The study group encompassed 179 patients (92 M, 51.5%) followed at our Unit of Child Neuropsychiatry and aged between 4 and 25 years (mean + SD: 14.03 卤 4.25). The inclusion criteria included the following: 1) diagnosis of epilepsy of 鈥渦nknown cause鈥?(cryptogenic) according to the ILAE classification, 2) age older than 3 years, 3) stabilized antiepileptic treatment for at least 6 months, and 4) clinical records of cognitive tests, plasma tHcy value, and results of MTHFR polymorphisms. Patients' mean tHcy value was 9.71 卤 3.13 渭M/L (tHcy < 9 渭M/L as our laboratory cutoff in nonepileptic controls). The mean TIQ score was 85.22 (SD 卤 24.12); the mean VIQ score was 86.32 (SD 卤 20.86); and the mean PIQ score was 86.94 (SD 卤 21.51). C677T and A1298C MTHFR polymorphisms were detected in 74/92 (80%) examined patients and distributed into the following: CT (22.3%), TT (14.9%), CC (10.3%) for C677T, AC (16%), CC (1.1%), and AA (30.3%) for A1298C.
Plasma tHcy levels were not significantly related to the IQ scores (TIQ, VIQ, or PIQ). Two significant findings came out. First, patients on AED polytherapy showed significantly lower TIQ, VIQ, and PIQ scores compared with the ones with AED monotherapy (p = 0.032; p = 0.008; p = 0.005, respectively). However, this significant difference was not observed with the plasma tHcy levels compared with AED treatment. Second, patients with the 677TT genotype showed significantly higher tHcy levels versus those with the wt ones (p = 0.049). In the latter group of patients, although the mean TIQ score was lower compared with the mean TIQ score in those with the wt ones, the difference only approached statistical significance (p = 0.056). To our knowledge, this is the first study investigating the relationship between tHcy levels and cognitive scores in children with epilepsy treated with AEDs. Analysis of wider samples, selective neuropsychological tests, and prospective recruitment of patients might be encouraged.