Interaction of serum vitamin B12 and folate with MTHFR genotypes on risk of ischemic stroke

Associations between folate intake, serum folate, and stroke risk: The mediating role of dietary inflammatory index from NHANES 2007-2018

BACKGROUND

This study investigates the relationships between folate intake, RBC folate, serum folate levels, and stroke risk, with an emphasis on the mediating roles of the dietary inflammatory index (DII) and systemic immune-inflammation index (SII).

METHODS

A cross-sectional analysis was conducted using 24,106 participants from NHANES (2007-2018). Associations were assessed with weighted multivariate logistic regression, adjusting for key confounders. Propensity score matching (PSM) was applied, yielding 1,838 matched participants, respectively. Nonlinear relationships were analyzed with restricted cubic splines, and mediation analysis was performed for DII and SII.

RESULTS

Post-PSM, folate intake in Q2 (252-350 μg/day), Q3 (350-484 μg/day), and Q4 (> 484 μg/day) was significantly inversely associated with stroke risk (trend P < 0.05), with adjusted ORs of 0.62 (95 % CI: 0.45-0.85), 0.65 (95 % CI: 0.46-0.90), and 0.60 (95 % CI: 0.42-0.86), respectively. Serum folate levels in Q3 (37.0 - 54.8 nmol/L) were also protective (OR: 0.47, 95 % CI: 0.32-0.68, trend P < 0.05). Serum folate levels exhibited a biphasic effect, with the lowest stroke risk at 41.9 nmol/L before PSM and 43.3 nmol/L after PSM. Mediation analysis showed DII mediated 45.2 % of the relationship between folate intake and stroke risk (P = 0.018), while SII's mediation effect was minimal (0.412 %, P = 0.016). No significant interactions were observed between folate intake, serum folate and stratified variables (P > 0.05) after PSM.

CONCLUSION

Higher folate intake lowers stroke risk, with DII playing a significant mediating role, while serum folate presents a biphasic risk pattern. Personalized dietary strategies addressing folate intake and inflammation may be crucial for stroke prevention.

Association of MTHFR C677T, MTHFRA1298C, and MTRRA66G Gene Polymorphisms with Hyperhomocysteinemia and Its Modulation by the Combined Effect of Vitamin B12 and Folate in Chinese Population with Hypertension

BACKGROUND

In China, the MTHFR 677T allele, unlike in most Western populations, is a rare genetic variant linked to various disorders. The contributing nutritional and genetic factors to this genetic risk remain unclear.

OBJECTIVE

This study aimed to elucidate the interactions between genetic variations in total homocysteine (tHcy) pathway genes, serum tHcy concentrations, and nutritional factors in a Chinese population with hypertension.

METHODS

This study analyzed 1304 Chinese adults with hypertension aged ≥18 y enrolled in the China Precision Nutrition and Health KAP Real World Study (CPNAS). Serum concentrations of vitamin B12 and folate were measured using the magnetic microparticle chemiluminescence method, and tHcy concentrations were measured using Hcy Assay kits. Identification of the MTHFR C677T, MTHFR A1298C, and MTRR A66G polymorphisms was performed via time-of-flight nucleic spectrometry.

RESULTS

Our findings revealed significant sex differences in tHcy concentrations, with males exhibiting higher tHcy concentrations than females (13.95 μmol/L vs. 11.15 μmol/L, P < 0.001). Individuals deficient in both vitamin B12 and folate had an increased risk of hyperhomocysteinemia (H-Hcy) (57.4%). In contrast, the prevalence of H-Hcy was lower among those deficient in either vitamin B12 (31.1%) or folate (23.2%) alone. Significant associations were identified between the MTHFR C677T and A1298C polymorphisms and elevated serum tHcy concentrations, particularly in individuals homozygous for the T allele. Conversely, the MTRR A66G genotype did not show a significant correlation with tHcy concentrations. Optimal vitamin B12 concentrations significantly modulated the genotypic effect on tHcy concentrations, with individuals having adequate vitamin B12 and folate exhibiting low tHcy concentrations, even among high-risk genotypes (TT).

CONCLUSIONS

Adequate concentrations of folate and vitamin B12 significantly reduce serum tHcy concentrations and mitigate the genotypic impact on tHcy concentrations, highlighting the potential for targeted nutritional interventions to manage cardiovascular risks associated with H-Hcy. This trial was registered at clinicaltrials.gov as ChiCTR2100051983.

Association Between Serum Folate Concentrations and 10-Year Stroke Risk in a Prospective Community Cohort: Mediation and Interaction Analyses

The relationship between folate concentrations and stroke risk remains unestablished, and the mediation effect of homocysteine (Hcy) and interaction effect of methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism has yet to be investigated. This cohort study involved 4903 subjects derived from a Chinese community population. The association between folate and first stroke was examined in Cox proportional hazard regression models. The mediation analyses involving Hcy and the undiscovered modification of the MTHFR C677T genotype were assessed. The mean (SD) age of subjects was 56.7 (8.8) years old, and 37.0% were male. A total of 407 strokes, 375 ischemic strokes and 47 hemorrhagic strokes occurred during the mean (SD) follow-up of 9.3 (1.8) years. The participants in the highest folate quartile (≥8.2 ng/mL) exhibited a lower stroke risk compared to those in the lowest quartile (hazard ratio [HR]: 0.68, 95% confidence interval [CI]: 0.50-0.93, p = 0.017; p for trend = 0.009). Hcy significantly mediated 14.51% of the relationship between folate and stroke in the fully adjusted model. Only in individuals with the MTHFR 677CC genotype but not CT/TT genotype was folate adversely correlated with stroke (HR: 0.88, 95% CI: 0.79-0.97, p for interaction = 0.026) and ischemic stroke (HR: 0.88, 95% CI: 0.80-0.98, p for interaction = 0.035). Insufficient folate concentrations were associated with a heightened 10-year stroke risk, in which Hcy concentrations played a crucial mediating role. MTHFR C677T gene polymorphism could potentially modify the folate-stroke relationship.

Association between serum folate and sleep duration in American adults: A cross-sectional analysis of the National Health and Nutrition Examination Survey 2005 to 2010

Folate is a vitamin that is exclusively derived from diet sources. Low folate levels are typically associated with cardiovascular disease, cognitive impairment, and cancer risk. However, few studies have examined the direct relationship between serum folate levels and sleep duration. Accordingly, we aimed to examine the relationship between serum folate levels and sleep duration. Using data from the National Health and Nutrition Examination Survey (NHANES), we examined the association between serum folate levels and sleep duration. We used laboratory data to obtain independent serum folate, and covariate data, including total cholesterol, high-density lipoprotein, blood glucose, and glycated hemoglobin; dependent variable sleep duration and covariate data including race, family income, marital status, education, and country of birth from questionnaire data; and other covariate data such as systolic blood pressure, diastolic blood pressure, waist circumference, and body mass index data from the measured data. Data was primarily analyzed using multiple regression analysis, stratified analysis with interactions, restricted cubic splines (RCS), and threshold effect analysis. A total of 14,072 participants over 19 years of age were enrolled, comprising 6923 (49.2%) males and 7149 (50.8%) females, with a median age of 48 years. The association between serum folate levels and sleep duration exhibited an inverted L-shaped curve (P = .033) in RCS. In the threshold analysis, for participants with serum folate of <32.208 nmol/L (β = 0.608, 95% CI: (0.275, 0.942), P < .001), the sleep duration was significantly increased by 0.608 minutes, with every 1 nmol/L in serum folate increased. At serum folate of ≥32.208 nmol/L, no significant association between serum folate and sleep duration was detected [β = 5.686, 95% CI: (-1.508, 12.88), P = .118]. Our findings revealed an inverted L-shaped relationship and saturation effects between serum folate levels and sleep duration in adults in the United States.

Association of Vitamin B12 and Polymorphism of TCN2 with Early-Onset Post-Stroke Depression

BACKGROUND

Post-stroke depression (PSD) is a common neuropsychiatric complication after a stroke with complex mechanisms. However, few studies have identified the role of vitamin B12 and folate in the occurrence and pathophysiology of PSD. The aim of our study is to investigate the relationship among vitamin B12, folate, their transporter genes, and early-onset PSD.

METHOD AND MATERIAL

A total of 173 ischemic stroke patients were recruited in Xiangya Hospital of Central South University. We collected peripheral blood samples, clinical data, and demographics at admission. The 17-item Hamilton Depression Scale was used for screening for the existence of depression at 2 weeks after stroke onset. Serum vitamin B12 and folate level were measured based on double-antibody sandwich enzyme-linked immune-sorbent assay. Four single nucleotide polymorphisms (SNP) of transcobalamin 2 (TCN2) and solute carrier family 19 member 1 were genotyped using SNPscanTM multiplex SNP typing Kit.

RESULTS

Eighty-four patients were diagnosed with PSD at 2 weeks after stroke onset, and the incidence rate was 48.6%. Serum vitamin B12 level in PSD group was significantly lower than those in the non-PSD group (p=0.018). Binary logistic regression revealed that TCN2 rs1801198 GG genotype and G allele were associated with an increased risk of PSD after adjustment for confounding factors (for GG genotype, OR = 4.253, 95% CI = 1.711~10.572, p = 0.002; for G allele, OR = 2.134, 95% CI = 1.362~3.343, p = 0.001). Moreover, individuals with the rs1801198 G allele in the PSD group exhibited lower vitamin B12 level than those with the rs1801198 G allele in the non-PSD group (p=0.045).

CONCLUSION

TCN2 rs1801198 and vitamin B12 are associated with the risk of early-onset PSD, and they may be involved in the development of PSD. Our study presents a novel standpoint for the treatment of PSD and gains insights into the mechanistic underpinnings of PSD.

Synergistic effect of folate and MTHFR C677T on hippocampal subfields and perfusion in Alzheimer's disease

BACKGROUND

Low folate intake and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism have been suggested to increase the risk of Alzheimer's disease (AD). However, the synergistic effects and their impact on brain structure and perfusion remain unclear.

METHODS

This study explored the effects of dietary and genetic deficiencies in folate metabolism on the volume of the hippocampal subregions, cerebral perfusion, and cognitive decline in 71 cognitively unimpaired (CU) individuals and 102 patients with mild cognitive impairment (MCI) due to AD or AD. All participants underwent magnetic resonance imaging, laboratory examinations, and neuropsychological assessments. The hippocampal subfields were segmented using Freesurfer, and arterial spin labeling was used to measure the cerebral blood flow.

RESULTS

We found a significant group-by-MTHFR interaction effect on folate. Patients with AD and the 677 T allele showed hypoperfusion in the left precuneus compared to patients without this mutation, which mediated the relationship between low folate level and cognitive decline in patients carrying the 677 T allele. Moreover, a synergistic effect was observed for the combination of decreased folate concentrations and the presence of the MTHFR 677 T allele on the atrophy of specific hippocampal subregions in patients with AD.

CONCLUSIONS

In addition to offering insights into the neuronal mechanism underlying gene-dependent folate-induced cognitive impairment in AD, these findings may have clinical significance for the allocation of auxiliary folate supplementation therapy in patients with AD with low folate levels and carrying the MTHFR 677 T allele and may eventually promote the selection of early individualized AD drug therapy.

Homocysteine, hyperhomocysteinemia, and H-type hypertension

Homocysteine (Hcy) is a sulphur-containing nonessential amino acid derived from the intermediate metabolites of methionine. Methionine is obtained from dietary proteins, such as poultry, meat, eggs, seafood, and dairy products. Abnormalities in Hcy metabolic pathways, deficiencies in dietary methionine, folate, and vitamins B12, B6, and B2 and genetic defects, polymorphisms, or mutations in Hcy metabolism-related enzymes may lead to an increase in plasma Hcy levels. Generally, a plasma Hcy level higher than 10 or 15 μmol/L has been defined as hyperhomocysteinemia (HHcy). An individual with essential hypertension complicated with HHcy is considered to have H-type hypertension (HTH). Currently, HHcy is considered a novel independent risk factor for various cardiovascular diseases. To provide a useful reference for clinicians, the research progress on Hcy, HHcy, and HTH in recent years was systematically reviewed here, with a focus on the source and metabolic pathways of Hcy, plasma Hcy levels and influencing factors, detection methods for plasma Hcy levels, relationship between Hcy concentration and hypertension, pathogenesis of HTH, cardiovascular complications of HTH, and treatment of HTH.

Relationship between homocysteine, vitamin B9, vitamin B12 levels methylenetetrahydrofolate reductase (C677T, A1298C) polymorphisms, and cryptogenic stroke in Tunisian adults´ patients: a case-control study

Introduction

the relationship between elevated plasma homocysteine (Hcy) and stroke has been established, but this association remains indistinct in cryptogenic stroke in adults. Our aim is to investigate the association between homocysteine, vitamins B9 and B12, and cryptogenic stroke. Furthermore, to determine the correlation between methylenetetrahydrofolate reductase (MTHFR) polymorphism and biochemical levels in plasma.

Methods

we conducted a retrospective case-control study including 100 cryptogenic stroke patients aged 18-50 years and 100 participants with age-and-sex-matched healthy controls. Clinical, radiological, and outcome data from cerebral venous thrombosis (CVT) patients were recorded. Homocysteine, vitamin B9, and vitamin B12 were analyzed. Deoxyribonucleic acids (DNAs) from both groups were tested. MTHFR C677T mutation was assessed by restriction fragment length polymorphism (PCR). All analyses were performed using Statistical Package for the Social Sciences (SPSSV.20) software. Multivariable logistic regression analysis was performed to identify factors associated with stroke risk and clinical outcomes.

Results

a total of 200 cases were included in this study, 50% (n=100) patients with cryptogenic stroke (mean age of 40.49 ± 6.2 years, sex-ratio= 1.5) and 50% (n=100) healthy cases (mean age of 39.09 ± 5.8 years, sex-ratio= 1.5). The elevated plasma level of Hcy and vitamin B9 levels deficiency increase the risk of cryptogenic stroke occurrence (aOR: 2.5; 95% (0.71-5.25), P=0.01), (aOR: 3.1; 95% (1.6-9.6), p=0.02 respectively). Additionally, vitamin B9 deficiency was significantly associated with elevated Hcy levels (4.57 ± 3.59; p=0.001). Genetic analysis revealed a significant association between homozygous TT genotype of the MTHFR C677T polymorphism, elevated Hcy levels (20.4 ± 7.07; p=0.001) and vitamin B9 deficiency (4.9±3.9; p=0.001). Furthermore, the combined CT/AC genotype was associated with elevated Hcy level (21.6 ± 9.6; p=0.001) and vitamin B9 deficiency (2.9 ± 1.0; p=0.04).

Conclusion

the presence of homozygote MTHFR C677T or dual heterozygous MTHFR C66T and A1298C, which leads to elevated Hcy and deficiency of vitamin B9 plasma levels, is correlated with an increased risk of cryptogenic stroke occurrence among adult Tunisian patients.

Serum levels of vitamin B12 combined with folate and plasma total homocysteine predict ischemic stroke disease: a retrospective case-control study

PURPOSE

This study aimed to identify and quantify the association and investigate whether serum vitamin B12 alone or vitamin B12 combined with folate and plasma total homocysteine (tHcy) levels could be used to predict the risk of acute ischemic stroke.

MATERIALS AND METHODS

This retrospective case-control study was conducted in the Department of Neurology, First Affiliated Hospital of Chongqing Medical University. It included 259 inpatients experiencing their first-ever acute ischemic stroke and 259 age-matched, sex-matched healthy controls. Patients were categorized into groups based on the etiology of their stroke: large-artery atherosclerosis (LAAS, n = 126), cardio embolism (CEI, n = 35), small vessel disease (SVD, n = 89), stroke of other determined etiology (ODE, n = 5), and stroke of undetermined etiology (UDE, n = 4). The associations of serum vitamin B12, folate, and plasma tHcy levels with the risk of ischemic stroke were evaluated using multivariable logistic regression analysis. Receiver operator characteristic (ROC) curves were used to assess the diagnostic power of vitamin B12, folate, and tHcy levels for ischemic stroke.

RESULTS

Serum vitamin B12 and folate levels were significantly lower in ischemic stroke patients compared to controls, while plasma tHcy levels were significantly higher. The first quartile of serum vitamin B12 levels was significantly associated with an increased risk of LAAS (aOR = 2.289, 95% CI = 1.098-4.770), SVD (aOR = 4.471, 95% CI = 1.110-4.945) and overall ischemic stroke (aOR = 3.216, 95% CI = 1.733-5.966). Similarly, the first quartile of serum folate levels was associated with an increased risk of LAAS (aOR = 3.480, 95% CI = 1.954-6.449), CEI (aOR = 2.809, 95% CI = 1.073-4.991), SVD (aOR = 5.376, 95% CI = 1.708-6.924), and overall ischemic stroke (aOR = 3.381, 95% CI = 1.535-7.449). The fourth quartile of tHcy levels was also significantly associated with an increased risk of LAAS (aOR = 2.946, 95% CI = 1.008-5.148), CEI (aOR = 2.212, 95% CI = 1.247-5.946), SVD (aOR = 2.957, 95% CI = 1.324-6.054), and overall ischemic stroke (aOR = 2.233, 95% CI = 1.586-4.592). For predicting different types of ischemic stroke, vitamin B12 alone demonstrated the best diagnostic value for SVD, evidenced by a sensitivity of 71.0% and negative predictive value of 90.3%, along with the highest positive likelihood ratio (+ LR) for SVD. Vitamin B12 + tHcy + folate are valuable in predicting different types of ischemic stroke, with the most significant effect observed in SVD, followed by LAAS, and the weakest predictive effect in CEI. Additionally, vitamin B12 alone in combination with other indicators, such as folate alone, tHcy alone, and folate + tHcy could reduce negative likelihood ratio (-LR) and improve + LR.

CONCLUSIONS

Vitamin B12 was an independent risk factor for acute ischemic stroke. The risk calculation model constructed with vitamin B12 + tHcy + folate had the greatest diagnostic value for SVD.

Folic acid supplementation for stroke prevention: A systematic review and meta-analysis of 21 randomized clinical trials worldwide

BACKGROUND & AIMS

The AHA/ASA guidelines for primary stroke prevention are almost a decade old. The current recommendation regarding folic acid supplementation is based on only 8 clinical trials, and an additional 13 folate trials have been published since then. This meta-analysis aims to fill in critical evidence gaps by comprehensively evaluating 21 published trials with particular attention given to identifying the true influences through stratification.

METHODS

PubMed, the Cochrane Central Register of Controlled Trials, and Embase were searched from inception to April 4, 2023. This study included all randomized controlled trials (RCTs) of folic acid with stroke as one of the reporting endpoints. Relative risks and 95% confidence intervals were used to assess the association between folic acid supplementation and the risk of stroke in a random-effects model.

RESULTS

Results from the 21 pooled RCTs totaling 115,559 participants showed that folic acid supplementation significantly reduced the risk of stroke by 10% (RR 0.90, 95%CI 0.83 to 0.98). Subgroup analyses showed that folic acid efficacy was greater in areas without fortified grain or with partially-fortified grain (RR = 0.83, 95% CI 0.75 to 0.93; RR = 1.04 in areas with grain fortification, P-interaction = 0.003). In this group, folic acid supplementation was most efficacious in those without a history of stroke or myocardial infarction (RR = 0.77, 95% CI 0.68 to 0.86; RR = 0.94 for participants with a history of stroke or myocardial infarction, P-interaction = 0.008). The efficacy of folic acid remained consistent regardless of baseline folate levels, folic acid dosage, baseline vitamin B12 levels, vitamin B12 dosage, homocysteine reduction, intervention duration, and whether folic acid was taken alone or in combination (all P-interaction>0.05). All 21 trials were free of attrition bias and reporting bias, and there was no significant publication bias.

CONCLUSIONS

This is by far the largest meta-analysis of RCTs regarding folic acid supplementation and stroke, demonstrating the overall benefit of folic acid for stroke prevention. Grain fortification and history of stroke or myocardial infarction may be the most important influences on the efficacy of folic acid for stroke prevention.

Higher homocysteine and fibrinogen are associated with early-onset post-stroke depression in patients with acute ischemic stroke

Background

Post-stroke depression (PSD) is a well-established psychiatric complication following stroke. Nevertheless, the relationship between early-onset PSD and homocysteine (Hcy) or fibrinogen remains uncertain.

Methods

Acute ischemic stroke (AIS) patients who met the established criteria were enrolled in this study. Early-onset PSD was diagnosed two weeks after the stroke. The severity of depressive symptoms was assessed by the Hamilton Depression Scale-17 items (HAMD-17), with patients scored ≥7 assigned to the early-onset PSD group. Spearman rank correlation analysis was employed to evaluate the associations between Hcy, fibrinogen, and HAMD scores across all patients. Logistic regression analysis was conducted to investigate the relationship between Hcy, fibrinogen, and early-onset PSD. Receiver operating characteristic curve (ROC) analysis was ASSDalso performed to detect the predictive ability of Hcy and fibrinogen for early-onset PSD.

Results

Among the 380 recruited patients, a total of 106 (27.89%) patients were diagnosed with early-onset PSD. The univariate analysis suggested that patients in the PSD group had a higher admission National Institutes of Health Stroke Scale (NIHSS) score, modified Rankin Scale score (mRS), Hcy, and fibrinogen levels than patients in the non-PSD group (P<0.05). The logistic regression model indicated that Hcy (odds ratio [OR], 1.344; 95% confidence interval [CI] 1.209-1.494, P<0.001) and fibrinogen (OR, 1.57 6; 95% CI 1.302-1.985, P<0.001) were independently related to early-onset PSD. Area under curve (AUC) of Hcy, fibrinogen, and Hcy combined fibrinogen to predict early-onset PSD was 0.754, 0.698, and 0.803, respectively.

Conclusion

This study indicates that Hcy and fibrinogen may be independent risk factors for early-onset PSD and can be used as predictive indicators for early-onset PSD.

Assessment of the impact of a personalised nutrition intervention in impaired glucose regulation over 26 weeks: a randomised controlled trial

Dietary interventions can reduce progression to type 2 diabetes mellitus (T2DM) in people with non-diabetic hyperglycaemia. In this study we aimed to determine the impact of a DNA-personalised nutrition intervention in people with non-diabetic hyperglycaemia over 26 weeks. ASPIRE-DNA was a pilot study. Participants were randomised into three arms to receive either (i) Control arm: standard care (NICE guidelines) (n = 51), (ii) Intervention arm: DNA-personalised dietary advice (n = 50), or (iii) Exploratory arm: DNA-personalised dietary advice via a self-guided app and wearable device (n = 46). The primary outcome was the difference in fasting plasma glucose (FPG) between the Control and Intervention arms after 6 weeks. 180 people were recruited, of whom 148 people were randomised, mean age of 59 years (SD = 11), 69% of whom were female. There was no significant difference in the FPG change between the Control and Intervention arms at 6 weeks (- 0.13 mmol/L (95% CI [- 0.37, 0.11]), p = 0.29), however, we found that a DNA-personalised dietary intervention led to a significant reduction of FPG at 26 weeks in the Intervention arm when compared to standard care (- 0.019 (SD = 0.008), p = 0.01), as did the Exploratory arm (- 0.021 (SD = 0.008), p = 0.006). HbA1c at 26 weeks was significantly reduced in the Intervention arm when compared to standard care (- 0.038 (SD = 0.018), p = 0.04). There was some evidence suggesting prevention of progression to T2DM across the groups that received a DNA-based intervention (p = 0.06). Personalisation of dietary advice based on DNA did not result in glucose changes within the first 6 weeks but was associated with significant reduction of FPG and HbA1c at 26 weeks when compared to standard care. The DNA-based diet was effective regardless of intervention type, though results should be interpreted with caution due to the low sample size. These findings suggest that DNA-based dietary guidance is an effective intervention compared to standard care, but there is still a minimum timeframe of adherence to the intervention before changes in clinical outcomes become apparent.Trial Registration: www.clinicaltrials.gov.uk Ref: NCT03702465.

The Association Between Thymidylate Synthase Gene Polymorphisms and the Risk of Ischemic Stroke in Chinese Han Population

Family history of hypertension, smoking, diabetes and alcohol consumption and atherosclerotic plaque were identified as common risk factors in IS. We aimed at investigating the relationship between Thymidylate Synthase (TS) gene polymorphisms and ischemic stroke (IS).This case-control research selected and genotyped three single nucleotide polymorphisms (SNPs)of TS( rs699517, rs2790, and rs151264360) with Sanger sequencing in Chinese Han population. We also adopted logistic regression analysis in genetic models for calculating odds ratios and 95% confidence intervals. Genotype-Tissue Expression(GTEx) database analyzed the tissue-specific expression and TS polymorphisms. The ischemic stroke patients showed higher low-density lipoprotein cholesterol and total homocysteine (tHcy). It was found that patients with the TT genotype of rs699517 and GG genotype of rs2790 had larger degrees of tHcy than those with CC + CT genotypes and AA + AG genotypes, respectively. The genotype distribution of the three SNPs did not deviate from Hardy-Weinberg equilibrium (HWE). Haplotype analysis showed that T-G-del was the major haplotype in IS, and C-A-ins was the major haplotype in controls. GTEx database indicated that the rs699517 and rs2790 increased the expression of TS in healthy human and associated with TS expression level in a single tissue. In conclusion: This study has shown that TS rs699517 and rs2790 were significantly related to ischemic stroke patients.

The Multitarget Action of Vitamins in the Ischemic Stroke

A stroke, also known as a cerebral hemorrhage, occurs when there is an interruption in the blood supply to a part of the brain, resulting in damage to brain cells. This issue is one of the leading causes of death in developed countries, currently killing about 5 million people annually. Individuals who survive ischemic stroke often face serious vision problems, paralysis, dementia, and other sequelae. The numerous efforts to prevent and/or treat stroke sequelae seem insufficient, which is concerning given the increasing global elderly population and the well-known association between aging and stroke risk. In this review, we aim to present and discuss the importance of vitamins in stroke prevention and/or incidence. Vitamins from diet or dietary supplements influence the body at various levels; they are a relevant factor but are reported only in isolated articles. This review reports and updates the multitarget role of vitamins involved in reducing stroke risk.

Low vitamin B12 levels may predict the risk of ischemic stroke: A cross-sectional study

BACKGROUND

To examine serum vitamin B12 concentrations in relation to the risk of ischemic stroke among hospitalized patients in the Department of Neurology.

METHODS

We performed a cross-sectional study involving 2,212 inpatients discharged from the Department of Neurology of the First Affiliated Hospital of Chongqing Medical University, from January 2020 to January 2022. The results of laboratory assays such as serum vitamin B12, homocysteine, and folate levels were measured. Logistic regression analysis was used to investigate the association between serum vitamin B12 concentrations and ischemic stroke, with adjustment for a number of relevant demographic and lifestyle factors and comorbidities.

RESULTS

A total of 961 (43.4%) patients had an ischemic stroke. In the fully adjusted model, logistic regression analysis suggested a positive association between serum vitamin B12 levels<150 pg/mL (aOR: 1.42; 95% CI 1.02-1.97; p = 0.035), serum vitamin B12 150-300 pg/mL (aOR: 1.37; 95% CI 1.11-1.68; p = 0.003) and the prevalence of ischemic stroke. Furthermore, an inverse association was observed between serum vitamin B12 levels ≥ 900 pg/mL (aOR: 0.38; 95% CI: 0.19-0.77; p =0.007) and the prevalence of ischemic stroke. Moreover, the cut-off value of vitamin B12 concentration was 316.4 pg/mL and the discrimination power of the score evaluated by AUC-ROC was 0.71 (95%CI 0.68-0.73, p<0.001) in the vitamin B12 and ischemic stroke.

CONCLUSION

Findings suggest that low vitamin B12 levels may predict the risk of ischemic stroke, early and timely supplementation of vitamin B12 can improve the short-term prognosis of ischemic stroke patients.

New insights into the nutritional genomics of adult-onset riboflavin-responsive diseases

Riboflavin, or vitamin B2, is an essential nutrient that serves as a precursor to flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN). The binding of the FAD and/or FMN cofactors to flavoproteins is critical for regulating their assembly and activity. There are over 90 proteins in the human flavoproteome that regulate a diverse array of biochemical pathways including mitochondrial metabolism, riboflavin transport, ubiquinone and FAD synthesis, antioxidant signalling, one-carbon metabolism, nitric oxide signalling and peroxisome oxidative metabolism. The identification of patients with genetic variants in flavoprotein genes that lead to adult-onset pathologies remains a major diagnostic challenge. However, once identified, many patients with adult-onset inborn errors of metabolism demonstrate remarkable responses to riboflavin therapy. We review the structure:function relationships of mutant flavoproteins and propose new mechanistic insights into adult-onset riboflavin-responsive pathologies and metabolic dysregulations that apply to multiple biochemical pathways. We further address the vexing issue of how the inheritance of genetic variants in flavoprotein genes leads to an adult-onset disease with complex symptomologies and varying severities. We also propose a broad clinical framework that may not only improve the current diagnostic rates, but also facilitate a personalized approach to riboflavin therapy that is low cost, safe and lead to transformative outcomes in many patients.

Effects of vitamin B12 deficiency on risk and outcome of ischemic stroke

Ischemic stroke is the most prevalent form of stroke and has a high incidence in older adults, characterized by high morbidity, mortality, disability, and recurrence rate. Vitamin B₁₂ deficiency is prevalent in the elderly and has been reported to be associated with ischemic stroke. The mechanisms maybe include the disorder of methylation metabolism, accumulation of toxic metabolites, immune dysfunction, affecting gut microbial composition and gut-brain immune homeostasis, and toxic stress responses to the brain. Vitamin B₁₂ deficiency may lead to cerebral artery atherosclerosis, change myelination, influence the metabolism and transmission between nerve tissue, and ultimately causes the occurrence and development of ischemic stroke. This paper reviews the correlation between vitamin B₁₂ deficiency and ischemic stroke, looking forward to improving clinicians' understanding and providing new therapeutic directions for ischemic stroke.

Nutritional Factors: Benefits in Glaucoma and Ophthalmologic Pathologies

Glaucoma is a chronic optic neuropathy that can lead to irreversible functional and morphological damage if left untreated. The gold standard therapeutic approaches in managing patients with glaucoma and limiting progression include local drops, laser, and/or surgery, which are all geared at reducing intraocular pressure (IOP). Nutrients, antioxidants, vitamins, organic compounds, and micronutrients have been gaining increasing interest in the past decade as integrative IOP-independent strategies to delay or halt glaucomatous retinal ganglion cell degeneration. In our minireview, we examine the various nutrients and compounds proposed in the current literature for the management of ophthalmology diseases, especially for glaucoma. With respect to each substance considered, this minireview reports the molecular and biological characteristics, neuroprotective activities, antioxidant properties, beneficial mechanisms, and clinical studies published in the past decade in the field of general medicine. This study highlights the potential benefits of these substances in glaucoma and other ophthalmologic pathologies. Nutritional supplementation can thus be useful as integrative IOP-independent strategies in the management of glaucoma and in other ophthalmologic pathologies. Large multicenter clinical trials based on functional and morphologic data collected over long follow-up periods in patients with IOP-independent treatments can pave the way for alternative and/or coadjutant therapeutic options in the management of glaucoma and other ocular pathologies.

Association of methylenetetrahydrofolate reductase (MTHFR) rs1801133 (677C>T) gene polymorphism with ischemic stroke risk in different populations: An updated meta-analysis

Background: Recently, increasing evidence has implicated methylenetetrahydrofolate reductase (MTHFR) gene mutation as a risk factor for ischemic stroke (IS) in the general population. However, studies have been inconclusive and lack evidence on specific populations. We aim to determine whether the rs1801133 (NC_000001.11 (MTHFR):g. 677C>T (p.Ala222Val) variant, we termed as MTHFR rs1801133 (677 C>T), is linked to an increased risk of IS in different age groups and ancestry groups. Methods: The literature relevant to our study was found by searching the PubMed, Cochrane Library, Web of Science, EMBASE, and CNKI databases. A random effect model analysis was used to calculate the pooled odds ratio (OR) and 95% confidence interval (CI) to evaluate any possible association. We conducted a subgroup analysis based on the age and ancestry groups of the included populations. Results: As of March 2022, 1,925 citations had been identified in electronic databases, of which 96 studies involving 34,814 subjects met our eligibility criteria. A strong link was found between IS and the MTHFR gene rs1801133 (677C>T) polymorphism in all genetic models [dominant genetic model (OR = 1.47; 95%CI = 1.33-1.61; p < 0.001), recessive genetic model (OR = 1.52; 95%CI = 1.36-1.71; p < 0.001), heterozygous model (OR = 1.36; 95%CI = 1.24-1.48; p < 0.001), homozygous model (OR = 1.82; 95%CI = 1.58-2.11; p < 0.001), and T allelic genetic model (OR = 1.37; 95%CI = 1.27-1.48; p < 0.001)]. Further subgroup analyses indicated that the MTHFR rs1801133 (677C>T) variant may increase the risk of IS in Asian, Hispanic, or Latin population, middle-aged, and elderly populations (p < 0.001). Conclusion: Our results implied that mutation of the T allele of MTHFR rs1801133 (677C>T) could be a risk factor for IS. A significant association was found among Asian, Hispanic, or Latin population, middle-aged, and elderly people.

Role of Vitamins in Cardiovascular Health: Know Your Facts - Part 1

Cardiovascular (CV) disease (CVD) is a major cause of morbidity and mortality world-wide, thus it is important to adopt preventive interventions. Observational data demonstrating CV benefits of vitamin supplements, advanced by self-proclaimed experts have resulted in ~50% of Americans reporting the use of multivitamins for health promotion; this practice has led to a multi-billion-dollar business of the multivitamin-industry. However, the data on the extensive use of multivitamins show no consistent benefit for CVD prevention or all-cause mortality, while the use of certain vitamins might prove harmful. Thus, the focus of this two-part review is on the attributes or concerns about specific vitamins on CVD. In Part 1, the CV effects of specific vitamins are discussed, indicating the need for further supportive evidence of potential benefits. Vitamin A preserves CV homeostasis as it participates in many biologic functions, including atherosclerosis. However, supplementation could potentially be harmful. Betacarotene, a pro-vitamin A, conveys pro-oxidant actions that may mitigate any other benefits. Folic acid alone and certain B-vitamins (e.g., B1/B2/B6/B12) may reduce CVD, heart failure, and/or stroke, while niacin might increase mortality. Vitamin C has antioxidant and cardioprotective effects. Vitamin D may confer CV protection, but all the data are not in agreement. Combined vitamin E and C have antiatherogenic effects but clinical evidence is inconsistent. Vitamin K seems neutral. Thus, there are individual vitamin actions with favorable CV impact (certain B-vitamins and vitamins C and D), but other vitamins (β-carotene, niacin) may potentially have deleterious effects, which also holds true for high doses of fat-soluble vitamins (A/D/E/K).

Association of homocysteine and polymorphism of methylenetetrahydrofolate reductase with early-onset post stroke depression

Background

Homocysteine (Hcy) has been indicated to be involved in pathophysiology of post stroke depression (PSD). There is a lack of research to study the relationship between Hcy metabolism genes and PSD. Our study aims to investigate the relationship among Hcy metabolism genes, Hcy, and early-onset PSD.

Materials and methods

We recruited 212 patients with stroke and collected their peripheral blood sample, clinical data, and laboratory test on admission. 12 single nucleotide polymorphisms (SNPs) in methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), and methionine synthase (MTR) genes were genotyped by high-resolution melt analysis. PSD was diagnosed by DSM-V at 2 weeks after stroke. Binary logistic regression and haplotype analysis were used to examine the association between Hcy metabolism genes and PSD. Mediation analysis was performed to clarify whether the SNPs exerted their effect on PSD by affecting the Hcy level.

Results

81 patients were diagnosed with PSD, and the incidence rate was 38.2%. Hcy level in PSD group was significantly higher than it in non-PSD group (p = 0.019). MTHFR rs1801133 AA genotype an A allele were associated with an elevated risk of PSD after adjustment for some confounding factors (OR = 4.021, 95% CI: 1.459∼11.080, p = 0.007 for AA genotype; OR = 1.808, 95% CI: 1.172∼2.788, p = 0.007 for A allele). Furthermore, the effect of MTHFR rs1801133 AA genotype on PSD was mediated by Hcy (OR = 1.569, 95% CI: 0.013∼3.350, p < 0.05).

Conclusion

MTHFR rs1801133 and Hcy were associated with PSD, and MTHFR rs1801133 may exert an effect on PSD via mediating Hcy level. This offers a new perspective for treating PSD and understanding the mechanism of PSD.

Association of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms with vitamin B12 deficiency and adverse perinatal outcomes among pregnant women of rural South India - a cross sectional longitudinal study

OBJECTIVES

To determine the occurrence of MTHFR gene polymorphisms and to study their association with vitamin B12 deficiency and adverse perinatal outcomes among a cohort of pregnant women from Kaniyambadi block, Tamil Nadu.

METHODS

120 consecutive pregnant women who were ≤20 weeks of gestational age from the 82 villages of Kaniyambadi block were recruited. Genomic DNA was isolated from the peripheral blood. PCR amplification was done followed by Sangers sequencing. Maternal and neonatal outcomes were extracted. Data was entered and analysed.

RESULTS

Our study found the occurrence of c.1298A>C variant in homozygous state in 14.2% and c.677C>T heterozygous state in 15%. Sanger sequencing of exon 7 identified another pathogenic variant c.1262G>T in heterozygous state in two of them. Both the mothers who harboured that variant had preterm delivery and one of them gave birth to a low-birth-weight neonate. In the entire cohort, 5% of the mothers had abortion, 4.2% of them had preterm delivery and 8.8% of the neonates had low birth weight. Presence of c.1298A>C or c.677C>T variants were associated with vitamin B12 deficiency [Pearson Chi squared value (χ²)=7.9 and 7.6 respectively; p=0.02]. Heterozygous pathogenic variant c.1262G>T was associated with both adverse maternal [χ²=11.5; p=0.001] and neonatal [χ²=18.3; p=0.009] outcomes.

CONCLUSIONS

MTHFR gene polymorphisms could be associated with several adverse perinatal outcomes and vitamin B12 deficiency. Further larger studies are needed to prove the pathogenicity of c.1262G>T variant on pregnancy.

Association between plasma total homocysteine (tHcy) and strokes: A meta-analysis

Objective

Inconsistent findings have been reported regarding the association between elevated plasma total homocysteine (tHcy) and the risk of different types of strokes. We conducted this meta-analysis to identify the association between tHcy and different kinds of strokes or recurrences of strokes, and provide evidence for preventing.

Methods

Relevant studies published before May 1, 2022 in databases such as PubMed, EMBASE, the Cochrane Library, CNKI, and Wanfang were retrieved. Two researchers independently searched and extracted the data, and used Stata 16.0 statistical software for analysis. Results were presented as the odds risk (OR) and the corresponding 95% confidence intervals (CI).

Results

In total, 24 articles were included, involving 51,426 subjects, of which 4,983 had stroke events during follow-up. Relative to lower tHcy, higher tHcy were associated with increased stroke (OR = 1.95, 95% CI: 1.59–2.37), ischemic stroke (OR = 1.71, 95% CI: 1.39–2.11), hemorrhagic stroke (OR = 1.99, 95% CI: 1.03–3.84), and recurrent stroke (OR = 1.25, 95% CI: 1.12–1.39), respectively.

Conclusions

This study shows that elevated tHcy increases the risk of stroke, including ischemic stroke and hemorrhagic stroke, and is closely related to the recurrence of stroke. It is recommended to pay attention to the detection of tHcy in the management of stroke patients in the future, and take effective measures to prevent and delay the progression of stroke.

Effect of methylenetetrahydrofolate reductase C677T polymorphism on serum folate but not vitamin B12 levels in patients with H-type hypertension

BACKGROUND

Hyperhomocysteinemia (HHcy) is a common complication in Chinese hypertensive patients and associated with methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, folate, and vitamin B12 (Vit B12) status. This study evaluated the associations of MTHFR C677T polymorphism, folate, and Vit B12 with H-type hypertension.

METHODS AND RESULTS

887 eligible patients with essential hypertension were included. Patients were divided into two groups according to the Hcy level, the H-type hypertension group and the normal hypertension group. Related risk factors such as MTHFR polymorphism, folate and Vit B12 status were analyzed in the two groups. Age, gender, SBP, DBP, MTHFR C677T genotype, folate and Vit B12 differed significantly between H-type hypertension and normal hypertension groups (P < 0.05). MTHFR 677TT variant, gender, folate, and Vit B12 were independent risk factors for the occurrence of H-type hypertension. The risk for TT carriers was 8 times higher than that of CC and CT carriers [OR (95% CI) 8.248 (5.274-12.899)]. Male patients had almost fivefold higher odds than female patients [OR (95% CI) 4.923 (2.741-8.842)]. Folate level of patients with H-type hypertension decreased with the C to T substitution of MTFHR C677T gene (P < 0.05), while Vit B12 level was not associated with the gene (P > 0.05).

CONCLUSIONS

MTHFR 677TT variant, gender, folate, and Vit B12 were risk factors for the occurrence of H-type hypertension. Folate but not Vit B12 was associated with MTFHR C677T polymorphism in patients with H-type hypertension. Accordingly, the above factors may be considered in the prevention and treatment of hypertension.

Tackling Atherosclerosis via Selected Nutrition

The development and pathogenesis of atherosclerosis are significantly influenced by lifestyle, particularly nutrition. The modern level of science and technology development promote personalized nutrition as an efficient preventive measure against atherosclerosis. In this survey, the factors were revealed that contribute to the formation of an individual approach to nutrition: genetic characteristics, the state of the microbiota of the gastrointestinal tract (GIT) and environmental factors (diets, bioactive components, cardioprotectors, etc.). In the course of the work, it was found that in order to analyze the predisposition to atherosclerosis associated with nutrition, genetic features affecting the metabolism of nutrients are significant. The genetic features include the presence of single nucleotide polymorphisms (SNP) of genes and epigenetic factors. The influence of telomere length on the pathogenesis of atherosclerosis and circadian rhythms was also considered. Relatively new is the study of the relationship between chrono-nutrition and the development of metabolic diseases. That is, to obtain the relationship between nutrition and atherosclerosis, a large number of genetic markers should be considered. In this relation, the question arises: "How many genetic features need to be analyzed in order to form a personalized diet for the consumer?" Basically, companies engaged in nutrigenetic research and choosing a diet for the prevention of a number of metabolic diseases use SNP analysis of genes that accounts for lipid metabolism, vitamins, the body's antioxidant defense system, taste characteristics, etc. There is no set number of genetic markers. The main diets effective against the development of atherosclerosis were considered, and the most popular were the ketogenic, Mediterranean, and DASH-diets. The advantage of these diets is the content of foods with a low amount of carbohydrates, a high amount of vegetables, fruits and berries, as well as foods rich in antioxidants. However, due to the restrictions associated with climatic, geographical, material features, these diets are not available for a number of consumers. The way out is the use of functional products, dietary supplements. In this approach, the promising biologically active substances (BAS) that exhibit anti-atherosclerotic potential are: baicalin, resveratrol, curcumin, quercetin and other plant metabolites. Among the substances, those of animal origin are popular: squalene, coenzyme Q10, omega-3. For the prevention of atherosclerosis through personalized nutrition, it is necessary to analyze the genetic characteristics (SNP) associated with the metabolism of nutrients, to assess the state of the microbiota of the GIT. Based on the data obtained and food preferences, as well as the individual capabilities of the consumer, the optimal diet can be selected. It is topical to exclude nutrients of which their excess consumption stimulates the occurrence and pathogenesis of atherosclerosis and to enrich the diet with functional foods (FF), BAS containing the necessary anti-atherosclerotic, and stimulating microbiota of the GIT nutrients. Personalized nutrition is a topical preventive measure and there are a number of problems hindering the active use of this approach among consumers. The key factors include weak evidence of the influence of a number of genetic features, the high cost of the approach, and difficulties in the interpretation of the results. Eliminating these deficiencies will contribute to the maintenance of a healthy state of the population through nutrition.

Association Between Atorvastatin Exposure and Low Folate Status: A Case-Control Study

Objective

The objective of this study is to assess the association between exposure to atorvastatin (ATV) and low-plasma folate (PF) status.

Methods

The sample consisted of patients admitted to the internal medicine service of a basic general hospital, located in Zaragoza (Spain). We adopted a pharmacoepidemiological case-control study design. For this, the number of treatment days (TDs) of all the drugs part of their treatment during the study period was obtained from each patient in the sample. The cases were comprised by the number of patient's TDs for which PF ≤3 mg/dl and the controls by the number of patient's TDs for which PF >3 mg/dl. To measure the strength of the association, the odds ratios (ORs) were calculated. The Chi-square test, using the Bonferroni correction, was used to calculate the statistical significance.

Findings

The sample consisted of 640 polymedicated patients. The mean PF obtained were 8.0 ± 4.6 mg/dl and 2.1 ± 0.6 mg/dl, for the cases and controls, respectively; the total number of TDs for the cases and controls were 7615 and 57899, respectively. We obtained a U-shaped curve when representing the dose of ATV against the corresponding ORs when comparing cases with control.

Conclusion

Exposure to ATV at 10 or 80 mg is associated with an augmented risk of low folate status. We recommend implementing guidelines for mandatory folic acid fortification in patients exposed to ATV doses of 10 or 80 mg.

Problem in the Recent American Heart Association Guideline on Secondary Stroke Prevention: B Vitamins to Lower Homocysteine Do Prevent Stroke

In this article, we discuss a problem in the most recent American Heart Association guideline on secondary stroke prevention that apparently arose from the rules of evidence imposed on the guideline panel. We are told by the cochair of the panel that American Heart Association rules about guidelines for secondary prevention prohibited consideration of primary prevention studies and secondary analyses of secondary prevention studies. However, evidence-based medicine should consider all the best external evidence available and also clinical judgement. The most important problem in the guideline was the recommendation that B vitamins to lower homocysteine do not prevent recurrent stroke. When considering all the best external evidence, it is clear that B vitamins do prevent stroke, but in the early secondary stroke prevention studies, the benefit of B vitamins in participants with good renal function was apparently offset by harm from cyanocobalamin among participants with renal failure (level B-R evidence). We review the evidence that B vitamins should be used to prevent stroke, both in primary and secondary stroke prevention (class 2a recommendation). We also review issues in folate metabolism that require further study, with regard to the form of folate to be used for stroke prevention. We recommend that the guideline be revised to say that B vitamins to lower homocysteine prevent stroke and that methylcobalamin or hydroxycobalamin should be used instead of cyanocobalamin.

Detecting Key Functional Components Group and Speculating the Potential Mechanism of Xiao-Xu-Ming Decoction in Treating Stroke

Stroke is a cerebrovascular event with cerebral blood flow interruption which is caused by occlusion or bursting of cerebral vessels. At present, the main methods in treating stroke are surgical treatment, statins, and recombinant tissue-type plasminogen activator (rt-PA). Relatively, traditional Chinese medicine (TCM) has widely been used at clinical level in China and some countries in Asia. Xiao-Xu-Ming decoction (XXMD) is a classical and widely used prescription in treating stroke in China. However, the material basis of effect and the action principle of XXMD are still not clear. To solve this issue, we designed a new system pharmacology strategy that combined targets of XXMD and the pathogenetic genes of stroke to construct a functional response space (FRS). The effective proteins from this space were determined by using a novel node importance calculation method, and then the key functional components group (KFCG) that could mediate the effective proteins was selected based on the dynamic programming strategy. The results showed that enriched pathways of effective proteins selected from FRS could cover 99.10% of enriched pathways of reference targets, which were defined by overlapping of component targets and pathogenetic genes. Targets of optimized KFCG with 56 components can be enriched into 166 pathways that covered 80.43% of 138 pathways of 1,012 pathogenetic genes. A component potential effect score (PES) calculation model was constructed to calculate the comprehensive effective score of components in the components-targets-pathways (C-T-P) network of KFCGs, and showed that ferulic acid, zingerone, and vanillic acid had the highest PESs. Prediction and docking simulations show that these components can affect stroke synergistically through genes such as MEK, NFκB, and PI3K in PI3K-Akt, cAMP, and MAPK cascade signals. Finally, ferulic acid, zingerone, and vanillic acid were tested to be protective for PC12 cells and HT22 cells in increasing cell viabilities after oxygen and glucose deprivation (OGD). Our proposed strategy could improve the accuracy on decoding KFCGs of XXMD and provide a methodologic reference for the optimization, mechanism analysis, and secondary development of the formula in TCM.

Relation of BMI and waist circumference with the risk of new-onset hyperuricemia in hypertensive patients

BACKGROUND

We aimed to evaluate the relationship of body mass index (BMI) and waist circumference (WC) with the risk of new-onset hyperuricemia, and examine possible effect modifies in general hypertensive patients.

METHODS

A total of 10 611 hypertensive patients with normal uric acid (UA) concentrations (<357 μmol/l) at baseline were included from the UA sub-study of the China Stroke Primary Prevention Trial. The primary outcome was new-onset hyperuricemia, defined as a UA concentration ≥417 μmol/l in men or ≥357 μmol/l in women at the exit visit.

RESULTS

During a median follow-up duration of 4.4 years, 1663 (15.7%) participants developed new-onset hyperuricemia. When analyzed separately, increased BMI (≥25 kg/m2, quartile 3-4; OR, 1.46; 95% CI: 1.29-1.65), or increased WC (≥85 cm for females, quartile 3-4; OR, 1.24; 95% CI: 1.08-1.42; and ≥84 cm for males, quartile 3-4; OR, 1.30; 95% CI: 1.01-1.67) were each significantly associated with higher risk of new-onset hyperuricemia. When WC was forced into the model with BMI simultaneously, its significant association with new-onset hyperuricemia disappeared in females (<85 vs. ≥85 cm; OR, 0.96, 95% CI: 0.81-1.13) or males (≥84 vs. <84 cm; OR, 1.13; 95% CI: 0.84-1.52); however, BMI was still significantly related with new-onset hyperuricemia (≥25 vs. <25 kg/m2; OR, 1.48; 95% CI: 1.27-1.73). Moreover, the positive BMI & new-onset hyperuricemia association was more pronounced in participants with higher time-averaged on-treatment systolic blood pressure (median: <138.3 vs. ≥138.3 mmHg; P-interaction = 0.041).

CONCLUSIONS

Higher BMI, but not WC, is significantly and independently associated with an increased risk of new-onset hyperuricemia among hypertensive patients.

MTHFR 677TT is associated with decreased number of embryos and cumulative live birth rate in patients undergoing GnRHa short protocol: a retrospective study

Background

Whether MTHFR C677T genotype affects pregnancy outcomes following assisted reproductive technology is conflicting. And the role of MTHFR C677T genotype on cumulative live birth has not been reported. This study aims to investigate the effect of MTHFR C677T genotype on cumulative live birth following in-vitro fertilization and embryo transfer (IVF-ET).

Methods

This is a retrospective cohort study that includes 1173 women undergoing their first IVF-ET. We retrospectively compared the reproductive outcomes among the groups stratified by MTHFR C677T genotypes (677CC, 677CT, 677TT). We performed interaction analysis to detect the factor that interacts with the MTHFR C677T genotype. Poisson regression analyses were used to evaluate the associations between MTHFR C677T genotypes with the number of transferable embryos and the number of good-quality embryos. Cox regression analysis was used to evaluate the association between MTHFR C677T genotypes with cumulative live birth. All regression analyses were adjusted with the confounding factors which may independently impact reproductive outcomes.

Results

There is a significant interactive effect of MTHFR 677TT genotype with GnRHa protocol on reproductive outcomes (P for interaction<0.05). MTHFR 677TT homozygous mutation was found to impact reproductive outcomes under GnRHa short protocol but not GnRHa long protocol. MTHFR 677TT is significantly associated with decreased number of transferable embryos (p-value=0.028), decreased number of good-quality embryos (p-value=0.005), and decreased cumulative live birth rate (p-value=0.024) in patients undergoing GnRHa short protocol. However, the clinical pregnancy rate, miscarriage rate and live birth rate at the first embryo transfer cycle were not significantly different between the groups under both protocols (p-values>0.05).

Conclusions

MTHFR 677TT genotype is associated with decreased number of transferable embryos, decreased number of good-quality embryos, and decreased cumulative live birth rate in the first complete cycle in patients undergoing GnRHa short protocol.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04506-4.

Association between serum folate levels and blood concentrations of cadmium and lead in US adults

BACKGROUND

Folate may be involved in the detoxification of heavy metals. This has been demonstrated in animal studies, in in vivo and in vitro studies, and clinical evaluations. However, knowledge regarding the associations between serum folate and blood concentrations of cadmium and lead is limited.

OBJECTIVE

We aimed to investigate the relationship between serum folate levels and blood concentrations of cadmium and lead in US adults.

METHODS

Data on 15,501 adults were obtained from the 1999-2006 National Health and Nutrition Examination Survey (NHANES) and used for the analysis. Information on serum folate concentrations and blood levels of lead and cadmium was derived from laboratory measurements in the NHANES. Multivariable linear regression was used to examine the relationship between serum folate levels and blood concentrations of cadmium and lead in US adults, controlling for confounders.

RESULTS

The serum folate concentration was negatively correlated with blood levels of cadmium and lead (P-trends <0.01). When stratified by sex (male and female) and estimated glomerular filtration rate (eGFR ≤60 and >60 mL/min/1.73 m²), the association between serum folate concentrations and blood levels of cadmium and lead was found to be more stable in adults with eGFR > 60 mL/min/1.73 m², both in males and females.

SIGNIFICANCE

These findings warrant future studies to explore the mechanisms responsible for the beneficial role of folate in regulating cadmium and lead concentrations in the blood.

Role of Vitamin B12 and Folate in Metabolic Syndrome

Metabolic syndrome (MS) is a collection of pathological metabolic conditions that includes insulin resistance, central or abdominal obesity, dyslipidemia, and hypertension. It affects large populations worldwide, and its prevalence is rising exponentially. There is no specific mechanism that leads to the development of MS. Proposed hypotheses range from visceral adiposity being a key factor to an increase in very-low-density lipoprotein and fatty acid synthesis as the primary cause of MS. Numerous pharmaceutical therapies are widely available in the market for the treatment of the individual components of MS. The relationship between MS and vitamin B complex supplementation, specifically folic acid and vitamin B12, has been a subject of investigation worldwide, with several trials reporting a positive impact with vitamin supplementation on MS.

In this study, an all-language literature search was conducted on Medline, Cochrane, Embase, and Google Scholar till September 2021. The following search strings and Medical Subject Headings (MeSH) terms were used: “Vitamin B12,” “Folate,” “Metabolic Syndrome,” and “Insulin Resistance.” We explored the literature on MS for its epidemiology, pathophysiology, newer treatment options, with a special focus on the effectiveness of supplementation with vitamins B9 and B12.

According to the literature, vitamin B12 and folate supplementation, along with a host of novel therapies, has a considerable positive impact on MS. These findings must be kept in mind while designing newer treatment protocols in the future.

Molecular Analysis of Prothrombotic Gene Variants in Patients with Acute Ischemic Stroke and with Transient Ischemic Attack

Background and objectives: ischemic stroke (IS) is among the most frequent causes of death worldwide; thus, it is of paramount relevance to know predisposing factors that may help to identify and treat the high-risk subjects. Materials and Methods:we tested nine variants in genes involved in thrombotic pathway in 282 patients that experienced IS and 87 that had transient ischemic attacks (TIA) in comparison to 430 subjects from the general population (GP) of the same geographic area (southern Italy). We included cases of young and child IS to evaluate the eventual differences in the role of the analyzed variants. Results: we did not observe significant differences between TIA and the GP for any of the variants, while the allele frequencies of methylene-tetrahydrofolate reductase (MTHFR) C677T, beta-fibrinogen -455G>A and factor (FXIII) V34L were significantly higher in patients with IS than in the subjects from the GP. No significant interaction was observed with sex. Conclusions: the present data argue that some gene variants have a role in IS and this appears to be an interesting possibility to be pursued in large population studies to help design specific strategies for IS prevention.

Prospective association between baseline plasma zinc concentration and development of proteinuria in Chinese hypertensive patients

OBJECTIVE

We aimed to evaluate the association between baseline plasma zinc and the development of proteinuria as well as possible effect modifiers in hypertensive patients.

METHODS

This is a subset of the China Stroke Primary Prevention Trial (CSPPT) Renal Sub-Study. In the CSPPT, participants were randomized to receive a daily oral dose of 1 tablet containing 10 mg enalapril and 0.8 mg folic acid or 1 tablet containing 10 mg enalapril only. A total of 783 participants with plasma zinc measurements and without proteinuria at baseline were included in the current study. The study outcome was the development of proteinuria during the follow-up, defined as a urine dipstick reading of trace or ≥1+ at the exit visit.

RESULTS

During a median follow-up duration of 4.4 years, the development of proteinuria occurred in 93 (11.9 %) participants. There was an inverse relation of baseline plasma zinc with the development of proteinuria (per SD increment; OR, 0.74, 95 % CI: 0.55-0.99), p for trend of quartiles = 0.005.

CONCLUSIONS

In Chinese hypertensive patients, there was a significant inverse association between baseline plasma zinc and the development of proteinuria, although plasma zinc remained in the reference range.

The role of dietary supplements that modulate one-carbon metabolism on stroke outcome

PURPOSE OF REVIEW

Ischemic stroke results in disability and mortality worldwide. Nutrition is a modifiable risk factor for stroke. For example, deficiencies in one-carbon metabolism have been linked to increased risk of stroke through elevated levels of homocysteine. Some countries world-wide fortify their diets with folates to prevent neural tube defects, but deficiencies in other one-carbon metabolites, such as vitamin B12 and choline are still present in many populations. The aim of this review is to understand the current evidence on how dietary supplementation by nutrients which modulate one-carbon metabolism impact stroke outcome.

RECENT FINDINGS

The results from clinical studies evaluating lowering homocysteine through B-vitamin supplementation on stroke risk remain unclear. Other clinical and preclinical studies have shown increasing dietary intake of one-carbon metabolism has some benefit on stroke outcome. Preclinical studies have shown that increased levels of nutrients which modulate one-carbon metabolism help facilitate recovery in damage models of the central nervous system. One the mechanisms driving these changes is neuroplasticity.

SUMMARY

The data suggest that increasing dietary nutrients that modulate one-carbon metabolites in patients that are at a higher risk for and suffer from central nervous system diseases, such as stroke, could benefit in addition to other therapies.

Role of vitamin B12 deficiency in ischemic stroke risk and outcome

Currently, ischemic stroke is the most prevalent form of stroke compared to hemorrhagic and there is a high incidence in older adults. Nutrition is a modifiable risk factor for stroke. B-vitamins are part of a metabolic network that integrates nutritional signals with biosynthesis, redox homeostasis, and epigenetics. These vitamins play an essential role in the regulation of cell proliferation, stress resistance, and embryo development. A deficiency in vitamin B12 is common in older adults and has been reported to be implicated in ischemic stroke. The aim of this review was to investigate whether vitamin B12 deficiencies impact the risk and outcome of ischemic stroke. Clinical data from our literature review strongly suggest that a deficiency in vitamin B12 is a risk factor for ischemic stroke and possible outcome. Our survey of the literature has identified that there is a gap in the understanding of the mechanisms through which a vitamin B12 deficiency leads to an increased risk of stroke and outcome. A vitamin B12 deficiency can increase homocysteine levels, which are a well-established risk factor for ischemic stroke. Another potential mechanism through which vitamin B12 deficient may impact neurological function and increase risk of stroke, is changes in myelination, however this link requires further investigation. Further studies are required in model systems to understand how a vitamin B12 deficiency changes the brain.

COVID-19-associated stroke risk: Could nutrition and dietary patterns have a contributing role?

The novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 has created a life-threatening world pandemic. Unfortunately, this disease can be worse in older patients or individuals with comorbidities, having dangerous consequences, including stroke. COVID-19–associated stroke widely increases the risk of death from COVID-19. In addition to the personal hygiene protocols and preventive policies, it has been proven that immune-compromised, oxidative, and pro-coagulant conditions make a person more susceptible to severe COVID-19 complications, such as stroke; one of the most effective and modifiable risk factors is poor nutritional status. Previous literature has shown that healthy dietary patterns, such as the Mediterranean diet, some food groups, and specific micronutrients, reduce the risk of ischemic and hemorrhagic stroke. In this work, for the first time, we hypothesized that a healthy diet could also be a protective/preventive factor against COVID-19–associated stroke risk. In order to prove this hypothesis, it is required to study nutritional intake and dietary patterns in patients suffering from COVID-19–associated stroke. If this hypothesis is proven, the chronic supportive role of a healthy diet in critical situations will be highlighted once again.

Degree of blood pressure control and the risk of new-onset hyperuricemia in treated hypertensive patients

Background

The relationship between blood pressure (BP) control and the risk of new-onset hyperuricemia remains uncertain. We aimed to examine the association between degree of time-averaged on-treatment BP control and new-onset hyperuricemia in general hypertensive patients.

Methods

A total of 10,617 hypertensive patients with normal uric acid (UA) concentrations (<357 µmol/L) at baseline were included from the UA Sub-study of the China Stroke Primary Prevention Trial (CSPPT). Participants were randomized to receive a double-blind daily treatment of enalapril 10 mg and folic acid 0.8 mg or enalapril 10 mg alone. BP measurements were taken every three months after randomization. The primary outcome was new-onset hyperuricemia, defined as a UA concentration ≥417 µmol/L in men or ≥357 µmol/L in women at the exit visit.

Results

Over a median of 4.4 years, 1,664 (15.7%) participants developed new-onset hyperuricemia. Overall, there was a significantly positive association between time-averaged on-treatment diastolic BP (DBP) and new-onset hyperuricemia (per 10 mmHg increment; OR 1.13; 95% CI: 1.02–1.26). Consistently, a significantly higher risk of new-onset hyperuricemia was found in participants with time-averaged on-treatment DBP ≥82.9 mmHg (median) (vs. <82.9 mmHg; 17.3% vs. 14.1%; OR 1.25; 95% CI: 1.10–1.44). Furthermore, the lowest new-onset hyperuricemia risk (12.1%) was found in those with both time-averaged on-treatment SBP (median: 138.3 mmHg) and DBP below the median (P-interaction=0.023). The results were similar for time-averaged DBP during the first 12- or 24-month treatment period, or in the analysis using propensity scores. Furthermore, a non-significant higher risk of new-onset hyperuricemia was observed in participants with time-averaged on-treatment SBP ≥120 mmHg (vs. <120 mmHg; OR 1.61; 95% CI: 0.88–2.97).

Conclusions

A tight DBP control of <82.9 mmHg was associated with lower risk of new-onset hyperuricemia among hypertensive patients without hyperuricemia.

Management of asymptomatic carotid stenosis

Patients with asymptomatic carotid stenosis (ACS) are at very high risk of coronary events, so they should all receive intensive medical therapy. What is often accepted as “best medical therapy” is usually suboptimal. Truly intensive medical therapy includes lifestyle modification, particularly smoking cessation and a Mediterranean diet. All patients with ACS should receive intensive lipid-lowering therapy, should have their blood pressure well controlled, and should receive B vitamins for lowering of plasma total homocysteine (tHcy) if levels are high; a commonly missed cause of elevated tHcy is metabolic B12 deficiency, which should be diagnosed and treated. Most patients with ACS would be better treated with intensive medical therapy than with either carotid endarterectomy (CEA) or stenting (CAS). A process called “treating arteries instead of treating risk factors” markedly reduced the risk of ACS in an observational study; a randomized trial vs. usual care should be carried out. The few patients with ACS who could benefit (~15%, or perhaps more if recent evidence regarding the risk of intraplaque hemorrhage is borne out) can be identified by a number of features. These include microemboli on transcranial Doppler, intraplaque hemorrhage, reduced cerebrovascular reserve, and echolucency of plaques, particularly “juxtaluminal black plaque”. No patient should be subjected to CAS or CEA without evidence of high-risk features, because in most cases the 1-year risk of stroke or death with intervention is higher with either CEA (~2%) or CAS (~4%) than with intensive medical therapy (~0.5%). Most patients, particularly the elderly, would be better treated with CEA than CAS. Most strokes can be prevented in patients with ACS, but truly intensive medical therapy is required.

Recent advances in preventing recurrent stroke

Since a 2017 update, there have been important advances in stroke prevention. These include new evidence about nutrition, antiplatelet therapy, anticoagulation, lipid-lowering therapy, hypertension control, pioglitazone, and carotid endarterectomy and stenting. Evidence regarding toxic metabolites produced by the intestinal microbiome from egg yolk and red meat has important dietary implications, particularly for patients with impaired renal function, including the elderly. They should avoid egg yolk and red meat and limit the intake of animal flesh. Higher doses of folic acid may be needed for patients with the T allele of MTHFR, so it may not be sufficient to give vitamin B12 (methylcobalamin) alone, even in countries with folate fortification. There is now good evidence that lipid-lowering therapy is even more beneficial in the elderly than in younger patients; we should be using lipid-lowering therapy more intensively, often/usually combining statins with ezetimibe. There is new evidence that lower systolic blood pressure targets are better for most patients, but a subgroup with stiff arteries, a wide pulse pressure, and a diastolic pressure of <60 would be more likely to be harmed than helped by aiming for a systolic target of <120 mmHg. There is a better understanding of how the pharmacological properties of direct-acting oral anticoagulants and the metabolism of antiplatelet agents should inform decisions about the use of these agents. Pioglitazone markedly reduces the risk of stroke, both in diabetics and prediabetics; it should be used more widely. It is now clear that carotid endarterectomy is safer than stenting and that the difference is strongly affected by age. Most patients, and in particular older patients, would be better served by endarterectomy than stenting.

Stroke Prevention

In 44 years of practicing stroke prevention, I have learned many lessons; in this article, I hope to impart some of them. Three areas of my research are discussed. Controlling resistant hypertension is markedly improved by physiologically individualized therapy based on renin/aldosterone phenotyping; this is particularly important in black patients. Measurement of carotid plaque burden strongly predicts cardiovascular risk and is useful for genetic research and for a process called treating arteries instead of risk factors. Doing so in high-risk patients with asymptomatic carotid stenosis was associated with a >80% reduction in the 2-year risk of stroke and myocardial infarction. It also permitted the identification of extremes of atherosclerosis that are useful for studying both the genetics and the biology of atherosclerosis. Patients with very high plaque burden despite low levels of risk factors have an unexplained phenotype; those with little or no plaque despite high levels of risk factors are protected. Patients with unexplained atherosclerosis have higher plasma levels of toxic metabolites produced by the intestinal microbiome largely from egg yolk, red meat, and protein, and those metabolites are renally excreted. This has important dietary implications for stroke prevention. Lowering of plasma total homocysteine with B vitamins significantly reduces the risk of stroke. That was not apparent in early studies because harm from cyanocobalamin among participants with renal failure obscured the benefit among those with good renal function. We should be using B vitamins to prevent stroke but should use methylcobalamin or oxocobalamin instead of cyanocobalamin.

Choosing the right therapy for a patient with asymptomatic carotid stenosis

Introduction: Most patients with asymptomatic carotid stenosis (ACS) now have a lower risk with intensive medical therapy than with stenting (CAS) or endarterectomy (CEA); the annual risk of stroke or death with intensive medical therapy is ~ 0.5%, vs. a periprocedural risk with CAS of ~ 2.5-4.1% with CAS, and ~ 1.4-1.8% with CEA. The excess risk of CAS is greater in older patients.Areas covered: Discussed are the need for intensive medical therapy, the nature of intensive medical therapy, approaches to identifying the few patients with ACS who could benefit from CEA or CAS, and which patients would be better suited to CEA vs. CAS.Expert opinion: All patients with ACS are at high risk of cardiovascular events, soshould receive intensive medical therapy including lifestyle modification, intensive lipid-lowering, B vitamins to lower homocysteine (using methylcobalamin rather than cyanocobalamin), and appropriate antithrombotic therapy. High-risk patients who could benefit from intervention can be identified by clinical and imaging features including transcranial Doppler embolus detection, ulceration, intraplaque hemorrhage, reduced cerebrovascular reserve, plaque echolucency, silent infarction on brain imaging, and progression of stenosis. Most patients whose risk of stroke warrants intervention would be better treated with CEA than with CAS.