Serum Vitamin B12 Concentrations Research Articles

Association of Cognitive Impairment with Combinations of Vitamin B12–Related Parameters

Low vitamin B₁₂ concentrations have been associated with higher risks of cognitive impairment, but whether these associations are causal is uncertain. The associations of cognitive impairment with combinations of vitamin B₁₂, holotranscobalamin, methylmalonic acid, and total homocysteine, and with the vitamin B₁₂ transport proteins transcobalamin and haptocorrin, have not been previously studied. We performed a population-based cross-sectional study of 839 people 75 years old or older. We examined the association of cognitive function as measured by mini-mental state examination scores, with markers of vitamin B₁₂ status. Spearman correlations as well as multivariate-adjusted odds ratios and 95% CIs for cognitive impairment were calculated for extreme thirds of serum concentrations of vitamin B₁₂, holotranscobalamin, methylmalonic acid, total homocysteine, combination of these markers in a wellness score, heaptocorrin, and transcobalamin for all data and with B₁₂ analogs in a nested case-control study. Cognitive impairment was significantly associated with low vitamin B₁₂ [odds ratio 2.3 (95% CI 1.2-4.5)]; low holotranscobalamin [4.1 (2.0-8.7)], high methylmalonic acid [3.5 (1.8-7.1)], high homocysteine [4.8 (2.3-10.0)] and low wellness score [5.1 (2.61-10.46)]. After correction for relevant covariates, cognitive impairment remained significantly associated with high homocysteine [4.85 (2.24-10.53)] and with a low wellness score [5.60 (2.61-12.01)] but not with transcobalamin, haptocorrin, or analogs on haptocorrin. Cognitive impairment was associated with the combined effects of the 4 biomarkers of vitamin B₁₂ deficiency when included in a wellness score but was not associated with binding proteins or analogs on haptocorrin.

Multiple micronutrient supplementation improves vitamin B12and folate concentrations of HIV infected children in Uganda: a randomized controlled trial

BackgroundThe effect of multiple micronutrient supplementation on vitamin B12 and folate has hither to not been reported in African HIV infected children. This paper describes vitamin B12 and folate status of Ugandan HIV infected children aged 1-5 years and reports the effect of multiple micronutrient supplementation on serum vitamin B12 and folate concentrations.MethodsOf 847 children who participated in a multiple micronutrient supplementation trial, 214 were assessed for vitamin B12 and folate concentrations pre and post supplementation. One hundred and four children were randomised to two times the recommended dietary allowance (RDA) of a 14 multiple micronutrient supplement (MMS) and 114 to a 'standard of care' supplement of 6 multivitamins (MV). Serum vitamin B12 was measured by an electrochemiluminescence immunoassay and folate by a competitive protein-binding assay using Modular E (Roche) automatic analyzer. Vitamin B12 concentrations were considered low if less than 221picomoles per litre (pmol/L) and folate if < 13.4 nanomoles per litre (nmol/L). The Wilcoxon Signed Ranks test was used to measure the difference between pre and post supplementation concentrations.ResultsVitamin B12 was low in 60/214 (28%) and folate in 62/214 (29.0%) children. In the MMS group, the median concentration (IQR) of vitamin B12 at 6 months was 401.5 (264.3 - 518.8) pmol/L compared to the baseline of 285.5 (216.5 - 371.8) pmol/L, p < 0.001. The median (IQR) folate concentrations increased from 17.3 (13.5 - 26.6) nmol/L to 27.7 (21.1 - 33.4) nmol/L, p < 0.001. In the 'standard of care' MV supplemented group, the median concentration (IQR) of vitamin B12 at 6 months was 288.5 (198.8 - 391.0) pmol/L compared to the baseline of 280.0 (211.5 - 386.3) pmol/L while the median (IQR) folate concentrations at 6 months were 16.5 (11.7 - 22.1) nmol/L compared to 15.7 (11.9 - 22.1) nmol/L at baseline. There was a significant difference in the MMS group in both vitamin B12 and folate concentrations but no difference in the MV group.ConclusionsAlmost a third of the HIV infected Ugandan children aged 1-5 years had low serum concentrations of vitamin B12 and folate. Multiple micronutrient supplementation compared to the 'standard of care' supplement of 6 multivitamins improved the vitamin B12 and folate status of HIV infected children in Uganda.Trial registrationhttp://ClinicalTrials.govNCT00122941)

Physiologic changes in homocysteine metabolism in pregnancy: A longitudinal study in Spain

Objective The aim was to investigate whether pregnancy-induced changes in total homocysteine (tHcy) are associated with folate and vitamin B12 nutritional status, genetic C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) enzyme, and gestation outcome at a time when folic acid supplementation started to be recommended in the Spanish health system. Methods In total 154 pregnant women were recruited from among gynecologic patients of the Alcorcón Public Hospital Outpatient Clinic (Madrid, Spain). Blood tests were performed at weeks 15, 24, and 32 of pregnancy. Total Hcy, folate, and vitamin B12 serum fasting concentrations were measured using an IMx system. Genotype analyses were done by polymerase chain reaction/restriction fragment/length polymorphism analysis. Results Folate and vitamin B12 serum concentrations decreased significantly ( P < 0.01) through pregnancy and reached the lowest values in the third trimester. Serum tHcy concentrations were significantly ( P < 0.01) lower in the second trimester but increased in the third trimester. Frequencies of MTHFR C667T genotype were CC (35.7%), CT (57.2%), and TT (7.1%). Total Hcy concentration was not statistically influenced by maternal genotype. Plasma folate was the single negative predictor of maternal tHcy in the first trimester of pregnancy; 11.1% of gestations resulted in intrauterine growth restriction, 7.9% in gestational diabetes mellitus, and 4.8% in gestational hypertension. No significant differences in serum folate, vitamin B12, or tHcy concentrations were found in complicated pregnancies and these were unrelated to MTHFR genotype. Conclusion Although tHcy seems to be physiologically low in this Spanish population and unrelated to folate and B12 nutritional status, C677T MTHFR genotype, and some pregnancy complications, we support the statement that appropriate folate concentration may be important throughout pregnancy to prevent abnormalities associated with altered status (e.g., neural tube defects). According to our study, supplementation with folic acid seems to achieve this purpose because diet alone may be insufficient. In addition, a poor vitamin B12 status, as measured by plasma levels, may indicate that supplementation of both vitamins is needed.

Diarrhea and Novel Dietary Factors Emerge as Predictors of Serum Vitamin B12 in Panamanian Children

The role of gastrointestinal infection as a factor determining vitamin B12 status in populations with low intake of animal-source foods is unclear. To determine dietary adequacy and serum concentrations of vitamin B12 in an extremely impoverished indigenous population of Panamanian children aged 12 to 60 months, and to identify predictors of both dietary and serum vitamin B12. A previous community-based survey provided the usual dietary intake and personal, household, and infection (Ascaris and diarrheal disease) information for 209 weaned children. Serum vitamin B12 was assayed using electrochemiluminescence for 65 of these children. Children with adequate or inadequate dietary vitamin B12 intake were compared, and predictors of dietary and serum vitamin B12 were identified using stepwise regression analyses of one index child per household. Dietary vitamin B12 intake was inadequate in 43% of children; these children were poorer, had less frequent diarrhea, and obtained a higher percentage of their energy from carbohydrate than children with adequate intake. Energy intake positively predicted dietary vitamin B12 intake. In contrast, serum vitamin B12 concentrations were normal in all but 3% of the children. Serum vitamin B12 was positively associated with weekly servings of fruit, corn-based food, and name (a traditional starchy food), but not with animal-source foods. Finally, serum vitamin B12 was not associated with Ascaris intensity but was lowered with increasing frequency of diarrhea. Although inadequate dietary intake of vitamin B12 was common, most serum values were normal. Nevertheless, diarrheal disease emerged as a negative predictor of serum vitamin B12 concentration.

Relationship Between Genetic Polymorphisms of Methylenetetra hydrofolate Reductase (C677T, A1298C, and G1793A) as Risk Factors for Idiopathic Male Infertility

The human methylenetetrahydrofolate reductase (MTHFR) gene plays a crucial role in folate metabolism. Data regarding the influence of MTHFR gene polymorphisms on male fertility status are scarce and conflicting. We determined associations between 3 MTHFR gene polymorphisms (C677T, A1298C, and G1793A), serum folate, and total homocysteine (tHcy) levels, with male fertility status and semen parameters. MTHFR genotypes were determined using polymerase chain reaction restriction fragment length polymorphism (PCR-RLFP) technique and serum tHcy, folate, and vitamin B12 concentrations were measured in 164 men with idiopathic infertility and 328 healthy participants. There was a significant difference in genotype frequency distribution of MTHFR C677T polymorphism between infertile patients and controls (P = .004). The 677T allele carriers (TC or TT) had a significantly increased risk of infertility compared with the CC homozygotes (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.21-2.75, and OR = 2.68, 95% CI = 1.84-3.44, respectively), in a logistic regression model after adjustment for confounding factors. Men with the 677T, 1298C, and 1793G alleles showed significantly higher serum tHcy and lower folate levels (all Ps < .01). We found a positive correlation between serum folate concentrations and sperm density (r = .74, P = .001), percentage of sperm with progressive motility (r = .68, P = .001), as well as percentage of sperm with normal morphology (r = .72, P = .001). MTHFR C677T polymorphism is associated with an increased risk of idiopathic male infertility. Further study on the biologic role that this polymorphism plays in the development of infertility may lead to better understanding of the etiology of impaired spermatogenesis.

Vitamin B12 Status in Males and Females of different Age Groups

Problem statement: Vitamin B deficiency remains widespread in many countries including Jordan, mainly due to inadequate dietary intake of vitamin B and absorption problems. Approach: Few researches on vitamin B12 status in healthy subjects are carried out. Thus, the aim of this study was to evaluate the serum levels of vitamin B12 in healthy Jordanian subjects living in the city of Ma'an. Randomized samples involving 511 healthy participants aged between 15-80 years whom referred for routine laboratory check up at the medical center of Al-Hussein Bin Talal University (AHU) in Jordan, were subjected to a health screening and then they provided a blood sample. Serum vitamin B12 concentration was determined using the fully automated Abbott AxSYM B12 assay, the accuracy and precision of this method was evaluated using certified reference materials. Results: Prevalence of low vitamin for 15-24-year-old, 25-34-year-old and over 34-year-old age groups among both males 2.7, 2.9 and 5.1% and females 5.1, 3.9 and 5.8% respectively were not significantly lower than those were not B12 deficient (P = 0.57 and P = 0.52, respectively). The highest prevalence was considered in both male and female over 34-year-old age group which increased by ageing. Conclusion/Recommendations: This study revealed that the prevalence of low vitamin B12 levels are considerably lower than other communities. One possible explanation of these observations is that Jordanians eat adequate animal products to increase the daily intake of vitamin B12. Further studies are needed to confirm these results.

Chemistry behind Vegetarianism

This review summarizes the effect of a habitual vegetarian diet on clinical complications in relation to chemistry and biochemistry. Omnivores have a significantly higher cluster of cardiovascular risk factors compared with vegetarians, including increased body mass index, waist to hip ratio, blood pressure, plasma total cholesterol (TC), triacylglycerol and LDL-C levels, serum lipoprotein(a) concentration, plasma factor VII activity, ratios of TC/HDL-C, LDL-C/HDL-C and TAG/HDL-C, and serum ferritin levels. Compared with omnivores, vegetarians, especially vegans, have lower serum vitamin B₁₂ concentration and n-3 polyunsaturated fatty acid (PUFA) levels in the tissue membrane phospholipids, which are associated with increased collagen and ADP stimulated ex vivo whole blood platelet aggregation, plasma 11-dehydrothromboxane B₂, and homocysteine levels and decreased plasma HDL-C. This may be associated with an increased thrombotic and atherosclerotic risk. It is suggested that vegetarians, especially vegans, should increase their dietary n-3 PUFA and vitamin B₁₂ intakes.

Betaine reduction of hyperhomocysteinemia and enhancement of 5-hydroxyindoleacetic acid in ethanol-induced hyperhomocysteinemia in rabbits.

Hyperhomocysteinemia is a hypothesis for the association of homocysteine with cerebrovascular diseases, neurodegenerative diseases and depression of mood. Thus, we examined whether oral betaine can act as a preventive agent in ethanol-induced hyperhomocysteinemia on the monoaminergic system. A total of 32 New Zealand White rabbits were divided into four groups (n=8); the Control group (C). The Ethanol group (E) was administered ethanol at a dosage of 4 g/kg daily. The Betaine group (B) received betaine at a dosage 1.5% (w/w) of the diet daily, and the Betaine and Ethanol group (BE after one hour the rabbits received ethanol at a dosage of 4 g/kg daily. Blood samples were taken in the morning of the day before beginning treatment (0.0 day) and on the 30th, 60th and 90th day of the treatment. Serum folate and vitamin B12 levels were determined using a radioimmunoassay, total plasma homocysteine (tHcy) level was determined by homocysteine EIA kit, and 5- hydroxyindoleacetic acid (5-HIAA) of plasma was measured with HPLC-ECD. There was a significant negative correlation between 5-HIAA and tHcy in the E group (r=-0.473, P=0.02), and compared to the E group the concentrations of 5-HIAA in the B&E group increased considerably (p<0.05). In contrast to the E group, significantly high concentrations of 5-HIAA were observed in the B and C groups. While the serum concentrations of vitamin B12 showed no significant difference in the B&E group on the 90th day compared to the control group, the serum concentrations of folate on the 90th day differed significantly (p<0.05) . However, no significant difference was observed between tHcy and gender. Overall, oral pretreatment with betaine significantly prevented ethanol-induced hyperhomocysteinemia, subsequently increasing 5-HIAA in the plasma as well as vitamin B12 and folate in the serum. Thus, betaine may be recommended as a pretreatment method for depressive patients with alcoholism. Key words: Betaine, hyperhomocysteinemia, 5-HIAA, ethanol, vitamin B12, folate.

Common polymorphisms in methylenetetrahydrofolate reductase gene are associated with risks of cervical intraepithelial neoplasia and cervical cancer in women with low serum folate and vitamin B12

We evaluated associations between folate, vitamin B12, and the methylenetetrahydrofolate reductase (MTHFR) gene, and risk of cervical intraepithelial neoplasia (CIN) and cervical cancer. This multicenter case-control study enrolled 927 Korean women (440 controls, 165 patients with CIN 1, 167 patients with CIN 2/3, and 155 patients with cervical cancer, aged 20-75years). Patients with cervical cancer had significantly lower median serum folate and vitamin B12 concentrations vs. controls. Higher serum folate was significantly associated with lower cervical cancer risk (p for linear trend=0.0058) with a trend for a lower CIN risk after multivariate adjustment. Low folate and the MTHFR 677 C>T variant were associated with a higher risk for CIN2/3 and cervical cancer vs. wild-type or heterozygous genotypes with high folate [OR, 2.39 (1.18-4.85) and 3.19 (1.43-7.13)]. Low vitamin B12 and the MTHFR 677 C>T variant also were associated with a higher risk for CIN 2/3 and cervical cancers [OR, 2.52 (1.17-5.42) and 2.40 (1-5.73)] vs. wild-type or heterozygous status with high vitamin levels. Serum folate concentration is inversely associated with the risk of cervical cancer, and the MTHFR variant genotype may increase CIN and cervical cancer risk in women with low folate or vitamin B12 status.

Serum concentrations of vitamin B12 and folate in British male omnivores, vegetarians and vegans: results from a cross-sectional analysis of the EPIC-Oxford cohort study

Background/ObjectivesVegans and to a lesser extent vegetarians have low average circulating concentrations of vitamin B12; however, the relation between factors such as age or time on these diets and vitamin B12 concentrations is not clear. The objectives were to investigate differences in serum vitamin B12 and folate concentrations between omnivores, vegetarians and vegans and to ascertain whether vitamin B12 concentrations differed by age and time on the diet.Subjects/MethodsA cross-sectional analysis involving 689 men (226 omnivores, 231 vegetarians and 232 vegans) from the European Prospective Investigation into Cancer and Nutrition Oxford cohort.ResultsMean serum vitamin B12 was highest among omnivores (281, 95% CI: 270-292 pmol/l), intermediate in vegetarians (182, 95% CI: 175-189 pmol/l), and lowest in vegans (122, 95% CI: 117-127 pmol/l). Fifty-two percent of vegans, 7% of vegetarians and one omnivore were classified as vitamin B12 deficient (defined as serum vitamin B12 < 118 pmol/l). There was no significant association between age or duration of adherence to a vegetarian or a vegan diet and serum vitamin B12. In contrast, folate concentrations were highest among vegans, intermediate in vegetarians, and lowest in omnivores, but only two men (both omnivores) were categorised as folate deficient (defined as serum folate < 6.3 nmol/l).ConclusionVegans have lower vitamin B12 concentrations, but higher folate concentrations, than vegetarians and omnivores. Half of the vegans were categorised as vitamin B12 deficient and would be expected to have a higher risk of developing clinical symptoms related to vitamin B12 deficiency.

Folic Acid and Vitamin B12 Supplementation Improves Coronary Flow Reserve in Elderly Subjects with Vitamin B12 Deficiency

Major cardiovascular risk factors including hyperhomocysteinemia are frequently associated with decreased coronary flow reserve (CFR), an important physiological parameter of the coronary circulation. This study was designed to determine whether folate (5 mg) and vitamin B12 (500 μg) supplementation in elderly patients with vitamin B12 deficiency improved CFR, while reducing homocysteine levels. Forty-four patients aged >65 years showing serum vitamin B12 concentrations <180 mg/dL were randomized to take either oral folate (5 mg) plus vitamin B12 (500 μg) supplementation (n = 24) or placebo (n = 20) for 8 weeks. The study course consisted of two visits: visit 1 (pretreatment) included the baseline assessment of laboratory profile and CFR values with trans-thoracic Doppler echocardiography. Visit 2 was scheduled 8 weeks later to repeat CFR and laboratory tests after therapy. In the treatment arm, oral supplementation with folate and vitamin B12 significantly improved total cholesterol, serum folate, serum vitamin B12, homocysteine, and insulin resistance. At 8 weeks, the treatment group had a significant increase from baseline in CFR values (baseline: 1.7 ± 0.2; postttreatment: 2.1 ± 0.2, p <0.001) that was not seen in the placebo group (baseline: 1.6 ± 0.2; posttreatment: 1.6 ± 0.2; P = ns). In this study of elderly subjects with vitamin B12 deficiency, supplementation with folate and vitamin B12 was associated with a significant improvement in CFR values.

Serological Differences in Folate/Vitamin B12 in Pregnancies Affected by Neural Tube Defects

Laboratory evidence is presented of significant associations between reduced maternal serum folate and vitamin B12 levels and neural tube birth defects (NTD) compared to referents. This was an incident case-control study. Cases of neural tube defects (including anencephaly and open spina bifida) diagnosed in residents within 100 miles of the US-Mexico border from January 1993 to October 2000 were eligible. Most cases were diagnosed in utero upon visits to clinics, obstetrical or genetic expert offices. Cases identified upon hospital admission or at delivery were also eligible. Cases identified after discharge were not. Controls were matched on geographic region, maternal age, race/ethnicity, gestational age, and type of health insurance (including none). Three hundred eighty-two border area residents (107 cases and 275 individually matched controls) provided biological specimens. Median folate concentrations for case mothers were 36% lower than controls (9.8 ng/mL vs. 15 ng/mL). Maternal serum folate concentrations in quartiles above 9.5 ng/mL indicated significantly reduced risk (OR = 0.4, OR = 0.3, and OR = 0.2). Likewise, the risk for NTD decreased (OR = 0.4, OR = 0.3, and OR = 0.2) in quartiles of sera B12 concentrations above 246 pg/mL. Physician attention is invited to significantly lower concentrations of serum folate and vitamin B12 in women with NTD-affected pregnancies. This study assayed sera samples from women while still pregnant or immediately after delivery. The confounding effect of reduced folate and B12 levels with other biological and chemical exposures will be addressed in subsequent communications.

Considering the Case for Vitamin B12 Fortification of Flour

Reasons to fortify flour with vitamin B12 are considered, including the high prevalence of depletion and deficiency of this vitamin that occurs in persons of all ages in resource-poor countries and in the elderly in wealthier countries, and the adverse functional consequences of poor vitamin B12 status. From a global perspective, the main cause of inadequate intake and status is a low intake of animal-source foods; even lacto-ovo vegetarians have lower serum vitamin B12 concentrations than omnivores, and for various reasons many populations have limited consumption of animal-source foods. Infants are vitamin B12-depleted from early infancy if their mothers' vitamin B12 status and intake are poor during pregnancy and lactation. Even in the United States, more than 20% of the elderly have serum vitamin B12 concentrations that indicate depletion, and an additional 6% have deficiency, primarily due to gastric atrophy, which impairs the absorption of the vitamin from food but usually not from supplements or fortified foods. Although the evidence is limited, it shows that fortified flour, consumed as bread, can improve vitamin B12 status. Where vitamin B12 fortification is implemented, the recommendation is to add 20 microg/kg flour, assuming consumption of 75 to 100 g flour per day, to provide 75% to 100% of the Estimated Average Requirement; the amount of the vitamin that can be added is limited by its cost. The effectiveness of this level of addition for improving vitamin B12 status in programs needs to be determined and monitored. In addition, further research should evaluate the bioavailability of the vitamin from fortified flour by elderly people with food cobalamin malabsorption and gastric atrophy.

Vitamin B12 Deficiency is Linked with Long-Term Use of Proton Pump Inhibitors in Institutionalized Older Adults: Could a Cyanocobalamin Nasal Spray be Beneficial?

The purpose of this study was to determine whether institutionalized older individuals taking proton pump inhibitors (PPI) for more than 12 months were more likely to have vitamin B12 deficiency than individuals not taking PPI, and whether cyanocobalamin nasal spray would improve their vitamin B12 status. Participants were long-term care residents aged 60–89 years. PPI users (n = 17) were treated with cyanocobalamin nasal spray for 8 weeks; non-PPI users (n = 19) were not treated but were followed for the same time duration. Serum samples from all subjects were analyzed for vitamin B12 and serum methylmalonic acid (sMMA) at baseline and the end of the 8-week treatment. There was a significant difference in mean vitamin B12, sMMA, and frequency of deficiency between control and intervention groups at baseline. After treatment, there was an increase (p = 0.012) in serum vitamin B12 concentration, and a decrease (p = 0.004) in frequency of deficiency in PPI users. Thus, we found that institutionalized older individuals on PPI for more than 12 months may be more likely to be vitamin B12 deficient than non-PPI users. Additionally, treatment of PPI users with cyanocobalamin nasal spray for 8 weeks could improve vitamin B12 status.

Indian women with higher serum concentrations of folate and vitamin B12 are significantly less likely to be infected with carcinogenic or high-risk (HR) types of human papillomaviruses (HPVs)

Studies conducted in the USA have demonstrated that micronutrients such as folate and vitamin B12 play a significant role in modifying the natural history of high-risk human papillomaviruses (HR-HPVs), the causative agent for developing invasive cervical cancer (CC) and its precursor lesions. The purpose of the current study was to investigate whether these micronutrients have similar effects on HR-HPV infections in Indian women. The associations between serum concentrations of folate and vitamin B12 and HR-HPV infections were evaluated in 724 women who participated in a CC screening study in the southern state of Andhra Pradesh, India. Serum folate and vitamin B12 concentrations were measured by using a competitive radio-binding assay. Digene hybrid capture 2 (HC2) assay results were used to categorize women into two groups, positive or negative for HR-HPVs. Unconditional logistic regression models specified a binary indicator of HC2 (positive/negative) as the dependent variable and serum folate concentrations combined with serum vitamin B12 concentrations as the independent predictor of primary interest. Models were fitted, adjusting for age, education, marital status, parity, type of fuel used for cooking and smoking status. Women with higher concentrations of serum folate (>6 ng/mL) and vitamin B12 (>356 pg/mL) were at lower risk of being positive for HR-HPVs compared to those with serum folate ≤6 ng/mL and serum vitamin B12 ≤ 356 pg/mL (odds ratio = 0.26; 95% confidence interval: 0.08-0.89; P = 0.03). These results demonstrated that improving folate and vitamin B12 status in Indian women may have a beneficial impact on the prevention of CC. Micronutrient based interventions for control of HR-HPV infections may represent feasible alternatives to vaccine based approaches to HPV disease prevention, which are currently unaffordable for use in resource limited areas in rural India.

Progressive myelopathy with hyperintensity on T2-weighted spinal MRI

The patient had a high titer of anti-human T lymphotrophic virus type-1 (HTLV-1) antibodies both in the plasma ( 262,144; normal < 16) and in the CSF ( 262,144; normal < 16), on the basis of which HTLV-1 -associated myelopathy (HAM) was diagnosed. Serum concentrations of vitamin B12 (243 pg/mL; normal: 233–914 pg/mL), folate (5.3 ng/mL; normal: 3.6–12.9 ng/mL), and angiotensin-converting enzyme 1 (13.2 U/L; normal: 7.7–29.4 U/ L) were normal. Spinal MRI in patients with HAM is characterized by thoracic cord atrophy without intensity changes and gadolinium enhancement. Recently, however, patients with HAM with high-signal-intensity areas on T2-weighted spinal MRI have been

Lifestyle and genetic determinants of folate and vitamin B12 levels in a general adult population

Danish legislation regarding food fortification has been very restrictive resulting in few fortified food items on the Danish market. Folate and vitamin B12 deficiency is thought to be common due to inadequate intakes but little is known about the actual prevalence of low serum folate and vitamin B12 in the general population. The aim of the present study was to evaluate the folate and vitamin B12 status of Danish adults and to investigate associations between vitamin status and distinct lifestyle and genetic factors. The study included a random sample of 6784 individuals aged 30-60 years. Information on lifestyle factors was obtained by questionnaires and blood samples were analysed for serum folate and vitamin B12 concentrations and several genetic polymorphisms. The overall prevalence of low serum folate ( < 6.8 nmol/l) was 31.4 %. Low serum folate was more common among men than women and the prevalence was lower with increasing age. Low serum folate was associated with smoking, low alcohol intake, high coffee intake, unhealthy diet, and the TT genotype of the methylenetetrahydrofolate reductase (MTHFR)-C677T polymorphism. The overall prevalence of low serum vitamin B12 ( < 148 pmol/l) was 4.7 %. Low serum vitamin B12 was significantly associated with female sex, high coffee intake, low folate status, and the TT genotype of the MTHFR-C677T polymorphism. In conclusion, low serum folate was present in almost a third of the adult population in the present study and was associated with several lifestyle factors whereas low serum concentrations of vitamin B12 were less common and only found to be associated with a few lifestyle factors.

Rate of T alleles and TT genotype at MTHFR 677C‐&gt;T locus or C alleles and CC genotype at MTHFR 1298A‐&gt;C locus among healthy subjects in Turkey: impact on homocysteine and folic acid status and reference intervals

Methylenetetrahydrofolate reductase (MTHFR) is important for folate and homocysteine (Hcy) metabolism. MTHFR 677C->T and 1298A->C MTHFR are two most common mutations which can affect folate and total homocysteine (tHcy) status. This study was designed to determine the rate of MTHFR 677C->T and 1298A->C mutations, and their influence on serum folate, Hcy and vitamin B12 status and the reference intervals in 402 healthy Turkish adults. The rate of MTHFR 677C->T or 1298A->C mutations was 50.7% or 54.7%, respectively. The MTHFR 677C->T mutation-specific reference intervals for serum folate and tHcy were characterized by marked shifts in their upper limits. In homozygote subjects for MTHFR 677C->T serum folate concentration was lower and serum tHcy concentration was higher than those in the wild genotype; all subjects had lower serum folate and 54% of the subjects had higher tHcy concentrations than the cutoff values of <or=10 nmol/L and >or=12 micromol/L, respectively. Serum vitamin B12 status was similar in all genotypes. Serum tHcy concentrations were inversely correlated with serum folate and vitamin B12 concentrations in all genotypes. These data show that the rate of MTHFR 677C->T and 1298A->C mutations is very high in Turks and serum folate and tHcy status are impaired by these mutations.

Clinical study of tongue pain: Serum zinc, vitamin B12, folic acid, and copper concentrations, and systemic disease

The aim of this retrospective study of patients with tongue pain who showed no improvement after initial treatment and examination was to find out if their lack of response correlated with serum concentrations of zinc, vitamin B12, folic acid, and copper, and if it was associated with coexisting systemic diseases. We studied 311 patients for whom we had data about serum concentrations of these elements, and recorded whether they had any systemic diseases and were taking medicines regularly. One patient (0.3%) had a copper concentration outside the reference range; 2 patients (0.6%) had folic acid concentrations outside the reference range. The corresponding number for vitamin B12 was 5 (2%), and for zinc 30 (10%). The systemic diseases with the highest rates were: hyperlipidaemia ( n = 53, 17%), gastritis or gastric ulcer ( n = 51, 16%), angina pectoris ( n = 39, 13%), diabetes mellitus ( n = 31, 10%), thyroid disease ( n = 31, 10%), mild mental disorder ( n = 27, 9%), hypertension ( n = 18, 6%), cerebral infarction ( n = 17, 6%), leiomyoma ( n = 15, 5%) and anaemia ( n = 15, 5%). Roughly 10% of the patients were deficient in zinc. This study suggested that the serum concentration of zinc was most important to the patients with tongue pain. Many patients had more than one systemic condition, and all were taking various drugs.

Serum Vitamin B12 Concentrations among Mothers and Newborns and Follow-up Study to Assess Implication on the Growth Velocity and the Urinary Methylmalonic Acid Excretion

Cobalamin (B(12)) deficiency has been reported in infants born to mothers with low cobalamin intake. Early diagnosis of vitamin B(12) deficiency in infants is critical for the prevention of neurobehavioral disorders. We investigated the relationship between serum vitamin B(12) level in newborns and in their healthy mothers who consumed an omnivorous diet. Anthropometry was studied longitudinally to assess the growth velocity of the infants. Urinary methylmalonic acid (MMA) excretion of 6-month old infants was compared retrospectively as the biomarker correlated with the initial serum vitamin B(12) concentrations. Serum cobalamin and blood hemoglobin were determined in 84 pairs of newborns and their mothers. Urinary MMA excretion was measured in the same subjects during the first 6 months of the post partum period. At birth, median serum cobalamin levels were 152.0 pmol/L in the mothers and 296.6 pmol/L in the newborns. Maternal and neonatal serum cobalamin levels had no effect on growth velocity during the first six months of postnatal life. Serum maternal and neonatal cobalamin levels were inversely associated with urinary MMA excretion. Early diagnosis of vitamin B(12) status in neonates and infants is crucial, particularly in nutritionally deprived areas. Biochemical measurement of plasma cobalamin or its metabolic marker MMA is highly recommended. Urinary MMA measurement in cobalamin diagnostics provides an advantage in that blood sampling is not required. A vitamin B(12) taskforce should be created to alleviate vitamin deficiency and its negative consequences.