Red Blood Cell Folate Levels Research Articles

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Folate deficiency and aberrant DNA methylation and expression of FHIT gene were associated with cervical pathogenesis.

Aberrant DNA methylation is a recognized feature in various types of human cancer, and folate has a vital role in the epigenetics of mammalian cells by supplying methyl groups for DNA methylation reactions. Fragile histidine triad (FHIT) is a tumor suppressor gene that is frequently silenced in cervical cancer (CC) and preneoplastic lesions. Promoter hypermethylation was previously observed in CC, and its epigenetic silencing has been observed at mRNA or protein levels. Changes in folate intake to modulate DNA methylation may be a mechanistic link to cancer, but this remains to be elucidated. The aim of the present study was to evaluate the influences of folate on FHIT gene methylation and expression in the progression of cervical cancerization. In the present study, red blood cell (RBC) folate levels, FHIT gene methylation status, and mRNA and protein expression levels were detected in 254 women, including normal cervix (NC, n=80), cervical intraepithelial neoplasm grade 1 (CIN1, n=55; CIN2/3, n=55) and cervical squamous cell carcinoma (SCC, n=64) samples. The methylation status of FHIT gene and its mRNA and protein expression levels were measured in CaSki (HPV16 positive) and C33A (HPV16 negative) CC cells treated with different concentrations of folate. The results indicated that FHIT gene methylation rate increased with the severity of cervix lesions, however, RBC folate levels, FHIT mRNA and protein expression levels were reduced. The proliferation inhibition rate, apoptosis rate, and FHIT protein and mRNA expression levels increased along with rising concentrations of folate, whereas the degree of FHIT gene methylation gradually weakened in CaSki or C33A cell lines. The present findings indicated that folate deficiency, FHIT gene promoter hypermethylation and reduced expression were significantly associated with cervical carcinogenesis. The results indicated that folate was able to enhance apoptosis and inhibit the cervical cell proliferation while regulating FHIT gene methylation and expression. Adequate intake of folate to maintain normal DNA methylation status is an effective way for cervical lesions prevention, and demethylation treatment may offer a new strategy for therapy of CC.

Optimization of folic acid supplementation in the prevention of neural tube defects.

We examined the relationship between timing and duration of folic acid (FA) supplementation in achieving red blood cell (RBC) folate levels in early pregnancy which are optimal (>906 nmol/l) for the prevention of neural tube defects (NTDs). Clinical, FA supplementation and dietary folate details were computerized at the first antenatal visit. Maternal blood samples were analysed for RBC and serum folate. Of the 502 women, 98.2% (n = 493) reported taking FA. There was a positive correlation between duration of supplementation and both RBC folate (r = 0.43, P < 0.001) and serum folate (rho = 0.29, P < 0.001). The optimal RBC folate level was achieved in 80.4% (n = 46) of women who started FA 400 μg 4-8 weeks before their LMP compared with only 53.6% (n = 153) in women who started 4-8 weeks after their LMP (P < 0.001). This study provides, for the first time, information on both the timing and duration of FA that will achieve the optimum RBC folate levels associated with the prevention of NTDs. Women who are taking FA (400 μg) need to start before they conceive.

A Cross-Sectional Study of Dietary and Genetic Predictors of Blood Folate Levels in Healthy Young Adults.

Since 1998, the U.S. has mandated folic acid (FA) fortification of certain grain products to reduce the risk of neural tube defects. Folate intake and red blood cell (RBC) folate concentrations increased substantially post-intervention, although recent studies raise concerns about the level of ongoing benefit. This study investigated blood folate level determinants in healthy young adults, including intake of naturally occurring food folate, synthetic FA, and the interaction of naturally occurring food folate with a common missense variant in the FOLH1 gene thought to affect absorption. Participants (n = 265) completed the Diet History Questionnaire II, RBC folate testing, and were genotyped for the 484T>C FOLH1 variant. Men reported significantly greater intake of all folate sources except for supplemental FA, but RBC folate levels did not significantly differ by sex. Synthetic FA was a stronger predictor of RBC folate than naturally occurring food folate. In the largest racial group, synthetic FA and the interaction of FOLH1 genotype with naturally occurring food folate significantly predicted RBC folate, with the overall model accounting for 13.8% of the variance in RBC folate levels. Blood folate levels rely on a complex interaction of natural and synthetic folate intake as well as FOLH1 genotype.

Discontinuation of Folic Acid Supplementation in Young Patients With Sickle Cell Anemia.

Folic acid (FA) is commonly prescribed for patients with sickle cell anemia, but evidence for the efficacy of this practice is lacking. We stopped FA supplementation and measured red blood cell folate levels after discontinuation of FA in 72 patients with clinically severe forms of sickle cell disease. We compared hemoglobin and reticulocyte counts before and after FA discontinuation in 51 of those patients, the majority of whom were on hydroxyurea. No patients had red blood cell folate levels below normal and no significant difference in hemoglobin levels (P=0.18) or reticulocyte counts (P=0.37) was found before and after FA discontinuation.

Predictors of Hand-Foot Syndrome and Pyridoxine for Prevention of Capecitabine–Induced Hand-Foot Syndrome

ImportanceHand-foot syndrome (HFS) is a common adverse effect of capecitabine treatment.ObjectiveTo compare the incidence and time to onset of grade 2 or greater HFS in patients receiving pyridoxine vs placebo and to identify biomarkers predictive of HFS.Design, Setting, and ParticipantsThis single-center, randomized double-blind, placebo-controlled phase 3 trial conducted at National Cancer Centre Singapore assessed whether oral pyridoxine could prevent the onset of grade 2 or higher HFS in 210 patients scheduled to receive single-agent capecitabine chemotherapy for breast, colorectal, and other cancers.InterventionsPatients were randomized to receive concurrent pyridoxine (200 mg) or placebo daily for a maximum of 8 cycles of capecitabine, with stratification by sex and use in adjuvant or neoadjuvant vs palliative setting. Patients were withdrawn from the study on development of grade 2 or higher HFS or cessation of capecitabine.Main Outcomes and MeasuresPrimary end point was the incidence of grade 2 or higher HFS in patients receiving pyridoxine. Secondary end points included the time to onset (days) of grade 2 or higher HFS and identification of biomarkers predictive of HFS, including baseline folate and vitamin B12 levels, as well as genetic polymorphisms with genome-wide arrays.ResultsIn this cohort of 210 patients (median [range] age, 58 [26-82] years; 162 women) grade 2 or higher HFS occurred in 33 patients (31.4%) in the pyridoxine arm vs 39 patients (37.1%) in the placebo arm (P = .38). The median time to onset of grade 2 or higher HFS was not reached in both arms. In univariate analysis, the starting dose of capecitabine (odds ratio [OR], 1.99; 95% CI, 1.32-3.00; P = .001), serum folate levels (OR, 1.27; 95% CI, 1.10-1.47; P = .001), and red blood cell folate levels (OR, 1.25; 95% CI, 1.08-1.44; P = .003) were associated with increased risk of grade 2 or higher HFS. In multivariate analyses, serum folate (OR, 1.30; 95% CI, 1.12-1.52; P < .001) and red blood cell folate (OR, 1.28; 95% CI, 1.10-1.49; P = .001) were the only significant predictors of grade 2 or higher HFS. Grade 2 or higher HFS was associated with 300 DNA variants at genome-wide significance (P < 5 × 10−8), including a novel DPYD variant (rs75267292; P = 1.57 × 10−10), and variants in the MACF1 (rs183324967, P = 4.80 × 10−11; rs148221738, P = 5.73 × 10−10) and SPRY2 (rs117876855, P < 1.01 × 10−8; rs139544515, P = 1.30 × 10−8) genes involved in wound healing.Conclusions and RelevancePyridoxine did not significantly prevent or delay the onset of grade 2 or higher HFS. Serum and red blood cell folate levels are independent predictors of HFS.Trial Registrationclinicaltrials.gov Identifier: NCT00486213

Short interpregnancy intervals, maternal folate levels, and infants born small for gestational age: a preliminary study in a Canadian supplement-using population.

Short interpregnancy intervals (SIPI) have been associated with increased risks for adverse neonatal outcomes including preterm delivery and infants small for gestational age (SGA). It has been suggested that mechanistically, adverse neonatal outcomes after SIPI arise due to insufficient recovery of depleted maternal folate levels prior to the second pregnancy. However, empirical data are lacking regarding physiological folate levels in pregnant women with SIPI and relationships between quantified physiological folate levels and outcomes like SGA. Therefore, we sought to test 2 hypotheses, specifically that compared with controls women with SIPI would: (i) have lower red blood cell folate (RBCF) levels and (ii) be more likely to have SGA infants (defined as <10th percentile). Using data collected in British Columbia, Canada, for a larger study on perinatal psychopathology, we documented supplementation use and compared prenatal RBCF levels and proportion of SGA infants between women with SIPI (second child conceived ≤24 months after previous birth, n = 26) and matched controls (no previous pregnancies, or >24 months between pregnancies, n = 52). There were no significant differences in either mean RBCF levels (Welch's t test, p = 0.7) or proportion of SGA infants (Fisher's exact test, p = 0.7) between women with SIPI and matched controls. We report the first data about RBCF levels in the context of SIPI. If confirmed, our finding of no relationship between these variables in this population suggests that continued folic acid supplementation following an initial pregnancy mitigates folate depletion. We found no relationship between SIPI and SGA.

Hydroxytyrosol supplementation increases vitamin C levels in vivo. A human volunteer trial

Hydroxytyrosol (HT) is a main phenolic component of olive oil. In this study, we investigated the safety and effects produced by HT purified (99.5%) from olive mill waste. HT was administered at a daily dosage of 45mg for 8 weeks to volunteers with mild hyperlipidemia (n=14). We measured markers of cardiovascular disease risk, enzyme markers of several clinical conditions, hematology, antioxidant parameters, vitamins and minerals at baseline (T0), 4 weeks (T4) and 8 weeks (T8). The values obtained at T4 and T8 were compared with baseline. We found that the HT dose administered was safe and mostly did not influence markers of cardiovascular disease, blood lipids, inflammatory markers, liver or kidney functions and the electrolyte balance. Serum iron levels remained constant but a significant (P<0.05) decrease in ferritin at T4 and T8 was found. Serum folate and red blood cell folate levels were also reduced at T4 and T8. Finally, vitamin C increased by two-fold at T4 and T8 compared with levels at baseline. These results indicate a physiologically relevant antioxidant function for HT through increasing endogenous vitamin C levels.

A positive association between umbilical cord RBC folate and fetal TL at birth supports a potential for fetal reprogramming

Telomere length (TL) has been studied extensively in adults; however, limited information exists regarding maternal influences on TL in utero. The objective of this study was to investigate the relationship between fetal red blood cell (RBC) folate levels, a surrogate measure for maternal folate levels, and TL. We hypothesized that umbilical cord RBC folate concentrations would positively correlate with fetal TL. Data for this analysis were collected as part of a prospective cohort study that recruited pregnant women upon admission into labor and delivery. Cord blood was collected for 96 maternal-fetal dyads, and DNA analysis was performed using quantitative polymerase chain reaction. The telomere to single copy gene ratio method was used to determine TL, and RBC folate levels were measured. Statistical analysis was conducted by incorporating a bootstrapping approach into generalized linear modeling–based analyses. Consistent significant positive correlations were observed between RBC folate and TL (telomere to single copy gene ratio) with 9880 of the 10000 (98.8%) iterations performed having a P value less than .05. Our study shows a positive association between umbilical cord RBC folate and fetal TL at birth. These findings may provide a pathway of understanding and preventing adult-onset disease and mortality through intrauterine reprogramming.

Folate status of women in Toronto: Implications of folate fortification and supplementation.

To assess the percentage of women of childbearing age with suboptimal levels of folate for protecting against neural tube defects (&lt;906 nM), and assess folate status among the elderly. A total of 1,035 anonymous blood samples from a centralized clinical laboratory, with a catchment area across the Greater Toronto Area, were assessed for red blood cell (RBC) folate concentrations using a chemiluminescent immunoassay. Folate analysis was requested by physicians as part of clinical care. Available data included age, sex, and RBC folate concentration. Descriptive statistics were used to characterize the percent of women who had suboptimal blood folate concentrations, and a multiple regression was used to analyze determinants of folate status. Our data from 2013 show that 7% of women of childbearing age (15-45 years) had RBC folate concentrations below 906 nM, a substantially lower percentage than in our 2006 study (40%). Results from the multiple regression showed that age is a significant positive predictor of higher RBC folate status (p &lt; 0.001). Compared to our earlier data, we report a significant decrease in the suboptimal folate status among women of childbearing age. We also show that age is a predictor of higher RBC folate levels. Our data are limited due to a lack of information regarding patient or physician characteristics, and to the nature of our sample, yet our results are consistent with the continued increase in folate status observed among several population-level studies in the US and Canada post-fortification. Further research is needed to determine the reasons for and future implications of this continued increase in the elderly.

Periconception Maternal Folate Status and Human Embryonic Cerebellum Growth Trajectories: The Rotterdam Predict Study.

We aimed to investigate whether periconceptional maternal folate status affects human embryonic cerebellar size and growth trajectories. In a prospective periconceptional cohort participants filled out questionnaires and received weekly transvaginal 3D-ultrasounds between 7+0 and 12+6 weeks gestational age (GA). Viable non-malformed singleton pregnancies were selected for cerebellar measurements; transcerebellar diameter, (TCD), left and right cerebellar diameters (LCD, RCD). Linear mixed models were performed to estimate associations between questionnaire data on the timing of maternal folic acid supplement initiation and longitudinal cerebellar measurements as a function of crown-rump length (CRL) and GA. Maternal red blood cell folate concentrations were analysed before 8 weeks GA to validate the associations. A total of 263 serial high quality three-dimensional ultrasound scans of 135 pregnancies were studied. Preconceptional compared to postconceptional initiation of folic acid use was associated with slightly larger cerebellar diameters per millimetre increase of CRL (TCD: β = 0.260mm, 95%CI = 0.023–0.491, p<0.05; LCD: β = 0.171mm, 95%CI = 0.038–0.305, p<0.05; RCD: β = 0.156mm, 95%CI = 0.032–0.280, p<0.05) and with proportional cerebellar growth (TCD/CRL:β = 0.015mm/mm, 95%CI = 0.005–0.024, p<0.01; LCD/CRL:β = 0.012mm/mm, 95%CI = 0.005–0.018, p<0.01; RCD/CRL:β = 0.011mm/mm, 95%CI = 0.005–0.017, p<0.01). Cerebellar growth was significantly highest in the third quartile of maternal red blood cell folate levels (1538–1813 nmol/L). These first findings show that periconceptional maternal folate status is associated with human embryonic cerebellar development. Implications of these small but significant variations for fetal cerebellar growth trajectories and the child’s neurodevelopmental outcome are yet unknown and warrant further investigation.

High red blood cell folate is associated with an increased risk of death among adults with diabetes, a 15-year follow-up of a national cohort

Background and aimTo describe the mortality and fatality of diabetes and assess their relationship with the level of red blood cell (RBC) folate. Methods and resultWe analyzed the data of 526 adults with diabetes who participated in the National Health and Nutrition Examination Survey (1991–1994) as the baseline examination, and were followed up through December 31, 2006. Estimates of the hazard ratios (HRs) of selected death causes for individuals with different levels of RBC folate were obtained from Cox proportional hazards regression. A total of 295 deaths were recorded by the end of a 15-year follow-up with a mortality rate of 58.48 per 1000 person year (py). Diabetes was listed as a contributing cause for 136 deaths, accounting for 46.1% of the total deaths with a fatality rate 26.96 per 1000 py. Mortality rate for all-cause in the group with upper quartile of RBC folate was almost twice as high as that among the group with lower quartile, 82.75 vs. 44.10 per 1000 py. After adjusting for covariates, including serum concentration of vitamin B12, cotinine, homocysteine and the history of cardio-cerebral vascular diseases assessed at the baseline, the HRs for dying from any causes were 1.00 (reference), 1.82 (95% CI = 1.25–2.66) and 2.10 (1.37–3.20) among diabetic adults with lower, intermediate, and upper quartiles of RBC folate. ConclusionDiabetes was listed as a contributing cause for less than half of the deaths among adults with diabetes after 15+ years of follow-up; high RBC folate concentration was associated with an elevated risk of death among adults with diabetes.

Association of maternal homocysteine and vitamins status with the risk of neural tube defects in Tunisia: A case-control study.

This study was conducted to determine whether low folate and vitamin B12 levels, as well as high homocysteine levels in pregnant women are associated with neural tube defects (NTDs) in Tunisia. A total of 75 NTDs pregnancies and 75 matched controls were included in the study. Their vitamin B12, folate, and red blood cell folate concentrations were measured using a radio-immunoassay kit and total homocysteine concentrations were determined using a fluorescent polarization immunoassay. Vitamin B12 and folate concentrations were lower in NTD-affected pregnant women than in controls (respectively, p = 0.009 and p < 0.001). Total homocysteine concentration was significantly higher in the NTDs group than in controls (p = 0.008). In the case group, the folate levels were positively related with vitamin B12 levels (r = 0.54; p < 0.001) and negatively correlated with total homocysteine levels (r = -0.19; p = 0.04). Besides, red blood cell folate levels were positively correlated with folate levels (r = 0.24; p = 0.02) and negatively correlated with total homocysteine levels (r = -0.37; p = 0.001). Lower concentrations of folate and vitamin B12 are related to the increased risk of NTDs. Both folate and vitamin B12 intake insufficiency could contribute to the increased risk of NTDs. A dietary supplement, combining folate and vitamin B12, might be an effective measure to decrease the NTDs incidence in Tunisia.

Vitamin B12 and folate levels in healthy Swiss senior citizens: a prospective study evaluating reference intervals and decision limits.

BackgroundThe vitamin B12 and folate status in nonanaemic healthy older persons needs attention the more so as decrease in levels may be anticipated from reduced haematinic provision and/or impaired intestinal uptake.MethodsA total of 1143 subjectively healthy Swiss midlands participants (637 females and 506 males), ≥60 years of age were included in this study. Levels of vitamin B12, holotranscobalamin (holoTC), methylmalonic acid (MMA), homocysteine (Hcy), serum folate, red blood cell (RBC) folate were measured. Further, Fedosov’s wellness score was determined. Associations of age, gender, and cystatin C/creatinine-based estimated kidney function, with the investigated parameters were assessed. Reference intervals were calculated. Further, ROC analysis was done to assess accuracy of the individual parameters in recognizing a deficient vitamin B12 status. Finally, decision limits for sensitive, specific and optimal recognition of vitamin B12 status with individual parameters were derived.ResultsThree age groups: 60–69, 70–79 and ≥ 80 had median B12 (pmol/L) levels of 237, 228 and 231 respectively (p = 0.22), holoTC (pmol/L) of 52, 546 and 52 (p = 0.60) but Hcy (μmol/L) 12, 15 and 16 (p < 0.001), MMA (nmol/L) 207, 221 and 244 (p < 0.001). Hcy and MMA (both p < 0.001), but not holoTC (p = 0.12) and vitamin B12 (p = 0.44) were found to be affected by kidney function. In a linear regression model Fedosov’s wellness score was independently associated with kidney function (p < 0.001) but not with age. Total serum folate and red blood cell (RBC) folate drift apart with increasing age: whereas the former decreases (p = 0.01) RBC folate remains in the same bandwidth across all age groups (p = 0.12) A common reference interval combining age and gender strata can be obtained for vitamin B12 and holoTC, whereas a more differentiated approach seems warranted for serum folate and RBC folate.ConclusionWhereas the vitamin B12 and holoTC levels remain steady after 60 years of age, we observed a significant increment in MMA levels accompanied by increments in Hcy; this is better explained by age-related reduced kidney function than by vitamin B12 insufficiency. Total serum folate levels but not RBC folate levels decreased with progressing age.Electronic supplementary materialThe online version of this article (doi:10.1186/s12877-015-0060-x) contains supplementary material, which is available to authorized users.

Association of methylenetetrahydrofolate reductase gene polymorphisms with polycystic ovary syndrome

To assess the association of C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene with the susceptibility to polycystic ovary syndrome (PCOS). Blood samples of 115 PCOS patients and 58 fertile women (for whom PCOS has been excluded) were collected for DNA extraction. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for determining the C677T and A1298C polymorphisms. A database has been set up with Epidata and a significance test was performed with a statistical analysis system. A significant difference has been found in the allele frequencies of MTHFR gene 677 C and T polymorphisms between the two groups (P<0.01), for which T allele has increased the risk for PCOS by 2.06 times. Heterozygous and homozygous genotypes at position 677 (CT and TT) were more common among PCOS cases than controls, with an OR of 3.91 (95%CI: 1.70-8.97) and 4.39 (95%CI: 1.77-10.89), respectively. There was no statistical difference in genotypic distribution of MTHFR gene A1298C polymorphism (P>0.05). In the PCOS group, there was a significant difference with an OR of 6.40 (95%CI: 1.71-23.95) for an increased risk of insulin resistance in homozygous C677T mutations (TT) compared with the wild genotype (CC, P<0.01). The PCOS group and the control group also differed significantly in their red blood cell folate levels (P<0.01), but not in serum vitamin B12 and homocysteine levels (P>0.05). MTHFR gene C677T polymorphism is associated with PCOS, for which CT and TT genotypes can increase the risk of PCOS. The TT genotype can also increase the risk of insulin resistance in PCOS patients. The A1298C polymorphism of the MTHFR gene is not associated with the occurrence of PCOS. The folate level in red blood cells of PCOS patients is lower, for whom folate should be supplemented.

Pre-conception Folic Acid and Multivitamin Supplementation for the Primary and Secondary Prevention of Neural Tube Defects and Other Folic Acid-Sensitive Congenital Anomalies.

Abstract Objective To provide updated information on the pre- and post-conception use of oral folic acid with or without a multivitamin/micronutrient supplement for the prevention of neural tube defects and other congenital anomalies This will help physicians, midwives, nurses, and other health care workers to assist in the education of women about the proper use and dosage of folic acid/multivitamin supplementation before and during pregnancy. Evidence Published literature was retrieved through searches of PubMed, Medline, CINAHL, and the Cochrane Library in January 2011 using appropriate controlled vocabulary and key words (e.g., folic acid, prenatal multivitamins, folate sensitive birth defects, congenital anomaly risk reduction, pre-conception counselling). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies published in English from 1985 and June 2014. Searches were updated on a regular basis and incorporated in the guideline to June 2014 Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies Costs, risks, and benefits The financial costs are those of daily vitamin supplementation and eating a healthy folate-enriched diet. The risks are of a reported association of dietary folic acid supplementation with fetal epigenetic modifications and with an increased likelihood of a twin pregnancy These associations may require consideration before initiating folic acid supplementation The benefit of folic acid oral supplementation or dietary folate intake combined with a multivitamin/micronutrient supplement is an associated decrease in neural tube defects and perhaps in other specific birth defects and obstetrical complications. Values The quality of evidence in the document was rated using the criteria described in the Report of the Canadian Task Force on Preventative Health Care (Table 1).

Maternal predictors of RBC folate levels in an urban Canadian population.

To assess factors associated with low Red Blood Cell folate (RBCf) levels in an obstetric population in a tertiary centre. Cross-sectional study. Three hundred and fifty women completed a questionnaire detailing use of folic acid supplementation, and had their RBCf levels measured. Values ≥ 906 nmol/L were considered optimal. Factors associated with optimal RBCf were assessed, individually and in a logistic regression model. Median RBCf was 1282 nmol/L. Thirty-five women (10%) had suboptimal levels. Predictors of suboptimal RBCf were non-Caucasian ethnicity, non-consumption of folic acid supplementations, and inadequate health care provider information regarding the benefits of folic acid consumption. Although, in our population, a high proportion of women achieved optimal levels of RBCf, some women remain at risk due to inadequate folate consumption. Patient and health care provider education regarding folate can still be improved, particularly in the groups identified to be at greater risk.

Associations between Folate Biomarker Levels and Renal Function among Adults in the U.S.

Since the kidneys are highly involved in maintaining folate homeostasis, the effect of folic acid fortification of grain products may be affected by reduced kidney function. However, it is unclear what the impact of renal insufficiency is on folate status. This study investigated the associations of renal function with levels of serum and red blood cell (RBC) folate, plasma homocysteine and the presence of serum unmetabolized folic acid (UMFA) in U.S. adults. Data of participants of the National Health and Nutrition Examination Survey (NHANES) 1999–2002 aged 蠅 40 years were used in this study. Associations between levels of folate biomarkers and homocysteine and the presence of UMFA and three estimated glomerular filtration rate (eGFR) categories (&lt; 60, 60–90 and 蠅 90 mL/min/1.73 m2) were assessed using multivariable regression models, controlled for confounders. The Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) formula was used to estimate eGFR. In men and women, RBC folate and plasma homocysteine levels were significantly higher among individuals with eGFR &lt; 60 ml/min/1.73 m2 compared with those with eGFR 蠅 90 ml/min/1.73 m2; serum folate levels were not significantly different between eGFR groups. In women but not in men, UMFA was significantly more likely to appear in the blood of individuals with eGFR &lt; 60 ml/min/1.73 m2 than those with GFR 蠅 90 ml/min/1.73 m2 (OR: 2.2, 95% CI: 1.2–4.0). Reduced renal function may be implicated in the increased blood folate concentrations. Caution should be taken in consumption of folic acid‐enriched foods and supplements among individuals with renal insufficiency.

Impact of asphyxia on red blood cell folate concentration levels in newborns.

To determine whether red blood cell (RBC) folate concentration levels are correlated with the occurrence of neonatal asphyxia and to study the effects of gestational age, gender, and mode of delivery on RBC folate concentration levels in newborns. Asphyxia is one of the frequent causes of morbidity and mortality of newborns. Severe perinatal asphyxia can arise due to many factors. In a prospective study, the RBC folate concentrations were determined on day 1 of life in the whole group (n=181) of full-term (n=121) and preterm (n=60) newborns. Immunochemical analysis for the determination of folate in erythrocytes was performed. RBC folate concentration levels in asphyxiated newborns (n=16) were significantly decreased (median 974 ng/ml; p=0.023) in comparison with healthy newborns. On the other hand, the RBC folate concentration levels were significantly increased in preterm newborns (median 1,212 ng/ml; p=0.01) in comparison with full-term newborns (median 1,098 ng/ml). Higher RBC folate concentration levels were found in newborns which had been delivered by Caesarean section (median 1,188 ng/ml; p=0.02) compared to those born vaginally (median 1,098 ng/ml). Our results confirmed a significant decrease in RBC folate concentration in asphyxiated newborns on their first day of life (Fig. 4, Ref. 36).

Amount of folic acid in different types of nutrition used in the neonatal period.

Folic acid is one of the important supplements for adequate development during pregnancy. A higher intake of folic acid during pregnancy and lactation is recommended. In prospective study the group of premature newborns (n = 52) and the type of nutrition were observed. The red blood cell (RBC) folate concentration levels were determined in the first 24 hours after delivery, before and after oral treatment with folic acid (100 µg/day). Immunochemical analysis for the determination of folate in erythrocytes was performed. In the group of premature newborns the RBC folate concentration levels after treatment were significantly increased (p < 0.0001). A dynamic increase in the concentration levels of folates in erythrocytes before and after treatment was observed, in spite of the reciprocally decreasing blood count parameters, but without any statistically significant correlation. The infant nutrition before treatment contained significantly higher amount of folic acid in fortified breast milk compared to breast milk (p = 0.04). The various types of nutrition for preterm newborns contain a different amount of folic acid. It poses a question of real needs of these patients. The best way to determine the optimal whole amount of folate is to know the real levels of folate in premature newborns (Tab. 2, Fig. 5, Ref. 26). Text in PDF www.elis.sk.