Plasma Plasminogen Activator Inhibitor-1 as a Biomarker for Disease Activity and Pharmaco-Response Prediction in Pediatric Epilepsy: A Prospective Cohort Study

Purpose: To investigate the clinical relevance of plasma plasminogen activator inhibitor-1 (PAI-1) in pediatric epilepsy, focusing on its associations with seizure severities and therapeutic outcomes. Methods: We conducted a prospective cohort study to compare the plasma PAI-1 levels quantified by ELISA across children with active epilepsy, seizure-free patients, and healthy controls. Furthermore, subgroup analyses were conducted to assess the impact of AED treatment or long-term drug response to the plasma PAI-1 levels. Results: PAI-1 levels were 2.1-fold higher in the seizure group than in the control group ( p < 0.0001), and 1.3-fold higher than in remission patients ( p < 0.0001). No significant difference was observed between the anti-epileptic drug-treated and untreated subgroups ( p = 0.0689). Baseline PAI-1 levels predicted 12-month pharmaco-responses, with pharmaco-resistant patients showing 12% higher PAI-1 concentrations than responders ( p = 0.0234). Conclusion: Our findings establish plasma PAI-1 as a promising biomarker for identifying children at high risk for pharmaco-resistant epilepsy, thereby addressing a high-burden condition. The persistence of PAI-1 elevation hints at underlying inflammatory or synaptic pathologies that may be novel therapeutic targets beyond conventional AEDs.