Homocysteine levels in epileptic children receiving antiepileptic drugs

The Study of Carotid Artery Intima-Media Thickness in Children With Epilepsy on Anti-Epileptic Drugs

Objectives. To evaluate carotid artery intima-media thickness (CIMT) and lipid profile in children with epilepsy on long-term antiepileptic drug (AED) monotherapy. Methods. We included 60 children with epilepsy receiving valproate, carbamazepine, or levetiracetam monotherapy and 60 controls. A high-resolution B-mode ultrasound was used to measure (CIMT). Measurement of serum lipids was done. Results. Patients on valproate (0.44 ± 0.03, P ≤ .001), carbamazepine (0.43 ± 0.03with P ≤ .001), and levetiracetam (0.44 ± 0.02 with P ≤ .001) monotherapy showed significantly higher CIMT compared to controls. CIMT was correlated with age (P = .041, r = .112) AEDs{valproate (P = .005, r = .731), carbamazepine (P = .038, r = .365), and levetiracetam (P = .036, r = .155)}, duration of treatment (P = .001, r = .313), TC(P = .001, r = .192), TG (P = .014, r = .018), and LDL (P = .001, r = .219). HDL (P = .003, r = -.126). Seizure severity and Apo A1 were insignificantly involved. Conclusion. Long-term monotherapy with valproate, carbamazepine, and levetiracetam in epileptic children was associated with significant abnormalities in CIMT.

Influence of Different Antiseizure Medications on Vascular Risk Factors in Children with Epilepsy

Many studies have proposed that plasma homocysteine levels are increased as a side effect with the prolonged use of antiseizure medications. This is associated with an increase in carotid intima media thickness; hence, it increases the threat of atherosclerosis at a young age. We aimed to assess serum levels of homocysteine in epileptic children on long-standing antiseizure medications and its association with increased occurrence of cardiovascular disease. The study included 60 epileptic children aged between 2 and 15 years old who visited our pediatric neurology outpatient clinic and 25 apparently healthy children served as a control group. All included children were subjected to careful history taking, clinical examination, anthropometric measures, laboratory investigations including serum homocysteine levels and lipid profile, along with radiological assessment involving carotid intima media thickness and carotid stiffness. Results demonstrated a significant increase in the serum levels of homocysteine, carotid intima media thickness, and carotid stiffness in children on monotherapy of old generation antiseizure medications and polytherapy than that in children on monotherapy of new generation antiseizure medications and control children. Epileptic children on old generation and polytherapy antiseizure medications have an increased risk for cardiovascular diseases and need follow up for early intervention when needed.

Pharmacokinetics and Pharmacogenetics of Carbamazepine in Children

Although carbamazepine is one of the oldest anticonvulsant drugs, it is still heavily utilized for treatment of epilepsy in children. The aim of this article was to review the current knowledge about pharmacokinetics and pharmacogenetics of carbamazepine in children. The literature for this review was systematically searched for in the MEDLINE and SCINDEKS databases. Oral bioavailability of carbamazepine in children is about 75-85%, and it is approximately 75-85% bound to plasma proteins. Apparent volume of distribution is 1.2-1.9 l/kg and total clearance between 0.05 and 0.1 l/h/kg. Pharmacokinetics of carbamazepine in children is age and body weight dependent and highly variable due to influence of dosing regimen and co-medication. The current evidence on the importance of pharmacogenetics for carbamazepine efficacy and safety in children supports the association of PXR*1B, HNF4a rs2071197, CYP1A2*1F, ABCC2 1249G>A, and PRRT2 c.649dupC with either pharmacokinetics or pharmacodynamics of carbamazepine. The importance of human leukocyte antigen (HLA) typing for prediction of adverse drug reactions to carbamazepine in children is also confirmed. Both genetic and environmental factors are responsible for shaping pharmacokinetics and pharmacodynamics of carbamazepine in children. To ensure safe and effective use of carbamazepine in this population, physicians should adjust dosing regimen according to existing pattern of genetic and environmental influences.

Effect of Folic Acid Supplementation on Seizure Control in Epileptic Children Receiving Long Term Antiepileptic Therapy

OBJECTIVE

To evaluate the effect of folic acid supplementation on seizure control in folate deficient children receiving long term antiepileptic therapy.

METHODS

In a prospective interventional study, 140 children between age group 6 mo to 180 mo fulfilling the inclusion criteria were enrolled in study group, from October 2015 through November 2016. On the basis of serum folate, study group was divided into two subgroups by non randomization: Group A (<10 ng/ml) given folic acid supplementation for 3 mo and Group B (>10 ng/ml) was not supplemented. Response to folic acid supplementation in group A was compared with group B in terms of change in blood folate levels, frequency and duration of seizures after three months.

RESULTS

Mean age of study group was 73.58 ± 46.89 mo (72.14% boys and 27.85% girls). 67.85% children were in group A and 32.14% in group B. On 3 mo follow up, children supplemented with folic acid (Group A) had significant fall in mean seizure frequency while in non-supplemented children (Group B), no significant change was seen (p value <0.05). Similar reduction in duration of seizure episode was seen in group A as compared to group B. Serum and RBC folate levels improved from baseline in group A, while in group B there was significant fall in folate levels.

CONCLUSIONS

Folate deficiency is common in epileptic children on long term antiepileptic drugs (AEDs), contributes to poor seizure control and should be considered in the etiologic differentials of drug resistant epilepsy. Folate supplementation improves seizure control in these children.

Effects of Antiepileptic Drugs on the Carotid Artery Intima-Media Thickness in Epileptic Patients

BACKGROUND AND PURPOSE

It has been reported that taking antiepileptic drugs (AEDs) may increase the risk of atherosclerosis. We performed a meta-analysis to evaluate the carotid artery intima-media thickness (CA-IMT) as a surrogate factor for atherosclerosis in epileptic patients.

METHODS

We searched NCBI (PubMed), ISI Web of Knowledge, EMBASE, and the Cochrane Library databases for studies of the association between AEDs and CA-IMT in epileptic patients. A random-effects meta-analysis was used to pool results across studies.

RESULTS

Fifteen studies involving 1,775 epileptic patients were included in the analysis. The overall CA-IMT was significantly larger among users of AEDs [mean difference (MD)=0.09 mm, 95% confidence interval (CI)=0.06-0.12 mm). When stratified by age, the MD was similar in adult patients (MD=0.09 mm, 95% CI=0.06-0.13 mm), but no significant difference was observed in children (MD=0.03 mm, 95% CI=0.00-0.07 mm). Regarding specific AEDs, monotherapy with carbamazepine (CBZ) or valproic acid (VPA) was associated with a larger CA-IMT, while phenytoin monotherapy was not and the result for lamotrigine was inconclusive.

CONCLUSIONS

This study suggests that using AEDs is associated with the CA-IMT in patients with epilepsy, particularly for adult patients. In particular, CBZ and VPA may be related to a significant increase in CA-IMT.

Hyperhomocysteinaemia in children receiving phenytoin and carbamazepine monotherapy: a cross-sectional observational study

OBJECTIVE

Long-term therapy with phenytoin and carbamazepine is known to cause hyperhomocysteinaemia. We evaluated the prevalence of hyperhomocysteinaemia in North Indian children receiving phenytoin or carbamazepine monotherapy for >6 months duration and the effect of folic acid supplementation on plasma homocysteine.

METHODS

In this cross-sectional observational study we enrolled consecutive children aged 2-12 years with epilepsy who had received phenytoin or carbamazepine monotherapy for >6 months. Plasma total homocysteine, folic acid, vitamin B12 and antiepileptic drug concentrations were measured. Healthy age- and sex-matched controls were recruited. Children with homocysteine >10.4 µmol/L received folic acid supplementation for 1 month and homocysteine and folic acid concentrations were measured after 1 month follow-up.

RESULTS

A total of 112 children receiving antiepileptic monotherapy for >6 months were enrolled. Hyperhomocysteinaemia was present in 54 children (90%) receiving phenytoin, 45 children (90%) receiving carbamazepine therapy and 17 (34%) controls (p<0.05). Mean plasma homocysteine concentrations were significantly higher (18.9±10.2 vs 9.1±3 µmol/L) and serum folic acid concentrations (10.04±8.5 ng/ml vs 12.6±4.8 p<0.001) and vitamin B12 concentrations (365±155 pg/mL vs 474±332 pg/mL, p=0.02) were significantly lower in the study group compared with the control group. Duration of antiepileptic drug therapy correlated significantly with elevated homocysteine and reduced folic acid concentrations (p<0.05). Supplementation with folic acid for 1 month led to a reduction in plasma homocysteine concentrations in the study group (from 20.9±10.3 µmol/L to 14.2±8.2 µmol/L, p<0.05).

CONCLUSIONS

Phenytoin or carbamazepine monotherapy for >6 months duration is associated with hyperhomocysteinaemia in 90% of North Indian children. Elevated homocysteine concentrations were normalised in these children with folic acid supplementation.

Oxcarbazepine administration and the serum levels of homocysteine, vitamin B12 and folate in epileptic patients: A systematic review and meta-analysis

The objectives were to determine the influence of oxcarbazepine (OXC) monotherapy on the serum levels of total homocysteine (tHcy), vitamin B12 and folate in patient with epilepsy pooling together case-control or interventional studies. A comprehensive literature search was done through four databases including MEDLINE/PubMed, Scopus, Embase and Web of Science from January 2000 to February 2016. A random effects model (the DerSimonian-Laird estimator) was utilized to pool the effect sizes of the individual studies. The between-study variance was assessed using the Q2 test (significance level p<0.1) and quantified using the I² test (>50% indicated evidence of heterogeneity). Overall, six studies found eligible for inclusion. The meta-analysis for tHcy revealed that the serum level of tHcy was no significant difference between patient on OXC monotherapy and healthy people [mean difference (MD) 0.31; 95% CI -1.05, 1.67, p=0.653]. The meta-analysis for vitamin B12 [MD -46.51; 95% CI -113.63, 20.62, p=0.174] and folate [MD -0.48; 95% CI -1.06, 0.11, p=0.113] indicated that there was no significant difference between patients on OXC monotherapy and healthy people. In conclusion, the meta-analysis does not support the hypotheses that OXC monotherapy changes the serum levels of tHcy, vitamin B12 and folate.

Increased homocysteine levels in valproate-treated patients with epilepsy: a meta-analysis

OBJECTIVE

To determine whether valproate (VPA) monotherapy influences homocysteine metabolism in patients with epilepsy.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

We searched all articles in English through PubMed, Web of Science and EMBASE published up to August 2013 concerning the homocysteine levels in VPA monotherapeutic patients with epilepsy.

PARTICIPANTS

VPA-treated patients with epilepsy (n=266) and matched healthy controls (n=489).

OUTCOME MEASURES

Heterogeneity between studies was assessed using I(2) statistics. Pooled standardised mean difference (SMD) and 95% CIs were calculated using a random effect model.

RESULTS

A total of eight eligible studies were enrolled in our meta-analysis. We compared the plasma levels of homocysteine in VPA-treated patients with epilepsy and healthy controls. There was significant heterogeneity in the estimates according to the I(2) test (I(2)=65.6%, p=0.005). Plasma homocysteine levels in VPA-treated patients with epilepsy were significantly higher than in healthy controls under a random effect model. (SMD, 0.62; 95% CI 0.32 to 0.92). Further subgroup analyses suggested that no significant differences were present when grouped by ethnicity and age, but the risk of heterogeneity in the West Asian group (I(2)=47.4%, p=0.107) was diminished when compared with that of the overall group (I(2)=65.6%, p=0.005).

CONCLUSIONS

Our meta-analysis indicates that VPA monotherapy is associated with the increase in plasma homocysteine levels in patients with epilepsy. Whether this association is influenced by ethnicity needs further research.

Evaluation of Homocysteine, Folic Acid and Vitamin B12 Levels among Egyptian Children with Idiopathic Epilepsy

Objective: To evaluate relationship between homocysteine (Hcy), folic acid and vitamin B12 with anti-epileptic drugs in epileptic patients and their role in epilepsy control.Patient and Methods: The study included 60 patients with idiopathic epilepsy and thirty non-epileptic children of the same age and sex served as controls. All cases were subjected to physical and neurological examination and electroencephalogram (EEG). Serum level of folic acid, homocysteine (Hcy) and vitamin B12 were done for both epileptic patients and controls. Non parametric test, one way ANOVA and Pearson’s correlation were used for analysis of data.Result: 44 patients (73.3%) had generalized epilepsy and the remaining patients had partial epilepsy (simple or complex). 37 patients (61.6%) were in grade I, 3 patients (5 %) were in grade II and the remaining 20 patients (33.3 %) were in grade III epilepsy. Vitamin B12 was significantly higher in epileptic patients. Duration of anti-epileptic drug treatment was correlated significantly to folic acid and Hcy level.Conclusion: antiepileptic drugs might upset the homeostatic balance of Hcy and its cofactors and cause abnormalities of their serum levels. The duration of anti-epileptic drug treatment was related to decrease of folic acid and increase in homocysteine levels.

Role of plasma homocysteine levels and MTHFR polymorphisms on IQ scores in children and young adults with epilepsy treated with antiepileptic drugs

Homocysteine (Hcy) is a sulfur-containing amino acid involved in methionine metabolism. High plasma total Hcy (tHcy) has been quite frequently reported in patients with epilepsy treated with antiepileptic drugs (AEDs) mainly related to plasma folate reduction induced by AEDs themselves. The role of C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase gene (MTHFR) on the increase of plasma tHcy in patients with epilepsy taking AEDs is still controversial. Cognitive impairment may be associated with epilepsy either as the result of the epileptic syndrome per se or as a side effect induced by the AEDs. High plasma tHcy levels were associated with lower cognitive performances in patients affected by Alzheimer's disease and mild cognitive impairment and in healthy elderly. We searched for a correlation between plasma tHcy levels with the intelligence quotient (IQ) scores in a population of children and young adults with epilepsy treated with old and/or newer AEDs. The study group encompassed 179 patients (92 M, 51.5%) followed at our Unit of Child Neuropsychiatry and aged between 4 and 25years (mean+SD: 14.03±4.25). The inclusion criteria included the following: 1) diagnosis of epilepsy of "unknown cause" (cryptogenic) according to the ILAE classification, 2) age older than 3years, 3) stabilized antiepileptic treatment for at least 6months, and 4) clinical records of cognitive tests, plasma tHcy value, and results of MTHFR polymorphisms. Patients' mean tHcy value was 9.71±3.13μM/L (tHcy<9μM/L as our laboratory cutoff in nonepileptic controls). The mean TIQ score was 85.22 (SD±24.12); the mean VIQ score was 86.32 (SD±20.86); and the mean PIQ score was 86.94 (SD±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.

The role of hyperhomocysteinemia in neurological features associated with coeliac disease

Although a range of neurological and psychiatric disorders are widely reported to be associated with coeliac patients, their pathogenesis remains unclear. Some such disorders are believed to be secondary to vitamin deficiency due to malabsorption, others to immune mechanisms. We hypothesise that hyperhomocysteinemia might, by damaging the blood-brain barrier, expose neuronal tissue to all neuro-irritative metabolites, such as homocysteine itself, a neurotoxic excitatory and proconvulsant amino acid. Neurons respond to these stimuli through hyperexcitability, thereby predisposing subjects to neurological disorders such as epilepsy and headache. Furthermore, persisting endothelial damage may cause blood extravasation and subsequent deposition of calcium salts. We suggest that this might be the pathogenesis of the CEC syndrome, which is characterized by the association of coeliac disease, epilepsy and cerebral calcifications. Indeed, homocysteine plays a well-known role in cardiovascular endothelial dysfunction, with high serum and cerebrospinal fluid levels often being reported in coeliac patients. Moreover, data in the literature show a strong, growing association of homocysteine with epilepsy and migraine in non-coeliac subjects. Despite these findings, homocysteine has never been held directly responsible for neuronal functional features (neuronal hyperexcitability underlying epilepsy and migraine) and structural brain damage (expressed as cerebral calcification) in coeliac patients. Damage to the blood-brain barrier might also facilitate immune reactions against neuronal tissue to a considerable extent. This hypothesis combines the two afore-mentioned theories (vitamin deficiency due to malabsorption and immune mechanisms). We also wish to point out that no studies have yet investigated the prevalence of neuronal hyperexcitability and subclinical electroencephalic abnormalities in children and adults with newly-diagnosed coeliac disease before the introduction of a gluten-free diet, and in particular any changes following the introduction of the diet. We believe that the onset of clinical symptoms such as migraine and convulsions is preceded by a period in which damage is expressed exclusively by subclinical electroencephalic abnormalities; persisting damage to neuronal tissue subsequently leads to clinical manifestations. We propose two types of investigations: the first is to determine whether newly-diagnosed coeliac patients with hyperhomocysteinemia are a subgroup at risk for neurological features (clinical and subclinical); the second is to determine whether appropriate treatment of hyperhomocysteinemia and vitamin B status deficiency improves neurological abnormalities and reduces the risk of cerebral calcifications. The aim of these investigations is to develop new therapeutic strategies designed to prevent neuronal damage and increase the quality of life in children affected by such disorders.

Effect of carbamazepine therapy on homocysteine, vitamin B12 and folic acid levels in children with epilepsy

OBJECTIVE

To compare the levels of homocysteine, vitamin B12 and folic acid before and after 6 months of carbamazepine therapy and to correlate them with carbamazepine level at 6 months.

DESIGN

Prospective comparative study.

SETTING

Tertiary care centre in North India.

PARTICIPANTS

51 children (2-12 years of age) presenting with motor partial seizures.

INTERVENTION

Carbamazepine (10-20 mg/kg/day) for 6 months.

MAIN OUTCOME MEASURE

Change in serum homocysteine, B12, folic acid level.

METHODS

Fasting venous samples were collected before carbamazepine therapy and after six months. Homocysteine was analyzed using homocysteine enzyme immunoassay. Vitamin B12 and folic acid were estimated using electrochemiluminesence technique. Carbamazepine levels were measured at 6 months.

RESULTS

Of the 51 children, 36 (males-21), were followed up and their data analyzed. Mean homocysteine level was 11.51±3.95 umol/L at recruitment and 11.77±6.65 umol/L at six months (P=0.785). At recruitment 6(16%) children had homocysteine level above 15 umol/L which increased to 10(27%) at 6 months. Mean vitamin B12 at recruitment was 292.1±111.2 pg/mL and 297.8±82.9 pg/mL at 6 months (P=0.764). Mean folic acid at recruitment was 9.98±3.45 ng/mL and 10.66±3.97 ng/mL at 6 months (P=0.358). There was no correlation between carbamazepine levels with homocysteine, vitamin B12 and folic acid (P>0.05). There was no effect of age, sex or dietary pattern on homocysteine levels.

CONCLUSIONS

Hence 6 months of carbamazepine therapy did not cause significant change in serum levels of homocysteine, vitamin B12 and folic acid.

Osguei N, Effatkhah M, Samadikuchaksaraei A. Serum level of homocysteine, folate and vitamin-B12 in epileptic patients under carbamazepine and sodium valproate treatment: a systematic review and meta-analysis

Background

Numerous studies have shown that long term treatment with anticonvulsants may be an important risk factor for the onset of atherosclerosis, or worsening of its symptoms. There are many contradictory reports regarding these effects.

Objectives

We performed a systematic review and meta-analysis of the published studies in order to see whether the atherogenic outcomes could be related to any serum biochemical abnormalities.

Materials and Methods

Published articles indexed in PubMed, ISI web of science, Science Direct and Scopus databases from 1990 to 2011 were retrieved using a comprehensive search strategy. After omitting the unrelated articles and duplicates, articles met the eligibility criteria for critical appraisal were included in the analysis. Data were summarized in standard data abstraction forms and subjected to analysis by STATA software.

Results

Finally, ten published studies were included in the meta-analysis. Results showed that carbamazepine and sodium valproate consumption are associated with a significant elevation of the serum homocysteine levels. On the other hand, medication with carbamazepine is associated with a reduction of the level of folate in the serum and that of sodium valproate is associated with a reduction of serum level of vitamin B12.

Conclusions

According to the results of this study, as carbamazepine and valproate sodium consumption can result in elevated serum levels of homocysteine and decreased levels of folate and vitamin B12, and the atherogenic effect of increased serum homocysteine level is well established, the patients under these medications should be monitored for possible atherogenic effects.

Assessment of atherosclerosis risk due to the homocysteine-asymmetric dimethylarginine-nitric oxide cascade in children taking antiepileptic drugs

PURPOSE

The aim of this study was to assess the atherogenicity risk of antiepileptics in children by investigating the cascade, "hyperhomocysteinemia (HHcy)→asymmetric dimethylarginine (ADMA) increase→nitric oxide (NO) decrease", which is thought to contribute to the developmental process of atherosclerosis.

METHODS

The participants included 53 epilepsy patients who received either valproic acid (VPA, n=26) or oxcarbazepine (OXC, n=27). Twenty-four healthy sex- and age-matched children served as controls. Fasting plasma total homocysteine (tHcy), ADMA and NO levels were measured.

RESULTS

The differences in Hcy, ADMA, NO, vitamin B(12) and folate levels between VPA, OXC and control groups were all insignificant (p>0.05 for all). In the patient group (VPA and OXC groups), 22.6% of the children (12/53) had tHcy levels above the normal cutoff (13.1μmol/l) for children and 17% of the children (9/53) had tHcy levels of greater than 15μmol/l which is accepted as the critical value for an increased atherosclerosis risk (p<0.05 for both). The difference in rate of HHcy between VPA and OXC groups was statistically insignificant (p>0.05, for both cut off levels of HHCy). There was a positive correlation of tHcy levels and antiepileptic drug treatment duration in the patient group (r=+0.276, p<0.05).

CONCLUSION

HHcy may develop in patients using OXC. Contrary to some previous publications, our data do not suggest that OXC is safer than VPA in terms of HHcy risk. Further prospective, large scale and longer term studies investigating all suggested pathways responsible for development of atherosclerosis due to HHcy should be conducted to define the exact mechanism responsible for AEDs related atherosclerosis.

Role of folic acid depletion on homocysteine serum level in children and adolescents with epilepsy and different MTHFR C677T genotypes

Homocysteine (Hcy) is a sulfur-containing amino acid involved in methionine metabolism. An elevated total plasma Hcy concentration (tHcy) is a risk factor for vascular disease. The present study aimed to assess the role of antiepileptic drugs (AEDs) and C677T methylenetetrahydrofolate (MTHFR) polymorphisms on tHcy in pediatric patients with epilepsy treated for at least 6 months with various treatment regimens protocols including the newer AEDs. The study group was recruited from children and adolescents with epilepsy followed up in the Child Neuropsychiatry Clinic of the Second University of Naples, between January 2007 and March 2008. Inclusion criteria were: (1) patients with epilepsy, treated with one or more anticonvulsant drugs for at least 6 months; (2) age between 2 and 16 years. Plasma tHcy concentrations were considered elevated when they exceeded 10.4 μmol/L, and folate concentrations <3 ng/mL were considered deficient. Serum vitamin B12 levels were considered normal between 230 and 1,200 pg/mL. The study group was composed of 78 patients (35 males, 43 females), aged between 3 and 15 years (mean 8.9 years). Thirty-five patients were taking AED monotherapy, 43 polytherapy. Sixty-three healthy sex- and age-matched children and adolescents served as controls. The mean tHcy value in the patient group was higher than the mean value in the control group (12.11 ± 7.68 μmol/L vs 7.4±4.01 μmol/L; p<0.01). DNA analysis for the MTHFR C677T polymorphism showed the CT genotype in 46%, CC in 35% and TT in 17.8% of cases. Decreased folic acid serum levels significantly correlated with increased tHcy levels (p<0.003). Female sex was a less significant risk factor for increased tHcy levels (p=0.039). Our study confirms the association between hyperhomocysteinemia and epilepsy. The elevation of tHcy is essentially related to low folate levels. Correction of poor folate status, through supplementation, remains the most effective approach to normalize tHcy levels in patients on AED mono- or polytherapy.