• Associated risk factors, including history of sexual and physical abuse, were examined across clusters.

Main Results:

• Three distinct patient clusters emerged from the analysis.
• Cluster 1 was characterized by akinetic seizures.
• Cluster 2 featured motor seizures without ictal injury, while Cluster 3 had motor seizures with ictal injury. A history of sexual abuse was more prevalent in Cluster 1 compared to Cluster 3 (OR: 3.26).
• A history of physical abuse was less common in Cluster 2 compared to Cluster 3 (OR: 0.45).

Conclusions:

• Two-Step cluster analysis successfully identified three distinct patient clusters in FS based on demographic and clinical features.
• These clusters demonstrated significant correlations with associated risk factors, particularly histories of abuse.
• Findings highlight the importance of considering distinct subgroups and associated trauma in the comprehensive understanding and treatment of FS.