Influence of maternal vitamin B12 and folate on growth and insulin resistance in the offspring

The burden of chronic noncommunicable diseases (NCDs) such as diabetes, obesity and cardiovascular disease is shifting rapidly to low- and middle-income countries. It calls for a review of the classic 'dogma' of genetic predisposition, precipitated by adult lifestyle. The paradigm of early life origins of chronic disease has focused attention on maternal health and nutrition as major determinants of the health of the offspring. India has high burden of maternal ill health and also of diabetes and cardiovascular disease, offering unique opportunities to study the links between the two. Pune studies showed that the Indian babies were thin but fat (more adipose) compared to European babies, and that maternal micronutrient status during pregnancy was a determinant of offspring size and body composition. Two thirds of the mothers had low vitamin B12 concentrations, while folate deficiency was rare. Higher circulating concentrations of homocysteine predicted smaller baby size. Follow-up studies revealed that higher maternal folate in pregnancy predicted higher adiposity and insulin resistance in the child at 6 years of age, and that low maternal vitamin B12 exaggerated the risk of insulin resistance. Low maternal vitamin B12 status is also associated with increased risk of neural tube defects and poor offspring cognitive functions. Our results suggest an important role for maternal one-carbon metabolism in offspring growth and programming of NCD risk. These ideas are supported by animal studies. Improvement of adolescent nutrition could effect intergenerational prevention of chronic diseases.

Low clinical utility of folate determinations in primary care setting

BACKGROUND

Fortification of cereal products with folic acid is not mandatory in Israel, yet folate deficiency remains rare and is usually associated with poor diet, malabsorption, alcoholism, or use of certain drugs. A retrospective review of all folate level determinations performed between January 2004 and January 2007 in the central district of Clalit Health Services in Israel revealed that only 4.3% of the 43,176 tests ordered were below the norm (5.6 nmol/L).

OBJECTIVES

To determine parameters that identify folate-deficient patients without known risk factors and to establish principles that aid the physician in deciding when to order folate determinations.

METHODS

Study population included 152 patients from 13 large primary care clinics with folate deficiency but without known risk factors for folate deficiency (37 with anemia). They were matched with 556 controls (141 with anemia).The medical records were reviewed for the indication of the test and treatment that followed the results.

RESULTS

Hematologic indices, vitamin B12, ferritin, and transferrin saturation levels were similar in the study and control groups. Subgroup comparisons based on anemia status showed similar results. The clinical indications for folate determinations were similar in the folate-deficient patients and the control group. Only 68 of 152 patients (44.7%) were prescribed a folate supplement.

CONCLUSIONS

Neither laboratory parameters nor clinical findings in patients' charts were capable of distinguishing folate-deficient patients from controls. It seems that folate determinations in patients without known risk factors for folate deficiency are of little clinical significance.

Utility, charge, and cost of inpatient and emergency department serum folate testing

BACKGROUND

Serum folate levels are commonly ordered for multiple indications in the inpatient and emergency department settings. Since mandatory folic acid fortification in 1998, there has been a decreasing prevalence of folate deficiency in the United States.

OBJECTIVE

Our objective was to determine the indications, rate of deficiency, charge and cost per deficient result, and change in management per deficient result in serum folate testing in inpatients and emergency department patients.

DESIGN

Retrospective analysis of all inpatient and emergency department serum folate tests.

METHODS

We analyzed all inpatient and emergency department serum folate tests performed over a 12-month period. We reviewed the charts of 250 patients and all low-normal or deficient serum folate levels to determine indications, comorbidities, and change in management based on result. Charge and cost analyses were performed.

SETTING/PATIENTS

All inpatient and emergency department patients with a serum folate test performed at a major medical center in Boston, Massachusetts.

RESULTS

A total of 2093 serum folate tests were performed in 1944 patients with 2 deficient levels. The most common indications were anemia without macrocytosis and anemia with macrocytosis. The amount charged per deficient result was $158,022. The cost to the hospital per deficient result was less than $2093.

CONCLUSIONS

In folic acid fortified countries, serum folate testing has low utility and poor cost effectiveness for all indications in inpatients and emergency department patients.

Prospective study of genomic hypomethylation of leukocyte DNA and colorectal cancer risk

BACKGROUND

Systematic genome-wide reductions of methylated cytosine (5-mC) levels have been observed in colorectal cancer tissue and are suspected to play a role in carcinogenesis, possibly as a consequence of inadequate folate intake. Reduced 5-mC levels in peripheral blood leukocytes have been associated with increased risk of colorectal cancer and adenoma in cross-sectional studies.

METHODS

To minimize disease- and/or treatment-related effects, we studied leukocyte 5-mC levels in prospectively collected blood specimens of 370 cases and 493 controls who were cancer-free at blood collection from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Leukocyte 5-mC level was determined by a high-pressure liquid chromatography (HPLC)/tandem mass spectrometry method and expressed as the relative amount of methyl to total cytosine residues, or %5-mC. We estimated the association between colorectal cancer risk and %5-mC categories by computing ORs and 95% confidence intervals (CI) through logistic regression modeling.

RESULTS

We observed no dose-dependent association between colorectal cancer and%5-mC categories (lowest vs. highest tertile: OR, 1.14; 95% CI, 0.80-1.63; P(trend) = 0.51). However, among subjects whose 5-mC levels were at the highest tertile, we observed an inverse association between natural folate intake and colorectal cancer (highest tertile of natural folate vs. lowest: OR, 0.35; 95% CI, 0.17-0.71; P(trend) = 0.003; P(interaction) = 0.003).

CONCLUSIONS

This prospective investigation show no clear association between leukocyte 5-mC level and subsequent colorectal cancer risk but a suggestive risk modification between 5-mC level and natural folate intake.

IMPACT

Adequate folate status may protect against colorectal carcinogenesis through mechanisms involving adequate DNA methylation in the genome.

No increased mortality risk in older persons with unexplained anaemia

BACKGROUND

in older persons, anaemia is associated with a number of unfavourable outcomes. In approximately 30% of older persons with anaemia, the cause of the anaemia is unexplained. We assessed the clinical differences between subjects with explained and unexplained anaemia and investigated whether these subjects have different mortality patterns compared with subjects without anaemia.

DESIGN

observational prospective follow-up study.

SETTING

the Leiden 85-plus study.

PARTICIPANTS

four hundred and ninety-one persons aged 86 years.

METHODS

the study population was divided in three groups: (i) no anaemia (reference group, n=377), (ii) explained anaemia (iron deficiency, folate deficiency, vitamin B12 deficiency, signs of myelodysplastic syndrome or renal failure, n=74) and (iii) unexplained anaemia, (n=40). Mortality risks were estimated with Cox-proportional hazard models.

RESULTS

haemoglobin levels were significantly lower in subjects with explained anaemia than in subjects with unexplained anaemia (P<0.01). An increased risk for mortality was observed in subjects with explained anaemia [HR: 1.93 (95% CI: 1.47-2.52), P<0.001], but not in subjects with unexplained anaemia [HR: 1.19 (95% CI: 0.85-1.69), P=0.31]. Adjusted analyses (sex, co-morbidity, MMSE, institutionalised and smoking) did not change the observed associations for both explained and unexplained anaemic subjects.

CONCLUSION

older subjects with unexplained anaemia had similar survival compared with non-anaemic subjects. Increased mortality risks were observed in subjects with explained anaemia compared with non-anaemic subjects.

Healthcare-related characteristics of low vs normal folate levels among women of child-bearing age

OBJECTIVE

Despite the institution of mandatory folic acid fortification in the US, folate deficiencies still occur and are associated with an increased risk of several conditions. Since little is known regarding the relationship between folate status and other clinical, demographic, and healthcare-related characteristics, the objective of the study was to compare healthcare-related characteristics among US child-bearing age women with low vs normal red blood cell (RBC) folate levels.

RESEARCH DESIGN AND METHODS

Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used to conduct a retrospective cohort study. Women (aged 18-45 when surveyed) were categorized in two cohorts for comparison: normal RBC folate level (≥ 140 ng/ml, NFL) and low RBC folate level (<140 ng/ml, LFL).

RESULTS

Of the 2816 subjects, 5.9% were assigned to the LFL cohort and were significantly younger (28 vs 30 years, p=0.01); a greater proportion were 18-25 years old (55.7% vs 39.9%, p<0.001) or African-American (55.1% vs 22.3%, p<0.01). A lower proportion of LFL women were insured (67.3% vs 75.5%, p=0.01) with low rates of private insurance (39.5% vs 53.1%, p<0.01), while Medicaid/SCHIP coverage was similar (16.8% vs 15.1%, p=0.56). Predictors of low folate levels included aged 36-45 years (OR: 2.14 [95% CI: 1.04, 4.39]) and never being married (2.65 [1.34, 5.24]), while a household income ≥ $75,000 reduced the likelihood of having low folate levels (0.20 [0.06, 0.73]).

LIMITATIONS

The proportion of women with low folate levels was small, with the sample size limiting the ability to adjust for other factors during analysis. Medical histories were based on patient interviews and are subject to recall bias.

CONCLUSION

LFL women are younger and have low rates of private insurance coverage compared to women with normal folate levels. Differences in age, marital status, and household income are associated with folate status.

Lack of folate improvement in high risk indigenous Australian adults over an average of 6.5 years: a cohort study

Socioeconomically vulnerable groups in developed countries suffer excess chronic disease due in large part to an energy dense but nutrient poor diet. Low folate can be a marker of poor dietary quality and is also affected by smoking and chronic alcohol intake, all of which cluster in groups with a low socioeconomic position. A 4.5 to 9 year follow-up study of 567 indigenous adults from remote communities in far north Queensland, Australia, from 1998 to 2007 was conducted. Analysis of the effects of demographic factors, smoking, risky alcohol drinking, fruit and vegetable intake and waist circumference on changes in red cell folate (RCF) status was conducted. Prevalence of low red cell folate doubled in the cohort from a high baseline over this seven year period: 36.9% deficient in 2007, 15.9% at baseline (p<0.001). Smoking was associated with lower folate levels. People with a normal RCF were less likely to be smokers, and were more likely to have a greater number of serves of vegetables (RR 1.06, 95% CI 1.02-1.10) than those who were deficient at follow-up. The introduction of voluntary folate fortification since 1995 does not appear to have impacted on the already poor folate status of this cohort of adults. The increased prevalence of low folate has occurred despite improvements in the food supply, indicating the need for nutrition promotion, and subsidies for healthy food in remote communities. The impact of mandatory folate fortification of flour since 2009 should be assessed in this high risk population.

Monitoring folate status in population-based surveys

Folate status assessments depend primarily on the measurement of biomarkers such as serum and red blood cell folate. Lessons learned from a large national monitoring system such as the National Health and Nutrition Examination Survey and a public health intervention such as the implementation of folic acid fortification in the United States have provided useful insights into the challenges of assessing folate status and possible solutions for addressing these challenges. © 2011 International Union of Biochemistry and Molecular Biology, Inc. 2011.

Association between folate status, diabetes, antihypertensive medication and age-related cataracts in elderly Taiwanese

OBJECTIVE

To evaluate possible risk factors for cataract in elderly Taiwanese, and to investigate whether the relationship between age and cataract in older persons is modified by other cataract-associated risk factors.

PARTICIPANTS

A cross-sectional study of 661 males and 645 females aged ≥ 65 yrs was conducted as part of the Elderly Nutrition and Health Survey in Taiwan (1999-2000) (Elderly NAHSIT).

METHODS

Self-reported cataracts were defined as any incidence of cataract that was diagnosed by a physician and treated by anticataractic drugs based on the medical history section of the Elderly NAHSIT. Potential risk factors for cataract were determined by multiple logistic regression analysis of data obtained from the health examination, blood biochemistry and interviewer-administered questionnaires.

RESULTS

Results showed that the prevalence of self-reported cataract increased with age and was significantly higher in older women than in older men. Cataracts were associated with age, diabetes, antihypertensive medication and folate insufficiency in older men, and with age and antihypertensive medication in older women. Folate insufficiency remained associated with cataract in older men who had adequate vitamin B2, B6 and B12 status. Folate insufficiency was associated with cataract after adjustment for other risk factors in older men aged ≥ 75 yrs, while in older men aged 65-74 yrs, only diabetes and antihypertensive medication remained associated with cataract. In addition, age ≥ 75 yrs remained a risk factor for cataract in those without diabetes, not taking hypertensive medication and with normal folate status. Further analysis showed that the strength of the association between age ≥ 75 yrs in older men and cataracts was increased about 1.5-fold when combined with folate insufficiency (interaction p= 0.0198), and increased about 1.8-fold when combined with use of antihypertensive medication (interaction p = 0.0214).

CONCLUSION

Our results suggest that the combination of age ≥ 75 yrs in older men with either folate insufficiency or use of antihypertensive medication had an additive effect on the risk of cataract. Maintenance of good folate status should be emphasized to reduce the risk of cataract in the Taiwanese elderly, especially men.

Trends in folate status in the Taiwanese population aged 19 years and older from the Nutrition and Health Survey in Taiwan 1993-1996 to 2005-2008

To investigate ten year trends in folate status in Taiwanese aged >=19 yrs by three Nutrition and Health Survey in Taiwan (NAHSIT) in 1993-1996, 1999-2000 and 2005-2008. Women had higher blood folate levels than men in all three surveys. The prevalence of folate deficiency (5.2% <3 ng/mL) and insufficiency (34.1% <=6 ng/mL) in men was highest in 2005-2008. Adults aged 19-30 yrs had the lowest blood levels and the highest prevalence of deficiency (8.1% in men; 3.5% in women) and insufficiency (48.6% in men; 25% in women) as compared to other age groups in 2005-2008. Folate insufficiency rate in those aged 31-44 yrs was twice as high in men and three times as high in women in 2005-2008 compared to 1993-1996. In the elderly, folate insufficiency rate (28%) in 2005-2008 was not higher than that of 1993-1996, although it was higher than that found in 1999-2000 (18.4%). Men aged >=80 yrs had the poorest folate status in 2005-2008, and men were twice as likely to have inadequate status as women. Plasma homocysteine (Hcy) levels were higher in older men than older women in both surveys. The elderly had significantly higher plasma tHcy in 2005-2008 compared to the 1999-2000 survey. Dark green vegetables and fruit intake frequency in young adults (19-30 yrs) was the lowest among all age groups. This study suggests that folate status in Taiwan has not improved during the past fifteen years, and has worsened in the young population.

Age-related hearing loss, vitamin B12, and folate in the elderly

OBJECTIVE

Determine the correlation between the hearing threshold and the serum levels of vitamin B12 (cobalamin) and folic acid among elderly subjects (> 60 years) with age-related hearing loss (ARHL).

STUDY DESIGN

Cross-sectional.

SETTING

Community.

SUBJECTS AND METHODS

Subjects included elderly who were found apparently healthy following repeated examination by physicians. The pure tone average (PTA) for the speech and high frequencies, and the serum folate and cobalamin were determined and the correlation found.

RESULTS

The mean ± SD values of serum folate among the subjects with normal PTA in the speech frequencies (0-30 dB) was 412.3 nmol/L ± 17.6 nmol/L, while among those with hearing loss (HL), it was 279.1 nmol/L ± 17.2 nmol/L (P = 0.01). In the high frequencies, the mean ± SD values among the subjects with normal PTA was 426.3 nmol/L ± 17.6 nmol/L, while among those with HL, it was 279.14 nmol/L ± 171.2 nmol/L. The serum cobalamin among the subjects with normal PTA within the speech frequencies was 49.7 pmol/L ± 9.4 pmol/L, while among those with speech-frequency HL, it was 42.6 pmol/L ± 10.2 pmol/L. However, for high frequencies, the mean ± SD values among the subjects with normal PTA was 47.4 pmol/L ± 7.3 pmol/L, while among those with HL, it was 41.3 pmol/L ± 9.2 pmol/L. Spearman's correlation revealed that low folate (correlation coefficient = -0.27, P = 0.01) and cyanocobalamin (correlation coefficient = -0.35, P = 0.02) were significantly associated with increasing hearing threshold in the high frequencies. After adjusting for age, serum folate (correlation coefficient = -0.01, P = 0.01) was significant, while vitamin B12 (correlation coefficient = -0.01, P = 0.74) was not.

CONCLUSION

Serum folate was significantly lower among elderly with ARHL. Trials on nutritional supplementation may substantiate the role of serum folate in ARHL.

Serum vitamin B12 and folate status in patients with inflammatory bowel diseases

BACKGROUND

The aims of this study were to investigate the prevalence of serum vitamin B(12) and folate abnormalities in patients with inflammatory bowel diseases (IBD) and to identify risk factors associated with B12 and folate abnormalities in this entity.

METHODS

138 patients with IBD (45 Crohn's disease and 93 ulcerative colitis) and 53 healthy subjects were enrolled into the study. Fasting serum B12 and folic acid levels were measured and clinical data regarding inflammatory bowel diseases were gathered.

RESULTS

While the mean serum B(12) concentration in CD patients was 281+/-166pg/ml, the mean serum vitamin B12 concentration in UC patients was 348+/-218pg/ml (p=0.224). The number of patients with vitamin B12 deficiency in the CD group was greater than the number of patients with UC [n=10 (22%) vs. n=4 (7.5%), p=0.014]. The number of patients (n=10, 22%) with B12 deficiency in the CD group was also greater than controls (n=4, 7.5%) (p=0.039). With regard to folate levels, the median serum folate level was 7.7+/-5.3ng/ml in CD patients, 8.6+/-8.3ng/ml in UC patients and 9.9+/-3.3ng/ml in the control group (p=n.s.). Patients with a prior ileocolonic resection had an abnormal B12 concentration compared to patients without surgery (p=0.008). In CD patients, ileal involvement was the only independent risk factor for having a low folate level.

CONCLUSION

Serum vitamin B12 and folate deficiencies are common in patients with CD compared to UC patients and controls. In CD patients, prior small intestinal surgery is an independent risk factor for having a low serum vitamin B12 level.

Prevalence of anaemia, deficiencies of iron and folic acid and their determinants in Ethiopian women

A cross-sectional community-based study with analytic component was conducted among Ethiopian women during June-July 2005 to assess the magnitude of anaemia and deficiencies of iron and folic acid and to compare the factors responsible for anaemia among anaemic and non-anaemic cases. In total, 970 women, aged 15-19 years, were selected systematically for haematological and other important parameters. The overall prevalence of anaemia, iron deficiency, iron-deficiency anaemia, deficiency of folic acid, and parasitic infestations was 30.4%, 50.1%, 18.1%, 31.3%, and 13.7% respectively. Women who had more children aged less than five years but above two years, open-field toilet habits, chronic illnesses, and having intestinal parasites were positively associated with anaemia. Women who had no formal education and who did not use contraceptives were negatively associated with anaemia. The major determinants identified for anaemia were chronic illnesses [adjusted odds ratio (AOR) = 1.1, 95% confidence interval (CI) 1.15-1.55), deficiency of iron (AOR = 0.4, 95% CI 0.35-0.64), and deficiency of folic acid (AOR = 0.5, 95% CI 0.50-0.90). The odds for developing anaemia was 1.1 times more likely among women with chronic illnesses, 60% more likely in the iron-deficient and 40% more likely in the folic acid-deficient than their counterparts. One in every three women had anaemia and deficiency of folic acid while one in every two had iron deficiency, suggesting that deficiencies of both folic acid and iron constitute the major micronutrient deficiencies in Ethiopian women. The risk imposed by anaemia to the health of women ranging from impediment of daily activities and poor pregnancy outcome calls for effective public-health measures, such as improved nutrient supplementation, health education, and timely treatment of illnesses.

Deficiencies of folate and vitamin B12 do not affect fracture healing in mice

PURPOSE

Recently, hyperhomocysteinemia has been shown to be associated with impaired fracture healing in mice. The main causes for hyperhomocysteinemia are deficiencies of folate and vitamin B12. However, there is no information on whether deficiencies of these B vitamins are affecting bone repair, too.

METHODS

We used two groups of mice to investigate the impact of folate and vitamin B12 deficiency on fracture healing: mice of the first group were fed a folate- and vitamin B12-deficient diet (n=14), while mice of the second group received an equicaloric control diet (n=13). Four weeks after stabilizing a closed femur fracture, bone repair was analyzed by histomorphometry and biomechanical testing. In addition, serum concentrations of homocysteine, folate, vitamin B12, the bone formation marker osteocalcin (OC), and the bone resorption marker collagen I C-terminal crosslaps (CTX) were measured.

RESULTS

Serum analyses revealed significantly decreased concentrations of folate and vitamin B12 in animals fed the folate- and vitamin B12-deficient diet when compared to controls. This was associated with a moderate hyperhomocysteinemia in folate- and vitamin B12-deficient mice, while no hyperhomocysteinemia was found in controls. Three-point bending tests showed no significant differences in callus stiffness between bones of folate- and vitamin B12-deficient animals and those of control animals. In accordance, the histomorphometric analysis demonstrated a comparable size and tissue composition of the callus, and also serum markers of bone turnover did not differ significantly between the two groups.

CONCLUSIONS

We conclude that folate and vitamin B12 deficiency does not affect bone repair in mice.

[Prevalence of vitamin B-12 deficiency in older adults]

BACKGROUND

There is a correlation between aging and the decrease of plasma levels of vitamin B-12.

AIM

To determine the prevalence of vitamin B-12 and folate deficiency and its hematological impact among older adults (AM).

MATERIAL AND METHODS

Cross-sectional study, in 1028 subjects aged 65 to 87years, living in community and evaluated between 2005 and 2008. Percentile distribution of vitamin B-12, folate, hemoglobin, packed red cell volume and mean cell volume by gender and age were analyzed. Deficiency was defined as vitamin B-12 levels < 148 pmol/L, marginal deficiency as vitamin B-12 levels < 221 pmol/L, anemia was defined as a hemoglobin < 13 and 12 g/dL among men and women, respectively.

RESULTS

The prevalence of vitamin B-12 deficiency was 12% and the figure for marginal deficiency was 25.4%. Males were more affected than females (p < 0.001). The frequency of anemia was 8.6%o, and was higher among women (p = 0.004).

CONCLUSIONS

There is a high prevalence of full blown and marginal deficit of vitamin B-12 among the elderly. This deficiency should be considered for correction through public nutrition policies.

Anaemia, folate, zinc and copper deficiencies among adolescent schoolgirls in eastern Sudan

Anaemia is a widespread problem especially in the tropics. Among adolescent girls, it has negative consequences on growth, school performance, morbidity and reproductive performance. A cross-sectional study was conducted to investigate the prevalence of anaemia, iron, folate, zinc and copper deficiencies amongst adolescent schoolgirls in New Halfa, eastern Sudan, and to examine the relationship of these micronutrients with haemoglobin (Hb) levels. Out of 187 adolescent schoolgirls, 181 (96.8%) had anaemia (Hb<12 g/dl); 21% had mild anaemia (Hb 11.0-11.9 g/dl); 66.8.1% had moderate anaemia (Hb 8.0-10.9 g/dl), and 12.1% had severe anaemia (Hb<8 g/dl), respectively. Iron deficiency (S-ferritin<12 μg/l), iron deficiency anaemia (<12 m/dl and S- ferritin<12 μg/l) and folate deficiency (S-folate<3 ng/ml) were prevalent in 17.6%, 16.5% and 69% of these girls, respectively. Nine percent and 5.9% of these girls had zinc (<75 μg/ml) and copper deficiency (<75 μg/ml), respectively. Twenty-six (14%) girls had ≥ 2 micronutrient deficiencies. S-ferritin and zinc were significantly lower in patients with severe anaemia. Haemoglobin levels were significantly positively correlated with zinc levels (r=0.161, P=0.03) and with copper levels (r=0.151, P=0.03). Thus, interventions are required to prevent and control anaemia in this setting. Further research is needed.

Serum folate and vitamin B12 status in healthy Iranian adults

To assess the serum folate and vitamin B12 status in healthy Iranian adults, we designed a population-based cross-sectional study of 1200 individuals aged 20-80 years. Finally 984 participants (507 men and 477 women) were assessed. The mean serum folate was 4.61 (SD 2.40) ng/mL and the mean serum vitamin B12 level was 265.6 (SD 170.9) pg/mL. Overall 1.0% were folate deficient and 25.8% had low vitamin B12 levels according to the manufacturer's reference ranges (folate < 1.5 ng/mL and vitamin B12 < 160 pg/mL). The mean serum folate and vitamin B12 levels were significantly lower in men. The prevalence of vitamin B12 deficiency was considerably higher than folate deficiency. Implementation of preventive measures seems to be necessary.

Psychotic disorder and extrapyramidal symptoms associated with vitamin B12 and folate deficiency

Vitamin B12 and folate deficiency causing neuropsychiatric and thrombotic manifestations, such as peripheral neuropathy, subacute combined degeneration of cord, dementia, ataxia, optic atrophy, catatonia, psychosis, mood disturbances, myocardial infarction and portal vein thrombosis are well known. This present report highlights an unusual presentation of vitamin B12 deficiency-psychotic disorder, extrapyramidal symptoms in a 12-year-old boy. His symptoms responded to parenteral vitamin B12 therapy. So with this report we emphasized that serum vitamin B12 and folate levels should be measured, especially in those patients who present with other known neuropsychiatric features of vitamin B12 and folate deficiency.

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.

Preferential response of glutathione-related enzymes to folate-dependent changes in the redox state of rat liver

BACKGROUND

Oxidative stress likely constitutes an important contributing factor in the onset of degenerative diseases associated with folate deficiency. Direct, as well as homocysteine-linked, antioxidant properties of folate could explain its preventive effect on these pathologies.

AIM OF THE STUDY

Our study aimed at determining the changes in the redox status of adult rats as a function of folate intake.

METHODS

Adult male rats were pair-fed for 4 weeks with a semi-synthetic diet containing 0, 0.5, 1.5, 8 or 20 mg of folic acid/kg. Folate and homocysteine concentrations, redox status markers and antioxidant enzyme activities were measured in the plasma and/or liver of the rats. A principal component analysis of the overall data was performed to draw a general scheme of the changes observed between the conditions.

RESULTS

Folate deficiency caused increased homocysteinemia and features of oxidative stress including reduced plasma antioxidant capacity together with increased lipid peroxidation in liver and heart. This was associated with an increase in the specific activity of several enzymes involved in liver glutathione metabolism (glutathione peroxidase, glutathione reductase and glutathione S-transferase), suggesting an adaptive tissue response to the oxidative stress induced by folate deficiency. In contrast, no such variation was observed for hepatic superoxide dismutase and catalase.

CONCLUSION

Despite no changes in hepatic levels of total glutathione, our findings indicate that glutathione-dependent antioxidant pathways could be particularly involved in the compensatory mechanism committed by liver to counteract the oxidative stress induced by folate deficiency. They also suggest that folate supplementation may not be associated with a better antioxidant protection of rats.