Evidence that folic acid deficiency is a major determinant of hyperhomocysteinemia in Parkinson's disease

In the present work we measured blood levels of total homocysteine ((t)Hcy), vitamin B(12) and folic acid in patients with Parkinson s disease (PD) and in age-matched controls and searched for possible associations between these levels with smoking, alcohol consumption, L-DOPA treatment and disease duration in PD patients. We initially observed that plasma (t)Hcy levels were increased by around 30 % in patients affected by PD compared to controls. Linear correlation, multiple regression and comparative analyses revealed that the major determinant of the increased plasma concentrations of (t)Hcy in PD patients was folic acid deficiency, whereas in controls (t)Hcy levels were mainly determined by plasma vitamin B(12) concentrations. We also observed that alcohol consumption, gender and L-DOPA treatment did not significantly alter plasma (t)Hcy, folic acid and vitamin B(12) levels in parkinsonians. Furthermore, disease duration was positively associated with (t)Hcy levels and smoking was linked with a deficit of folic acid in PD patients. Considering the potential synergistic deleterious effects of Hcy increase and folate deficiency on the central nervous system, we postulate that folic acid should be supplemented to patients affected by PD in order to normalize blood Hcy and folate levels, therefore potentially avoiding these risk factors for neurologic deterioration in this disorder.

Serum vitamin B12 levels in the aged

In an attempt to throw light on the question of age-related variations in the normal blood content of cobalamin and on the frequency of deficiencies of antimegaloblastic nutriments in the elderly, 273 geriatric patients have been investigated. Low serum vitamin B12 values were found in one third of these patients, due to latent pernicious anaemia in five and malabsorption in seven cases, and probably caused by nutritional deficiency of folate or cobalamin in 78 cases. In that part of the series with apparently normal vitamin B12 levels, the mean value (379+/-14 pg/ml) was lower than the mean (456+/-20 pg/ml) for a younger control group. However, this cannot be taken as a sign of a physiological lowering of the cobalamin values with age, as nutritional deficiencies could not be ruled out in this part of the series. It is concluded that serum vitamin B12 assays should be performed rather liberally in the aged. Patients with nutritional deficiency of cobalamin or folate should be treated, even if frank megaloblastic anaemia is not present.

Quantification of key red blood cell folates from subjects with defined MTHFR 677C>T genotypes using stable isotope dilution liquid chromatography/mass spectrometry

Red blood cell (RBC) folate levels are established at the time of erythropoiesis and therefore provide a surrogate biomarker for the average folate status of an individual over the preceding four months. Folates are present as folylpolyglutamates, highly polar molecules that cannot be secreted from the RBCs, and must be converted into their monoglutamate forms prior to analysis. This was accomplished using an individual's plasma pteroylpolyglutamate hydrolase by lysing the RBCs in whole blood at pH 5 in the presence of ascorbic acid. Quantitative conversion of formylated tetrahydrofolate derivatives into the stable 5,10-methenyltetrahydrofolate (5,10-MTHF) form was conducted at pH 1.5 in the presence of [(13)C(5)]-5-formyltetrahydrofolate. The resulting [(13)C(5)]-5,10-MTHF was then used as an internal standard for the formylated forms of tetrahydrofolate that had been converted into 5,10-MTHF as well any 5,10-MTHF that had been present in the original sample. A stable isotope dilution liquid chromatography-multiple reaction monitoring/mass spectrometry method was validated and then used for the accurate and precise quantification of RBC folic acid, 5-methyltetrahydrofolate (5-MTHF), tetrahydrofolate (THF), and 5,10-MTHF. The method was sensitive and robust and was used to assess the relationship between different methylenetetrahydrofolate reductase (MTHFR) 677C>T genotypes and RBC folate phenotypes. Four distinct RBC folate phenotypes could be identified. These were classified according to the relative amounts of individual RBC folates as type I (5-MTHF >95%; THF <5%; 5,10-MTHF <5%), type II (5-MTHF <95%; THF 5% to 20%; 5,10-MTHF <5%), type III (5-MTHF >55%; THF >20%; 5,10-MTHF >5%), and type IV (5-MTHF <55%; THF >20%; 5,10-MTHF >5%).

High rate of maternal vitamin B12 deficiency nearly a decade after Canadian folic acid flour fortification

Vitamin B12 deficiency may be an independent risk factor for neural tube defects (NTD). We determined the prevalence of biochemical B12 deficiency (<125 pmol/l) among 10 622 Ontarian women aged 15-46 years who underwent concomitant testing of serum bhCG and B12 9 years after the implementation of Canadian folic acid flour fortification. The overall prevalence of biochemical B12 deficiency was 7.4%. Relative to non-pregnant women, the adjusted odds ratio (95% confidence interval) of biochemical B12 deficiency was 0.78 (0.60-1.0) among women pregnant 28 days gestation or less and was 1.4 (1.1-1.8) after 28 days gestation. About 1 in 20 women may be deficient in B12 in early pregnancy. The impact on maternal and fetal well-being, including preventable NTD, should be considered.

Blood folate levels: the latest NHANES results

Data from the National Health and Nutrition Examination Surveys. Very large increases in blood folate levels of the U.S. population occurred between 1988-1994 and 1999-2000. Small fluctuations in blood folate levels occurred over the time period 1999-2006. The median red blood cell (RBC) folate level of the U.S. population 4 years of age and older was 266 ng/mL in 2005-2006. The median serum folate level of the U.S. population 4 years of age and older was 12.2 ng/mL in 2005-2006. In 2005-2006, the prevalence of low RBC folate (less than 140 ng/mL) among U.S. women of childbearing age (15-45 years) was 4.5%. In 2005-2006, the prevalence of low serum folate (less than 3 ng/mL) among U.S. women of childbearing age was 0.5%. Folate is an essential vitamin for good health. Women of childbearing age are among the population subgroups that have been shown previously to have low blood folate levels. Low blood folate levels are associated with an increased risk of neural tube birth defects. Beginning in 1998, the Food and Drug Administration (FDA) required the addition of folic acid (a form of folate) to all enriched breads, cereals, flours, corn meal, pasta products, rice, and other cereal grain products sold in the United States. Blood folate data from the National Health and Nutrition Examination Surveys (NHANES) have documented improvements in the folate status of the U.S. population after folate fortification was implemented. Red blood cell (RBC) folate measures long-term folate intake and low levels are associated with adverse health effects. Serum folate reflects recent folate intake and low levels are an early indicator of inadequate folate status. Pre- and postfortification blood folate levels of the U.S. population 4 years of age and older and prevalence of low blood folate among women of childbearing age (15-45 years) are reported.

[Measurement of methylmalonic acid, homocysteine and methionine in cobalamin and folate deficiencies and homocysteinuria]

BACKGROUND

Deficiencies of cobalamin (vitamin B12) or folate are common conditions that predispose for anemia and chronic diseases. An elevated concentration of methylmalonic acid in plasma/serum is an indicator of cobalamin deficiency, whereas an increased concentration of total homocysteine in plasma occurs with deficiency of both cobalamin and folate. The biomarkers methylmalonic acid and homocysteine are therefore complementary, and the combination is often requested when conventional tests fail to provide an unambiguous diagnosis.

MATERIAL AND METHODS

This article summarizes publications, retrieved through Medline, describing novel strategies for laboratory diagnostics of cobalamin and folate deficiencies.

RESULTS AND INTERPRETATION

Adverse health effects of food fortification and uncritical supplementation with folic acid are explanations for a renewed interest in individual diagnosis of B-vitamin deficiency. Interpretation of methylmalonic acid and homocysteine test results requires knowledge of kidney function, as renal failure causes an increase in the concentrations of both metabolites. Homocystinuria is a condition that also causes increased levels of plasma homocysteine. This condition is an inborn error with a higher prevalence (1 : 6400) than previously recognized; which usually responds favourably to homocysteine-lowering therapy. Patients with homocysteinuria have high levels of methionine in plasma and knowledge of plasma methionine concentration may therefore distinguish these patients from those with conditions like B-vitamin deficiencies or renal failure, which are accompanied by normal or low to normal methionine concentrations. Complementarity, logistics, small sample volumes and costs therefore favour a combined analysis of methylmalonic acid, homocysteine and methionine in a single sample. Such an approach also allows assessment of cobalamin status in small volume capillary blood samples drawn from newborns and infants.

Abnormal folate metabolism as a risk factor for first-trimester spontaneous abortion

OBJECTIVE

To assess the potential role of folic acid in early pregnancy loss by measuring homocysteine (hcy) levels in healthy, pregnant women who present with a current first-trimester miscarriage.

STUDY DESIGN

This was a cross-sectional analysis comprising 13 patients aged 18-31 years old who had a scheduled dilatation and curettage for a first-trimester miscarriage. The controls were 15 patients of similar maternal age presenting for a first-trimester prenatal care visit. Following completion of a 21-item, structured questionnaire, patients were excluded from the study if they had any known risk factors for a first-trimester miscarriage. The remaining patients provided blood samples for measurement of homocysteine and red blood cell folate. Cases and controls were compared using a standard 2-sample t test. In order to detect a clinically relevant 2.3 micromol/L difference in homocysteine levels, 11 cases and 8 controls were needed.

RESULTS

The mean hcy level in cases (5.8 umolmol/L) vs. controls (5.7 micromol/L) was not significantly different (p = 0.83), and all individual values fell within the normal range expected in pregnant women. Red blood cell folate levels (cases=586 ng/mL, controls=611 ng/mL) were also not significantly different (p = 0.72), and no cases of folate deficiency were detected. Maternal age (cases=26, controls=25) and gestational age (cases = 8.8 weeks, controls = 8.4 weeks) were similar between the 2 groups.

CONCLUSION

In this community-based pilot study, abnormal folate metabolism was not an apparent risk factor for spontaneous first-trimester pregnancy loss.

A randomised double-blind placebo-controlled trial of folic acid supplementation of cholinesterase inhibitors in Alzheimer's disease

OBJECTIVES

(1) to assess the effect of 1 mg folic acid supplementation of cholinesterase inhibitors (ChI) in a 6 month double-blind placebo-controlled study of patients with Alzheimer's Disease (AD) and (2) to assess whether outcome measures were affected by changes in homocysteine levels.

METHOD

Fifty-seven consecutive outpatients with probable AD were treated concurrently with a ChI and either folic acid or placebo. None had conditions or medication known to interfere with folate metabolism. Fasting folate and homocysteine levels were measured prior to commencing ChI and 6 months later. Response was categorised using criteria of the National Institute of Clinical Excellence (NICE).

RESULTS

Twelve males and 29 females completed treatment (mean age 76.27 SD 6.23 years, Mini-Mental State Examination (MMSE) 23.49 SD 3.53, baseline homocysteine 18.39 SD 4.62 micromoles per litre). 23 received folic acid and 18 placebo. There were no significant baseline differences or use of individual ChI between the two arms. After 6 months a significant difference was seen in the change from baseline in combined Instrumental Activities of Daily Living and Social Behaviour scores between arms (folate+1.50 (SD 5.32) vs placebo -2.29 (SD 6.16) (p=0.03) but not change in MMSE scores. Sixteen of 23 subjects receiving folic acid and 7/18 placebo subjects were classified as NICE responders (p=0.05).

CONCLUSION

This pilot double blind study suggests that response to ChI in patients with AD may be improved by the use of folic acid. The relationship between any change in homocysteine levels and response to treatment is discussed.

Folate status and mood: is there a relationship?

Objective

To explore the relationship between subjective mood, folate status and homocysteine in healthy individuals.

Design

Subjective mood assessments were completed twice daily over the course of one week using the Positive and Negative Affect Scale (PANAS). The PANAS is a validated scale which considers mood state on two distinct continua, one reflecting positive mood and the other negative mood, each requiring response to 10 adjectives on a Likert scale. A blood sample was taken on one occasion at the start of the week during which subjective mood was assessed and analysed for red-blood-cell (RBC) folate, serum folate and plasma homocysteine concentrations.

Subjects

Male volunteers aged 19–47 years (n= 58) were recruited from local industries.

Results

High concentrations of RBC folate were associated with less variability (lower standard deviation) in negative mood (P= 0.023). Subjective mood, however, was not related to serum folate or homocysteine.

Conclusions

This study appears to be the first to uncover an association between long-term folate status and subjective mood (employing the PANAS) in healthy males. More research is needed to further explore the relationship between nutritional status and mood.

B Vitamin Plasma Levels and the Risk of Ischemic Stroke and Transient Ischemic Attack in a German Cohort

Background and Purpose— Data from prospective studies on the associations between B vitamin plasma levels and the risk of stroke are limited. We investigated the individual and combined effects of plasma folate, vitamin B12, and pyridoxal 5-phophate (PLP) levels on the risk of ischemic stroke and transient ischemic attack (TIA) in a large, prospective German cohort.

Methods— Incident cases of ischemic stroke or TIA were identified among 25 770 participants (age 35 to 65 years) of the European Prospective Investigation into Cancer and Nutrition-Potsdam Study during 6.0±1.5 years of follow-up. The present analysis is based on a case-cohort study comprising 779 subjects free from cardiovascular disease and 188 incident cases of cerebral ischemia (ischemic stroke or TIA). Multivariable Cox proportional-hazard models were applied to evaluate the association between B vitamin levels and risk of cerebral ischemia.

Results— Participants in the lowest tertile of vitamin B12 values were at increased risk of cerebral ischemia compared with subjects in the highest tertile; this was not observed, however, for either folate or PLP. In subgroup analyses, the relative risks were similar in magnitude for stroke and TIA. When various combinations of B vitamin tertile levels were analyzed, only combined low folate and vitamin B12 levels (relative risk, 2.24; 95% CI, 1.10 to 4.54) were significantly related to an increased risk of cerebrovascular ischemia.

Conclusions— Our data suggest that low vitamin B12 plasma levels, particularly in combination with low folate levels, increase the risk of cerebral ischemia. This effect may be mediated at least partly through elevations of homocysteine levels.

Elevated plasma homocysteine concentration in elderly patients with mental illness is mainly related to the presence of vascular disease and not the diagnosis

BACKGROUND

Plasma total homocysteine (tHcy) is often elevated in patients with mental illness. Since patients with mental illness and vascular disease exhibit a higher plasma tHcy concentration than patients without vascular disease, it is possible that elevated plasma tHcy in mental illness is mainly due to concomitant vascular disease.

METHODS

We have investigated plasma tHcy, cobalamin/folate status, renal function and the presence of vascular disease in patients with vascular dementia (VaD, n = 501), Alzheimer's disease (AD, n = 300), depression (n = 259) and in healthy subjects (n = 144) stratified according to age (below and above 75 years).

RESULTS

Plasma tHcy concentration showed the highest increase in patients with VaD compared to patients with AD or depression. After the exclusion of patients with cobalamin/folate deficiencies and increased serum creatinine, patients with AD or depression above 75 years with vascular disease showed a similar elevation of plasma tHcy concentration as patients with VaD. Furthermore, patients with AD and depression without vascular disease showed a similar plasma tHcy concentration to healthy subjects.

CONCLUSION

The findings imply that elevated plasma tHcy concentration in elderly patients with mental illness is mainly associated with the presence of vascular disease and is not related to the specific psychogeriatric diagnosis.

Correlations between folate, B12, homocysteine levels, and radiological markers of neuropathology in elderly post-stroke patients

OBJECTIVE

To investigate serum levels of folate, B12, and total homocysteine (tHcy) in elderly post-stroke patients, and the possible correlations with radiological markers of neuropathology.

DESIGN

Cross-sectional study.

SETTING

Department of Neurology, Cardinal Tien Hospital.

SUBJECTS

Eighty-nine elderly post-stroke patients were enrolled for dietary assessment and blood tests. Neuroradiological assessment was done in 62 of these patients.

MAIN OUTCOME MEASURES

Dietary folate and vitamin B12 intakes were evaluated by a 24-h recall system using a semi-quantitative questionnaire. Circulating levels of folate, B12, and tHcy were measured. Magnetic resonance imaging (MRI) or computed tomography (CT) was used for evaluation of brain lesions including infarction and atrophy.

RESULTS

Mean folate and B12 intakes of these post-stroke patients were 69% and 261% of the recommended dietary allowances (RDA), respectively. Inadequate folate levels, defined as serum folate < 6 ng/mL, was noted in 68% of these patients. Hyperhomocysteinemia levels (tHcy >or=15 micromol/L) were observed in 48%. According to tertiles of serum tHcy and folate levels, the rate of brain atrophy, but not brain infarctions, are significantly associated with elevated tHcy (P = 0.0126) and decreased folate levels (P = 0.0273). After adjustments for age, sex, disease status, brain infarctions and carotid stenosis, the odds ratio of brain atrophy was 9.8 (95% CI: 1.7-56.4, P = 0.0101) in the hyperhomocysteinemia group and 9.6 (95% CI: 1.1-81.3, P = 0.0377) in the low folate group (serum folate < 3.0 ng/mL) compared with the group with normal tHcy and folate levels. No significant association was noted between vitamin B12 levels and brain lesions.

CONCLUSIONS

Our data shows that folate deficiency and hyperhomocysteinemia are prevalent in elderly post-stroke patients. These two conditions are strongly and independently associated with the development of brain atrophy.

Gender-specific modulation of tumorigenesis by folic acid supply in the Apc mouse during early neonatal life

Epidemiological studies suggest an inverse association between folic acid intake and colorectal cancer risk. Conversely, conventional treatment of existing tumours includes the use of folate antagonists. This suggests that the level of exposure to folate and its timing in relation to stage of tumorigenesis may be critical in determining outcomes. We hypothesised that folic acid depletion in utero and during early neonatal life may affect tumorigenesis in offspring. To investigate this hypothesis, female C57Bl6/J mice were randomised to a folic acid adequate (2 mg folic acid/kg diet) or folic acid depleted diet (0.4 mg folic acid/kg) from mating with Apc+/Min sires and throughout pregnancy and lactation. At weaning the Apc+/Min offspring were randomised to a folic acid adequate (2 mg folic acid/kg diet) or depleted (0.26 mg folic acid/kg diet) diet, creating four in utero/post-weaning dietary regimens. At 10 weeks post-weaning, mice were killed and the intestinal tumour number and size were recorded. Folic acid depletion during pregnancy and post-weaning reduced erythrocyte folate concentrations in offspring significantly. Folic acid depletion during pregnancy and lactation did not affect tumour multiplicity or size. However, female mice fed normal folic acid diets post-weaning had more, and larger, tumours when compared with depleted females and both depleted and adequate folic acid fed males. These data suggest that folate depletion post-weaning was protective against neoplasia in female Apc+/Min mice and highlights the need for further investigation of the optimal timing and dose of folic acid supplementation with regard to colorectal cancer risk.

Are heterocygotes for classical homocystinuria at risk of vitamin B12 and folic acid deficiency?

OBJECTIVES/DESIGN

Comparative cross-sectional study to assess homocysteine and vitamin status in carriers of CBS gene mutations.

METHOD

Subjects included 34 parents (13 males, 21 females, age 27-59 years) of 30 patients with classical homocystinuria due to homozygous cystathionine beta-synthase deficiency. Control subjects were matched for gender and age (13 males, 21 females, age 25-59 years). All subjects were of Qatari origin, had normal liver and renal function tests and had not taken drugs or vitamin supplements prior to the study. The concentrations of homocysteine, folic acid and vitamins B6 and B12 in blood were determined after an overnight fast.

RESULTS

Heterozygous carriers had significantly increased fasting levels of homocysteine compared to controls (9.1 vs. 8.1 micromol/l, P=0.012). Both folic acid (328 vs. 478 pmol/l, P=0.002) and vitamin B12 concentrations (232 vs. 287 pmol/l, P=0.013) were reduced whilst there was no significant difference in vitamin B6 levels between the two groups (5.8 vs. 6.44 microg/l).

CONCLUSIONS

Increased homocysteine concentrations in CBS gene mutation carriers are associated with reduced concentrations of folic acid and vitamin B12 in blood. In view of the adverse effects of mild hyperhomocysteinemia, routine testing of vitamin status in parents of homocystinuria patients may be warranted. The causal relationship and pathophysiological consequences are uncertain; it is likely that CBS gene mutation carriers need higher doses of dietary vitamins.

Trends in blood folate and vitamin B-12 concentrations in the United States, 1988 2004

BACKGROUND

Monitoring the folate status of US population groups over time has been a public health priority for the past 2 decades, and the focus has been enhanced since the implementation of a folic acid fortification program in the mid-1990s.

OBJECTIVE

We aimed to determine how population concentrations of serum and red blood cell (RBC) folate and serum vitamin B-12 have changed over the past 2 decades.

DESIGN

Measurement of blood indicators of folate and vitamin B-12 status was conducted in approximately 23,000 participants in the prefortification third National Health and Nutrition Examination Survey (NHANES III; 1988-1994) and in approximately 8000 participants in 3 postfortification NHANES periods (together covering 1999-2004).

RESULTS

Serum and RBC folate concentrations increased substantially (by 119-161% and 44-64%, respectively) in each age group in the first postfortification survey period and then declined slightly (by 5-13% and 6-9%, respectively) in most age groups between the first and third postfortification survey periods. Serum vitamin B-12 concentrations did not change appreciably. Prevalence estimates of low serum and RBC folate concentrations declined in women of childbearing age from before to after fortification (from 21% to <1% and from 38% to 5%, respectively) but remained unchanged thereafter. Prevalence estimates of high serum folate concentrations increased in children and older persons from before to after fortification (from 5% to 42% and from 7% to 38%, respectively) but decreased later after fortification.

CONCLUSIONS

The decrease in folate concentrations observed longer after fortification is small compared with the increase soon after the introduction of fortification. The decrease is not at the low end of concentrations and therefore does not raise concerns about inadequate status.

Comparison of blood folate levels among pregnant Chinese women in areas with high and low prevalence of neural tube defects

Objective

To characterise plasma and red-blood-cell (RBC) folate status among pregnant women in an area with an extremely high prevalence of neural tube defects, and to compare them with those of women from a low prevalence area.

Design

A cross-sectional survey conducted in 2003.

Setting

One county and one city from each of the high prevalence area and the low prevalence area in China.

Subjects

Five hundred and sixty-two women in their first trimester of pregnancy in the high prevalence area and 695 pregnant women in the low prevalence area.

Results

Women in the high prevalence area had less than half the plasma and RBC folate concentrations (12.2 and 440.0 nmol l− 1, respectively) of women in the low prevalence area (33.5 and 910.4 nmol l− 1, respectively). In the high prevalence area, 40% of rural women were deficient in RBC folate and 50% were deficient in plasma folate; 20% of urban women were deficient in RBC folate and 30% deficient in plasma folate. In contrast, only 4% (RBC folate) and 6% (plasma folate) of rural women, and 2% (RBC folate) and 1% (plasma folate) of urban women, were folate-deficient in the low prevalence area. Less than 10% of rural and about 26% of urban women in the high prevalence area took folic acid periconceptionally, compared with 70% and 60% of women in the low prevalence area.

Conclusions

Blood folate deficiency is highly prevalent among pregnant women in an area of China with a very high prevalence of neural tube defects.

[Study on the correlation of serum folate and red blood cell folate level with birth defects and unexplained recurrent pregnancy loss]

OBJECTIVE

To understand the correlation of lower serum folate, and red blood cell (RBC) folate level with birth defects including unexplained recurrent pregnancy loss, and to evaluate the role of RBC folate level as a suitable marker for folate supplement.

METHODS

Two hundred and ninety-nine non-pregnant women at child-bearing age with a birth defect history were selected as birth defect group. The levels of serum and RBC folate, and serum vitamin B(12) were determined. By comparing with the group of non-pregnant women at child-bearing age without any birth defect history (control group), we evaluated the correlation between lower serum folate, RBC folate level and main kinds of birth defects including unexplained recurrent pregnancy loss. And the levels of serum and RBC folate of birth defect group were also determined and compared before and after oral folate intake (5 mg/d) for one month.

RESULTS

The serum folate level of birth defect group was not different from the control group (17 - 26 vs 14 nmol/L, P > 0.05). The RBC folate level of birth defect group except the urinary defect was significantly lower compared with the control group (233 - 547 vs 689 nmol/L, P < 0.05). After the oral folate intake (5 mg/d), the serum folate level of unexplained recurrent pregnancy loss group and neural tube defects group were significantly increased than before [(22 +/- 9) vs (27 +/- 12) nmol/L, (19 +/- 10) vs (25 +/- 18) nmol/L; P < 0.05]. The RBC folate level of unexplained recurrent pregnancy loss group and congenital heart defect group were significantly increased than before [(374 +/- 275) vs (567 +/- 397) nmol/L, (322 +/- 205) vs (527 +/- 351) nmol/L, P < 0.05].

CONCLUSION

RBC folate level is more closely correlated than serum folate level with the incidence of main birth defect.

Influence of high homocysteine and low folate plasmatic levels in medium-term prognosis after acute coronary syndromes

BACKGROUND

To test prospectively whether moderate hyperhomocysteinemia and low folate levels could have an influence in the prognosis of 155 patients who presented with an acute coronary syndrome.

METHODS AND RESULTS

After a mean follow-up of 13.4+/-7.4 months, patients with low folate levels had higher percentages of cardiovascular death and major cardiovascular events (33% vs. 5%, p<0.001; 44% vs. 22%, p<0.05) and patients with high homocysteine levels had a higher percentage of major cardiovascular events (31% vs. 14.5%, p<0.03). Kaplan-Meier survival estimates analysis showed that patients with low folate levels had a significantly higher probability of cardiovascular death and lower free-of-events survival (log rank statistic: 21.17, p<0.001 and 6.59, p=0.01). Patients with high homocysteine levels had a lower free-of-events survival (log rank statistic: 4.95, p=0.02). Different survival multivariate analysis model showed that the presence of low folate levels was an independent predictor of cardiovascular death (hazard ratio 8.85, 95% confidence interval 2.6-29.3, p<0.000) and high homocysteine levels was identified as independent predictor of major cardiovascular events (hazard ratio 2.34, 95% confidence interval 1.07-5.12, p<0.03).

CONCLUSIONS

Low folate levels and moderate hyperhomocysteinemia were identified as independent predictors of cardiovascular events in the follow-up.