Plasma levels of glial fibrillary acidic protein and placental growth factor are associated with drug resistance in adult patients with newly diagnosed epilepsy.

OBJECTIVE: The study aims to examine the plasma levels of glial fibrillary acidic protein (GFAP) and placental growth factor (PGF) in adult patients with epilepsy and investigate their association with drug resistance after exposure to antiseizure drugs (ASDs). METHODS: The study included 80 patients with newly diagnosed epilepsy and 80 non-epileptic controls. The seizure control of patients was evaluated at 12 months after commencement of the initial ASD regimen. Seizure freedom was defined as a period without seizures for 12 months or 3 times the longest pretreatment seizure-free interval (whichever was longer). Drug resistance was defined as continued seizures despite at least two adequate trials of ASDs. RESULTS: Patients developing drug resistance showed higher pretreatment levels of plasma GFAP and PGF than those achieving seizure freedom and non-epileptic controls (one-way analysis of variance: P < 0.001). Group × time interactions were significant in GFAP [linear mixed-effects model (LMM) analysis: P = 0.021) and PGF (LMM analysis: P = 0.012). Based on LMM analysis, the differences of post-treatment levels of GFAP and PGF between patients achieving seizure freedom and those developing drug resistance were -650 pg/ml (95%CI, -823 to -476) and -4.80 pg/ml (95%CI, -6.06 to -3.54), respectively. The plasma GFAP, plasma PGF, and their combination in predicting drug response presented AUC: 0.78, 0.81, and 0.88, respectively. CONCLUSION: Our findings suggest plasma GFAP and PGF may be associated with drug resistance in adult patients with newly diagnosed epilepsy.