Homocysteine, folate, vitamin B-12 and vitamin B-6 in patients receiving antiepileptic drug monotherapy

Food supplement vitamins, minerals, amino-acids, fatty acids, phenolic and alkaloid-based substances: An overview of their interaction with drugs

Food supplements are a widespread group of products ingested as a diet complement, whose consumption has recently skyrocketed due to the consumers' concern with their well-being. Among food supplements, vitamin- and mineral-based ones are the top sellers, and the demand of others, such as those containing polyphenols, is increasing. Owing to their alleged natural characteristics, consumers take the safety of food supplements for granted, and use them even when taking medicines. Thus, their potential interactions with drugs have been sparsely evaluated. This manuscript aims to bring forth an up-to-date overview of the most important knowledge involving the interactions between food supplements and drugs, relevant to be aware by nutritionists and other healthcare professionals. To this end, an extensive bibliographic review was conducted focusing on peer reviewed data from experimental in vivo evidence and clinical studies whenever major clinical interactions have been reported. Elder people and polymedicated or chronic patients are especially vulnerable to the therapeutic ineffectiveness and toxicity caused by these types of interactions. Drugs used to treat cardiovascular, autoimmune, nervous, and oncological diseases are commonly involved in important clinical interactions with food supplements, many with a narrow therapeutic margin.

Association of folic acid, vitamin B12, and intelligence scores in epileptic children

Epilepsy is a serious childhood disease associated with cognitive impairment. Our aim was to investigate the possible association of serum folic acid, vitamin B12, and intelligence scores in epileptic children. A group of 30 children with established diagnosis of idiopathic epilepsy for at least one year as well as another group of 30 nonepileptic healthy children as the control group were recruited for analysis. Cognitive performance was assessed by a battery of psychological tests that covers verbal and nonverbal intelligence. Serum B12 level was significantly lower in patients than the control group (264.17 ± 58.07, 450.55 ± 134.9, respectively). No significant difference was detected between patients and the control group regarding serum folic acid level. Verbal, performance, and total IQ were significantly lower in patients than the control group (83.2 ± 3.08 vs. 95.8 ± 6.22, 78.4 ± 10.68 vs. 91.3 ± 2.45, and 180.6 ± 6.58 vs. 93.5 ± 3.02, respectively). However, no significant correlation was detected in folic acid, vitamin B 12, and cognitive scores. Epileptic children were five times more at risk of having low IQ (verbal, performance, and total) < 85 than the control group (OR = 4.754, 95% CI 13.047-1031.316, p = .000). In conclusion, children with epilepsy might be at higher risk for cognitive dysfunction than normal children. No significant association was detected between cognitive performance and either folic acid or vitamin B12 in epileptic children receiving sodium valproate. Supplementation of those vitamins should be restricted to those with documented deficiency.

Antiepileptic drug-induced psychosis associated with MTHFR C677T: a case report

Background

Various antiepileptic drugs can potentially cause psychiatric side effects in patients with epilepsy, but the precise mechanism of these actions remains unknown. In recent years, the common polymorphism C677T in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene has attracted attention for its role in the onset of psychiatric diseases. MTHFR and several vitamins (as cofactors) are crucial for remethylation of homocysteine via folate and homocysteine metabolism. We report a case of a Japanese patient who presented with reversible schizophrenia-like symptoms during antiepileptic drug therapy.

Case presentation

Our patient had frontal lobe epilepsy and had been treated with several antiepileptic drugs since the age of 13 years. He developed auditory hallucinations and multiple personalities at 17 years of age, several months after the initiation of phenytoin and phenobarbital, despite these antiepileptic drugs being used within the therapeutic ranges. Genetic analysis revealed that he was homozygous for the C677T polymorphism of MTHFR. Hyperhomocysteinemia, hypomethionemia, and multiple vitamin deficiencies, including folate, riboflavin, and pyridoxal, were identified at the age of 23 years. Vitamin supplementation and alteration of the antiepileptic drugs improved his psychotic symptoms. Multiple vitamin deficiencies with homozygous MTHFR C677T should be considered in patients presenting with schizophrenia-like symptoms during antiepileptic drug therapy.

Conclusions

To the best of our knowledge, this is the first report of antiepileptic drug-induced psychosis associated with homozygous C677T and multiple vitamin deficiencies. Our findings will contribute to the elucidation of the pathogenesis of the psychiatric side effects of antiepileptic drugs and lead to improved medical management for patients with epilepsy.

Vitamin B12 and Folate Status in Patients with Epilepsy Under Levetiracetam Monotherapy

Background:

Antiepileptic drugs (AEDs) may lead to an increase in the plasma concentration of homocysteine. There is limited information, especially from Iran, regarding the risk in patients who are treated with levetiracetam as a new type of AED. The aim of the present study was to investigate the effect of levetiracetam on plasma homocysteine, vitamin B12, and folate levels in adult patients with epilepsy.

Methods:

We conducted a case-control study and enrolled adult patients with epilepsy who had received monotherapy with levetiracetam for at least 6 months at some time prior to the study. homocysteine serum, vitamin B12, and folate were measured, and folate and vitamin B12 intake was determined by the food frequency questionnaire (FFQ).

Results:

Thirty-three patients on levetiracetam and 35 control subjects aged between 18 and 60 years were enrolled. No statistically significant differences in the means of the serum markers of vitamin B12, FA, and homocysteine levels were found between the two groups. In the first model, i.e., the crude model, no significant differences were observed in the serum concentrations of homocysteine, vitamin B12, and folate. In the second model, education was considered, and body mass index and folate intake was controlled with no significant difference being observed in the mean homocysteine serum level.

Conclusions:

Treatment with levetiracetam in patients with epilepsy has no effect on the serum levels concentrations of homocysteine, vitamin B12, and folate. This medication is suggested for patients who use AEDs on a long-term basis and at high dosages.

Medicines associated with folate-homocysteine-methionine pathway disruption

Folate is vital for cell development and growth. It is involved in one-carbon transfer reactions essential for the synthesis of purines and pyrimidines. It also acts in conjunction with cobalamin (vitamin B₁₂) as a fundamental cofactor in the remethylation cycle that converts homocysteine to methionine. A deficiency in folate or vitamin B₁₂ can lead to elevated homocysteine level, which has been identified as an independent risk factor in several health-related conditions. Adequate folate levels are essential in women of childbearing age and in pregnant women, and folate deficiency is associated with several congenital malformations. Low folate levels can be caused by dietary deficiencies, a genetic predisposition or treatment with medicines that affect folate concentration. Women who are pregnant or of child-bearing age commonly use medicines, so it is important to identify the basic biochemical mechanisms by which medicines interfere with the folate-homocysteine-methionine pathway. This review focuses on prescription medicines associated with folate disruption. It also summarizes their undesirable/toxic effects. Recommendations regarding folate supplementation during medical therapy are also reviewed.

L-Methylfolate For Bipolar I depressive episodes: An open trial proof-of-concept registry

BACKGROUND

L-methylfolate is a compelling candidate to treat bipolar I major depressive episodes. While approved as an adjunct for unipolar major depressive disorder, no studies have been done to assess the tolerability, safety, and efficacy of L-methylfolate for bipolar depression. As a first step, we developed a registry of bipolar patients treated with L-methylfolate to examine tolerability and outcomes.

METHODS

Subjects (N=10) received treatment as usual plus daily L-methylfolate 15mg for 6 weeks in this open-label registry. Depressive symptoms were assessed with the Montgomery Asberg Depression Rating Scale (MADRS) and manic symptoms with the Young Mania Rating Scale (YMRS). Effect size was measured with Cohen's d to provide an estimate of potential efficacy.

RESULTS

The pre-treatment mean (SD) MADRS score was 23.4 (4.34); the post-treatment score was 13.9 (8.24). Cohen's d was 1.19. At post-treatment, 6/10 patients had at least 50% MADRS improvement, and 4/10 patients exhibited remission with MADRS≤10. The pre-treatment YMRS score was 3.2 (3.0); the post-treatment score was 2.7 (5.2). Cohen's d was 0.17.

LIMITATIONS

This registry was a small open-label clinical trial for a fluctuating disorder. We cannot rule out that our results are due to regression to the mean. A controlled trial is warranted.

CONCLUSIONS

This first proof-of-concept open registry suggests that L-methylfolate in combination with treatment as usual has potential to treat bipolar depression.

Periconceptional folic acid supplementation among pregnant women with epilepsy in a developing country: a retroprospective survey in China

OBJECTIVE

The aims of this study were to investigate the implementation of guidelines on periconceptional folic acid supplementation among pregnant women with epilepsy (WWE) in China and to identify its potential correlations with selected sociodemographic and clinical factors.

METHODS

A detailed investigation was conducted in China using a structured questionnaire from December 2013 to May 2014. Data on the awareness and use of folic acid supplementation, as well as sociodemographic and clinical characteristics, were collected from 153 pregnant WWE. Descriptive analysis, followed by univariate and multivariate logistic regression analyses, was applied to the data from this survey.

RESULTS

Among the enrolled subjects, 67.3% became pregnant after the promulgation of the relevant guidelines. Only 26.2% of them knew the exact effects of folic acid, and 73.8% had taken folic acid at some point during periconception. In addition, the folic acid intake of most of these women (67.1%) did not exceed that of the average pregnant woman. The prevalence of folic acid supplementation for pregnant WWE three months before pregnancy was only 15.5%. There has been almost no improvement in the level of additional awareness and use of folic acid supplementation for WWE since the relevant guidelines were established in China. Pregnant WWE with higher education levels, those with a planned pregnancy, or those who live in urban areas were more likely to know about and implement folic acid supplementation during periconception. Moreover, pregnant WWE with a planned pregnancy or those living in cities seemed to have a higher folic acid intake and started folic acid supplementation earlier before conception.

CONCLUSION

The extent of awareness and use of folic acid supplementation in pregnant WWE remains low in China. More efforts are needed to promote periconceptional folic acid supplementation for WWE, especially those with low education levels and those who live in rural areas. Planned pregnancy should be encouraged for WWE.

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.

One-carbon metabolism and bipolar disorder

OBJECTIVE

Folate is one of the most widely used nutraceuticals for the treatment of mood disorders. In this article, we review folate metabolism, its relationship with bipolar disorder, and its therapeutic potential.

METHODS

We searched PubMed and the Cochrane Library for relevant articles up to and including the year 2012. Background information, proposed mechanisms of action, and results from clinical trials were reviewed.

RESULTS

Folate is an essential cofactor involved in methylation reactions, which are critical for monoamine synthesis and homocysteine regulation. Folate level is thought to be associated with mood disorders and limited response to antidepressants. Functional deficiency, due to a common genetic variant of the methylenetetrahydrofolate reductase (NAD(P)H) (MTHFR) gene, could also affect the presentation of bipolar disorder. Sodium valproate and lamotrigine, commonly used mood stabilizers for the treatment of bipolar disorder, can potentially interfere with folate and homocysteine metabolism. Previous studies consistently support the efficacy of folate in the treatment of depression; one study showed efficacy in the treatment of mania. Biologically active forms of folate formulations, which do not require biochemical conversion, could be beneficial in the treatment of bipolar disorder.

CONCLUSIONS

Folate augmentation could be effective for the treatment of bipolar disorder. A common genetic variant of the MTHFR gene might impact the treatment effect of folate augmentation. The biologically active form of folate could potentially correct mood stabilizer-associated functional folate deficiency, help normalize monoamine synthesis, and improve outcomes.

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.

B-vitamin deficiency in patients treated with antiepileptic drugs

Enzyme-inducing antiepileptic drugs (AEDs) produce many alterations in metabolism, including vitamin levels. Whether they produce clinically relevant deficiency of B vitamins has rarely been assessed. We obtained B-vitamin levels in patients who were being converted from an inducing AED (phenytoin or carbamazepine) to a non-inducing AED (levetiracetam, lamotrigine, or topiramate), with measurements both before and ≥ 6 weeks after the switch. A group of normal subjects underwent the same studies. Neither folate nor B12 deficiency was seen in any patient. Vitamin B6 deficiency was found in 16/33 patients (48%) taking inducers, compared to 1/11 controls (9%; p=0.031). After switch to non-inducers, only 7 patients (21%) were B6 deficient (p=0.027). The incidence of deficiency was similar regardless of which inducing or non-inducing AED was being taken. Our findings demonstrate that treatment with inducing AEDs commonly causes pyridoxine deficiency, often severe. This could conceivably contribute to the polyneuropathy sometimes attributed to older AEDs, as well as other chronic heath difficulties.

Antiepileptic drugs and vitamin B6 plasma levels in adult patients

Treatment with several antiepileptic drugs (AED) is associated with lower serum concentrations of folate or vitamin B12. This prospective monocenter study analyzed vitamin B6 blood levels in 400 serial patients with epilepsy, AED-treated (n=385), untreated (n=15) and healthy controls (n=233). The mean plasma vitamin B6 levels of the AED-treated (12.1±10.1; p=0.093) and the untreated patients (15.6±12.4; p=0.664) were not significantly different from the controls (13.9±15.2). These observations do not support the hypothesis that vitamin B6 blood levels are influenced by AED treatment.

The effect of vitamin B supplementation on homocysteine metabolism and clinical state of patients with chronic epilepsy treated with carbamazepine and valproic acid

PURPOSE

To investigate the influence of vitamin B supplementation on the plasma total homocysteine (p-tHcy), serum folate (s-FA), serum B12 (s-B12), and clinical state of patients with chronic epilepsy.

METHODS

Beck Depression Inventory (BDI) scores and p-tHcy, s-B12, and s-FA levels were assessed at baseline, after 1 year of supplementation (G1), and before and after 1 year of VPA or CBZ therapy (G2).

RESULTS

Eighty-one patients participated in the study: 51 patients with chronic epilepsy (G1) treated with carbamazepine (CBZ) or valproic acid (VPA), and 30 patients with newly diagnosed epilepsy (G2). At baseline, mean p-tHcy level was significantly higher in G1 than G2 (p=0.0001) with no significant differences in s-FA or s-B12 levels. p-tHcy level significantly decreased in CBZ-treated G1 patients (p=0.00002) after 1 year of supplementation and increased in G2 after 1 year of anti-epileptic drug (AED) therapy without supplementation. BDI scores in G1 decreased significantly after 1 year of supplementation (p=0.0001) and increased significantly in VPA-treated G2 patients after 1 year of AED therapy (p=0.02). The number of hyperhomocysteinemic patients significantly decreased in G1 after vitamin B supplementation (p=0.01) and increased in G2 (p=0.002). We also observed improved BDI scores and reduced seizure frequency in patients with chronic epilepsy.

CONCLUSIONS

These data support the hypothesis that AEDs play a major role in hyperhomocysteinemia development in patients with epilepsy. Adding folate and vitamin B12 to AED therapy is a safe and inexpensive way to reduce the risk of hyperhomocysteinemia.

Bisphosphonates in phenytoin-induced bone disorder

Chronic administration of phenytoin (PHT) has been associated with bone loss. Bisphosphonates [alendronate (ALD), ibandronate (IBD) and risedronate (RSD)] are potential candidates to prevent PHT-induced bone disorders, and the present study evaluated their effect on the antiepileptic efficacy of PHT. The PHT-induced depletion in folic acid (FA), vitamin B6 and vitamin B12 results in hyperhomocysteinemia. The elevated circulating homocysteine (hcy) could be a risk indicator for micronutrient-deficiency-related osteoporosis via generation of free radicals. Thus, an attempt was also made to unravel the PHT's and bisphosphonates' effect on hcy. Male mice received PHT (35 mg/kg, p.o.) for 90 days to induce bone loss. ALD, RSD and IBD were administered orally at doses 0.65 mg/kg, 0.33 mg/kg, and 0.17 mg/kg respectively, for prevention and 1.3mg/kg, 0.65 mg/kg, and 0.33 mg/kg respectively, for treatment of PHT-induced bone loss. The bone loss was confirmed by bone mineral density (BMD) analysis and bone turnover markers. Serum levels of hcy and FA were estimated along with hydrogen peroxide levels and total antioxidant capacity in order to assess the antioxidant profile of bisphosphonates. The induction of bone loss by PHT was marked by lowered BMD and altered bone turnovers. ALD and RSD administration to PHT treated groups significantly reverted the bony adverse effects. No such effects were observed with IBD. In the bisphosphonates treated groups, hcy levels were statistically at par with the control group. PHT at 35 mg/kg, p.o. could compromise bone mass and thus, could be a model of bone demineralization in mice. The ALD, IBD and RSD have no pharmacodynamic interaction when administered along with PHT at the experimental level. Thus, their usage in the management of PHT-induced bone disease could be worthwhile if clinically approved.

Effect of antiepileptic drugs and reactive oxygen species on folate receptor 1 (FOLR1)-dependent 5-methyltetrahydrofolate transport

Metabolic breakdown of valproate (VPA), carbamazepine (CBZ) and phenytoin (PHT) by the cytochrome P450 pathway generates toxic drug intermediates and reactive oxygen species (ROS). This mechanism has been suspected to play a role in the pathogenesis of secondary cerebral folate deficiency (CFD). Using KB-cell cultures, highly expressing the folate receptor 1 (FOLR1), the effect of antiepileptic drugs (AEDs) and reactive oxygen species (ROS) on the FOLR1 dependent 5-methyltetrahydrofolate (MTHF) uptake was studied. MTHF uptake is time and concentration dependent and shows saturation kinetics. At physiological MTHF concentrations the high-affinity FOLR1 represents the predominant mechanism for cellular incorporation, while at high MTHF concentrations other transport mechanisms participate in folate uptake. Exposure to PHT for more than 8h led to a higher MTHF uptake and decreased cell count, whereas MTHF uptake remained unaltered by VPA and CBZ. However, exposure to superoxide and hydrogen peroxide radicals significantly decreased cellular MTHF uptake. By specific elimination and downregulation of FOLR1 using phosphatidyl-inositol-specific phospholipase C (PIPLC) and siRNA silencing, it was shown that ROS not only inhibited FOLR1 mediated MTHF uptake but also affected all other mechanisms of membrane-mediated MTHF uptake. Generation of ROS with the use of AED might therefore provide an additional explanation for the disturbed folate transfer across the blood-CSF barrier in patients with CFD.

The effects of oxcarbazepine treatment on vitamin B12 and folate levels, thyroid functions, sex hormones, and bone mineral density in epileptic patients

The aim of this study was to evaluate vitamin B12 and folate levels, thyroid functions, sex hormones and bone mineral density in idiopathic epileptic patients taking oxcarbazepine as monotherapy. Newly diagnosed pediatric patients with idiopathic partial epilepsy taking oxcarbazepine (OXC) as monotherapy were enrolled in this study. The pre-treatment and 6 months post-treatment values of vitamin B12, folate, thyroid functions, sex hormones, and bone mineral density (BMD) were obtained from all patients. A total of 32 patients (22 (68.8%) males and 10 (31.2%) females) were included in this study. The mean age was 7.4 ± 3.2 years (range: 2–14 years). There were no significant differences between the pre-treatment and 6 months post-treatment values of vitamin B12, folate, thyroid functions, sex hormones, and BMD. However, the 6 month post-treatment sex hormone binding globulin (SHBG) values (159.92 ± 48.14 nmol/L) were significantly higher than the pre-treatment values (137.88 ± 43.12 nmol/L) (p=0.009). We found that OCX treatment in children did not have an effect on serum folate and vitamin B12 levels, thyroid functions, sex hormones and BMD but caused increased SHBG. Over time, the increase in serum SHBG levels may lead to diminished bioactivity of sex steroids, and thus to reduced fertility. The further studies are needed to demonstrate the clinical importance of increased SHBG levels.

Homocysteine level in schizophrenia patients

OBJECTIVE

Elevated serum levels of homocysteine have been shown to be associated with schizophrenia in some studies, but the evidence is still limited and mixed. The aim of the present study was therefore to evaluate the serum homocysteine level in Chinese in schizophrenia patients and assess its association with clinical phenotypes of the disease.

METHOD

A total of 250 inpatients and 250 healthy controls were identified at Kowloon Hospital and the Red Cross Blood Donation Centre, respectively. Each subject was evaluated with a structured diagnostic interview. Demographic data were collected and blood was analysed for homocysteine level. The Positive and Negative Syndrome Scale was used to grade clinical symptoms of schizophrenia. Confounding factors affecting homocysteine levels were controlled by strict exclusion criteria or statistical methods.

RESULTS

Serum homocysteine level was elevated in Chinese schizophrenia patients. Both male (mean, 12.26 micromol L(-1); control, 11.40 micromol L(-1), p = 0.026) and female (mean, 9.61 micromol L(-1); control, 8.33 micromol L(-1), p < 0.001) patients had a higher serum homocysteine level than the healthy controls, and these differences persisted after controlling for age. There was no significant association between serum homocysteine level and duration of illness, clinical symptoms or age of onset of schizophrenia.

CONCLUSION

The serum homocysteine levels were elevated in both male and female Chinese schizophrenia patients. The levels were not apparently related to other clinical parameters.

Spontaneous abortion and the prophylactic effect of folic acid supplementation in epileptic women undergoing antiepileptic therapy

BACKGROUND

Antiepileptic drugs (AEDs) like phenytoin (PHE), carbamazepine (CBZ), barbiturates and valproic acid (VPA) interfere with folic acid absorption and metabolism, which in turn can be the cause of adverse pregnancy outcome.

OBJECTIVE

To study the prophylactic effect of folic acid supplementation with regard to spontaneous abortion and preterm delivery (fetal demise after week 20 of gestational age) in pregnant women receiving AED therapy, as well as benefits of most common dosage and preconceptional commencement.

METHODS

Prospective examination of 104 patients, registered in EURAP from 1999-2004 at a single center and a retrospective analysis of data from our epilepsy databank completed with medical records and patients interviews of the Department of Neurology of Innsbruck University Hospital from 1971 to 1999.

RESULTS

388 pregnancies in 244 patients were analyzed. Pregnancies with folic acid supplementation showed significant reduction of spontaneous abortion. With regard to monotherapies, in the group of women taking VPA, supplementation of folic acid had significant benefit. Other examined monotherapies (CBZ, PHE, and PB) known to interfere with folic acid showed no significant results.

CONCLUSIONS

This study confirms the prophylactic effect of folic acid supplementation on spontaneous abortion. For AED therapy, folic acid supplementation should be part of the therapy of every pregnant epileptic woman, especially for those treated with VPA.

Evaluation of the relationship between C677T variants of methylenetetrahydrofolate reductase gene and hyperhomocysteinemia in children receiving antiepileptic drug therapy

Homocysteine (Hcy) is a sulfur-containing amino acid involved in methionine metabolism. Elevated plasma Hcy concentration is a possible risk factor for vascular disease. Folate and vitamin B-12 are vitamins that are necessary for remethylization of Hcy to methionine. The methylenetetrahydrofolate reductase (MTHFR) is the key enzyme in remethylation of Hcy to methionine and supplies the required 5-methyltetrahydrofolate as the methyl donor for this reaction. It is well known that some antiepileptic drugs (AED) can lead to hyperhomocysteinemia by affecting the levels of folate and vitamin B-12. The C677T variant of MTHFR gene can also lead to hyperhomocysteinemia particularly when serum folate level is decreased. In this study, we investigated the levels of serum folate, vitamin B-12 and Hcy in epileptic patients receiving carbamazepine (CBZ) or valproic acid (VPA) as monotherapy, and we also evaluated the probable contribution of the C677T variant of MTHFR gene in hyperhomocysteinemia. A total of 93 patients with idiopathic epilepsy receiving CBZ or VPA as monotherapy were included in this study. CBZ and VPA groups consisted of 29 and 64 patients, respectively. The control group comprised 62 healthy children. We measured serum folate, vitamin B-12 and Hcy levels in each group. We found that mean serum folate level was statistically lower and mean Hcy level was higher in epileptic patients receiving CBZ or VPA when compared with those of controls'. We also determined the C677T variants of MTHFR gene (as normal, heterozygote or homozygote) in epileptic patients. We compared the variant groups for serum folate, vitamin B-12 and Hcy levels and found no significant differences among them. In conclusion, C677T variants of MTHFR gene have no contribution in hyperhomocysteinemia in epileptic patients receiving CBZ or VPA.

Homocysteine levels in epileptic children receiving antiepileptic drugs

The aim of this study is to investigate the homocysteine, folic acid, and vitamin B(12) levels in epileptic children receiving antiepileptic drugs. A total of 25 children with idiopathic epilepsy (8 valproate, 11 carbamazepine, and 6 oxcarbazepine) and 10 healthy children were included in the study. The mean homocysteine, folic acid, and vitamin B(12) levels in the study group were 7.57 +/- 3.78 micromol/L (normal = 5-15 micromol/L), 10.19 +/- 4.05 ng/mL (normal = 3.0-17 ng/mL), and 428.20 +/- 256.12 pg/mL (normal = 193-983 pg/mL), respectively. The differences between the mean plasma homocysteine, folic acid, and vitamin B(12) levels of the study and control groups were not significant (P = .522; P = .855; P = .798, respectively). However, plasma homocysteine levels were higher than the normal cutoff point accepted for childhood in 4 (16%) of the study patients. Out of these 4 children, 3 were from the carbamazepine group and 1 was from the valproate group. Although the number of the study patients is limited, the authors recommend assessment of plasma homocysteine, serum vitamin B(12), and folic acid levels in children receiving enzyme-inducing antiepileptic drugs.

Growing old with epilepsy: the neglected issue of cognitive and brain health in aging and elder persons with chronic epilepsy

The purpose of this review is to examine what is known about cognitive and brain aging in elders with chronic epilepsy. We contend that much remains to be learned about the ultimate course of cognition and brain structure in persons with chronic epilepsy and concern appears warranted. Individuals with chronic epilepsy are exposed to many risk factors demonstrated to be associated with abnormal cognitive and brain aging in the general population, with many of these risk factors present in persons with chronic epilepsy as early as midlife. We suggest that a research agenda be developed to systematically identify and treat known modifiable risk factors in order to protect and promote cognitive and brain health in aging and elder persons with chronic epilepsy.

Antiepileptic drugs and MTHFR polymorphisms influence hyper-homocysteinemia recurrence in epileptic patients

The influence of antiepileptic drugs (AEDs) and/or common polymorphisms (677C --> T, 1298A --> C) of the methylene-tetrahydrofolate-reductase (MTHFR) gene on the recurrence time of hyper-total-homocysteinemia (tHcy > 13 micromol/L) was investigated in 59 hyper-homocysteinemic patients (34M/25F, 20-49 years). Plasma tHcy and folate were assayed before and after 1-month folate supplementation (5 mg/day), and after 2, 4, and 6 months. Four MTHFR polymorphism groups were identified with the following tHcy (micromol/L) and folate (nmol/L) levels (mean +/- SD): (a) MTHFR677TT/1298AA, 24 patients, 36.0 +/- 4.8, 4.1 +/- 0.7; (b) MTHFR677CT/1298AC 27.1 +/- 2.7, 5.3 +/- 1.0 (n = 15); (c) MTHFR677CT/1298AA 16.6 +/- 3.6, 6.8 +/- 1.0 (n = 11), all taking enzyme-inducing AEDs; and (d) MTHFR677TT/1298AA 24.5 +/- 3.2, 5.6 +/- 1.1 (n = 9), treated with new AEDs. After folate therapy, plasma t-Hcy and folate were normal in all patients. At 6 months, 43 patients (72.9%) exhibited hyper-tHcy, the greater proportion belonging to the EI-AED-MTHFR677TT/1298AA (39%). Knowledge of the hyper-tHcy recurrence time after folate therapy discontinuation may help in optimizing folate supplementation pulses.

Folate status in women of childbearing age with epilepsy

Treatment with cytochrome P450 enzyme-inducing antiepileptic drugs (P450-inducing AEDs) is known to interfere with folate metabolism. Low folate status is of special concern in women with epilepsy who might become pregnant. Therefore, folate status was assessed in women age 16-42 treated for epilepsy. Staple food is not folic acid fortified in Norway. Only 1/94 women was folate-deficient by the laboratory reference value for serum folate of > 4 nM. Fourteen (15%) patients with serum folate values from 5 to 9 nM may be considered folate-insufficient. Plasma homocysteine was elevated > 13 microM in 2/65 women. These findings compare favorably with previous reports. A questionnaire addressing factors interfering with folate metabolism was answered by 58 of the women. In women who did not use a supplement containing > or =0.2 mg of folic acid regularly (n=33), the median serum folate value was lower in those using P450-inducing AEDs than in those using other AEDs (p=0.023). The interaction between P450-inducing AEDs and folate metabolism may be clinically relevant and can be balanced by supplementation of small doses of folic acid. The results of this survey support the recommendation that women of childbearing age treated with AEDs receive folic acid supplementation, particularly those taking P450-inducing AEDs.

Rehabilitation of the Older Adult with Stroke

Stroke is an increasing public health concern throughout the world as the leading cause of long-term disability. It is well known that there exist differences related to epidemiology, pathophysiology, comorbidity, and functional outcome of stroke patients with advanced age compared with the young. Factors that have been suggested to influence this disparity include age-related complications, availability of resources, lack of aggressive management, and possible diminished capacity for neuroplasticity. This article reviews the current medical and rehabilitative aspects of stroke and the possible disparities related to advanced age.

Nutritional and life style determinants of plasma homocysteine in schizophrenia patients

Recently, homocysteine levels have been reported to be elevated in young male schizophrenic patients. Since smoking, obesity, low folate or low vitamin B12 and various medications can increase homocysteine levels, we studied these variables and other clinical variables in 258 schizophrenic patients. A multiple linear regression for plasma homocysteine was performed on variables that were significantly related to plasma homocysteine. Variables predicting homocysteine levels in schizophrenic patients include gender, plasma folate levels, plasma vitamin B12 levels, mean red blood cell corpuscular volume and diastolic blood pressure. Only 24% of the variance in male patients was explained by the model. The reason for elevated plasma homocysteine in some schizophrenic populations remains unclear.

Blood homocysteine, folate and Vitamin B-12 concentrations in patients with epilepsy receiving lamotrigine or sodium valproate for initial monotherapy

To evaluate whether the administration of lamotrigine (LTG) or valproate (VPA) changes concentrations of plasma total homocysteine (tHcy), plasma and red-cell folate and plasma Vitamin B-12, we measured these indices in a total of 20 patients with epilepsy before and after a 32-week period of monotherapy of LTG or VPA. We found that the 32-week administration of a mean daily dose of 250mg LTG had no significant effect on any of the blood indices. On the other hand, the administration of a mean daily dose of 2070mg of VPA resulted in a 57% increase in plasma Vitamin B-12 concentrations over the baseline value and a 27% decline in plasma tHcy concentrations, although the mechanisms of such changes are unknown. Our data indicate that hyperhomocysteinemia may not be a serious clinical problem among patients with epilepsy, who receive either LTG or VPA.

Teratogenicity of sodium valproate

The teratogenicity of the widely popular antiepileptic drug (AED) and mood stabiliser sodium valproate (also known as valproate, VPA) has been evidenced by previous research; however, these findings have often been limited by a small population sample of exposed women and a retrospective study design. Many factors contribute to the teratogenicity of VPA. These include the number of drugs that are co-administered, drug dosage, differences in maternal and/or infant metabolism, the gestational age of the fetus at exposure, and hereditary susceptibility. VPA has been associated with a variety of major and minor malformations, including a 20-fold increase in neural tube defects, cleft lip and palate, cardiovascular abnormalities, genitourinary defects, developmental delay, endocrinological disorders, limb defects, and autism. It has been suggested that polytherapy treatment in epileptic pregnant women increases the risk of teratogenicity in offspring. Furthermore, there is an established relationship between VPA dose and adverse outcome. Large single doses of VPA potentially cause high peak levels in the fetal serum resulting in deleterious effects. Currently there is an increase in the number of national and international pregnancy registries being formed in an effort to better identify the teratogenic effects of AEDs. These efforts hope to enhance our understanding of AEDs and their associated risks by addressing past study limitations.

Hiperhomocisteinemia en pacientes tratados con antiepilépticos. Efecto de diferentes dosis de ácido fólico

BACKGROUND AND OBJECTIVE

An increase homocysteine values, which is an independent risk factor for atherotrombotic disease, can be produced with antiepileptic treatment. The aims of this study were: 1) to assess the frequency and determinant factors of hyperhomocysteinemia in adult patients receiving antiepileptic drugs, and 2) to know the effect of different doses of folic acid.

PATIENTS AND METHOD

Ninety eight patients and 100 healthy controls similar in age and gender were studied. Eighty six patients were treated with hepatic enzyme inductors (diphenylhydantoine and/or phenobarbital and/or primidone and/or carbamazepine), 5 received non inductors (valproate) and 7 were treated with both in combination. Thirty eight patients were randomized to receive in an open and concurrent way folic acid, 0.2 mg (n = 18) or 5.2 mg (n = 20) daily for 3 months.

RESULTS

Homocysteine values were increased in patients in relation with controls (mean [SD]12.2 [6.7] 95% confidence interval [CI],10.0-13.5 vs 8.8[2.2] 95% CI, 8.3-9.2 micromol/l; p < 0.001). Hyperhomocysteinemia was found in 28 patients and 4 controls (28.6% vs 4.0%; p < 0.001). In a multivariate analysis hyperhomocysteinemia was positively associated with treatment with antiepileptic inductors and negatively with folate values and female gender. Homocysteine values decreased after treatment with folic acid at high and low doses (p < 0.001 for both groups), and the values observed in the latter group were similar to those in healthy controls.

CONCLUSIONS

Hyperhomocysteinemia is frequent in patients treated with antiepileptic drugs. Treatment with hepatic enzyme inductors and low folate values are predictors of hyperhomocysteinemia. Administration of folic acid, even at very low doses, produces a significant decrease of homocysteinemia in these patients.

Pharmacorefractory status epilepticus due to low vitamin B6 levels during pregnancy

We report a patient with pyridoxine-dependent epileptic seizures during early childhood. She had been completely seizure free for 23 years until she became pregnant. During the week 14 of her pregnancy, status epilepticus developed and was refractory to antiepileptic drugs but responded to intravenous administration of vitamin B6. Vitamin B6 levels were found to be decreased during pregnancy, although the patient reported continued and regular oral supplementation. Possible reasons for decreased vitamin B6 levels leading to status epilepticus are discussed.

Antiepileptic drugs as independent predictors of plasma total homocysteine levels

Low folate levels have consistently been reported in patients with epilepsy on phenytoin (PHT), phenobarbital (PB) and primidone (PRD), while data on valproate (VPA) are conflicting. Furthermore, antiepileptic drugs (AEDs) may be associated with high levels of plasma total homocysteine (p-tHcy). Therefore, we have investigated the levels of p-tHcy, serum folate (S-FA) and erythrocyte folate (E-FA) in patients on PHT, PB and PRD (Group 1, n=21) and VPA (Group 2, n=24). Both groups had their own matched controls. Blood samples were drawn fasting and 6 h post methionine loading (6 h-PML). The Group 1 patients had fasting and 6 h-PML p-tHcy levels significantly higher than their controls (P=0.05 and <0.0001, respectively), and patients without dietary multivitamin supplementation (n=14), had lower fasting S-FA and E-FA levels than their controls (P=0.02 and 0.0003, respectively). The Group 2 patients had fasting and 6 h-PML levels of p-tHcy, S-FA and E-FA not different from their controls. In a multiple stepwise regression model comprising all subjects (n=90), the AEDs of Group 1 and the S-FA levels were independent predictors of p-tHcy levels. Thus, PHT, PB and PRD are associated with high p-tHcy and low folate levels, whereas VPA does not influence S-FA, E-FA and p-tHcy levels in adult patients.

Folate, homocysteine and methionine loading in patients on carbamazepine

OBJECTIVES

Some antiepileptic drugs (AEDs) are associated with low levels of serum (S-FA) and erythrocyte folate (E-FA) and high levels of plasma total homocysteine (p-tHcy). We have explored the concentrations of S-FA, E-FA and p-tHcy in patients on carbamazepine (CBZ). The methionine loading test was applied for better assessment of mildly impaired homocysteine metabolism.

MATERIAL AND METHODS

The study comprised 42 adult patients on CBZ and 42 matched healthy controls. Blood samples were drawn prior to and 6 h post methionine loading (6 h-PML) (0.1 g/kg body weight).

RESULTS

The patients on CBZ had significantly lower concentrations of fasting S-FA and E-FA than the controls (P=0.0004, P=0.003, respectively). Fasting and 6 h-PML p-tHcy concentrations were significantly higher in the patients than in the controls (P=0.03 and P=0.0001, respectively). The methionine loading test identified additional patients with hyperhomocysteinemia undetected by fasting p-tHcy.

CONCLUSION

CBZ therapy may be associated with low folate and high p-tHcy levels.