Homocysteine (HMC) is a sulfur containing amino acid, which plays a role in methionine metabolism. Folic acid (FA) and vitamin B12 (B12) are essential for remethylization of HMC to methionine. HMC level increases in the deficiency of these vitamins. Hyperhomocysteinemia causes vascular endothelial damage, which causes atherosclerosis. The aim of this study is to investigate the effect of valproate (VA) and carbamazepine (CBZ) on the serum levels of HMC, B12, and FA. Thirty-six children receiving CBZ and 30 children receiving VA for epilepsy for the last 1-year period and 29 healthy children as control were the population of this study. After 6 h of fasting serum HMC, B12, and FA levels were measured and results were compared statistically. Mean values of HMC, FA, and B12 levels in control group were 9.2±2.7 μmol/l, 9.0±2.0 ng/ml, and 342±162 pg/ml, in VA group 14.0±6.8 μmol/l, 7.3±2.9 ng/ml, and 368±159 pg/ml, in CBZ group 16.0±13.1 μmol/l, 7.5±3.3 ng/ml, and 285±158 pg/ml, respectively. Serum HMC levels were higher in VA and CBZ groups than control group (P<0.01 and P<0.05, respectively). Serum FA levels were lower in VA and CBZ groups compared to control group (P<0.05). Serum levels of B12 were not different between VA and control groups (P>0.05). In CBZ group serum B12 levels were lower than control group (P<0.05). FA may be added to the treatment protocol (if the patients take only CBZ, then B12 should also be added) for patients taking these antiepileptic drugs to decrease the degenerative effect of VA and CBZ on vascular endothelium. © 2002 Elsevier Science B.V. All rights reserved.
Indications:30 children with epilepsy.
Patients:66 patients aged 2-16 years. Tegretol group: n=30, 18 boys and 12 girls. VA group: n=36, 14 boys and 22 girls. 29 healthy children (17 boys and 12 girls) served as controls.
TypeofStudy:An open, controlled, comparative study investigating the effect of Tegretol and valproic acid (VA) on the serum levels of homocysteine (HMC), vitamin B12 (B12), and folic acid (FA) in epileptic children.
DosageDuration:Dosage not stated. Duration: at least 1 year.
ComparativeDrug:Valproic acid dosage not stated. Duration: at least 1 year.
Results:Mean HMC levels were significantly higher both in Tegretol and VA groups than the control group (16 and 14 versus 9.2 mcmol/l, P < 0.05). Hyperhomocysteinemia was noted in 7 (23.3%) patients in the Tegretol group and 11 (30.5%) in the VA group. FA levels were significantly lower in the Tegretol and VA groups than the control group (7.5 and 7.3 versus 9.0 ng/ml, P < 0.05). No difference was noted between the 2 groups on HMC and FA levels. B12 levels were lower in the Tegretol group compared with the VA and control groups (285.2 versus 368 and 343 pg/ml, P < 0.05).
AdverseEffects:7 patients had hyperhomocysteinemia. Unspecified number had increased serum levels of homocysteine and decreased serum levels of FA and B12.
AuthorsConclusions:In conclusion, our data demonstrate that fasting plasma HMC concentrations significantly increased in children taking VA or CBZ [carbamazepine]. Administration of these drugs also induces a decrease in serum levels of FA. We advise to measure HMC levels in all patients treated with these AEDs [antiepileptic drugs]. Addition of FA to the antiepileptic therapy to prevent vascular diseases may be useful in patients receiving VA or CBZ. Similarly serum B12 levels might be measured due to the possibility of a significant decrease in B12 levels in CBZ receiving patients and if necessary B12 may be added to the treatment.
FreeText:Tests: fasting serum levels of HMC, B12, and FA.