Relevance of plasma levels of free homocysteine and methionine as risk predictors for ischemic stroke in the young

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.

Association between Variation in Body Fat Mass Magnitude and Intake of Nutrients, including Carbohydrates, Fat, and B Vitamins, in a Cohort of Highly Trained Female Athletes

The most common sports nutrition strategies were constructed not only for maximizing musculoskeletal adaptations to exercise, but also to minimize health risks in athletes. Given the lack of research highlighting the potential effects of the intake of carbohydrates, fats, and B vitamins on body fat percentage in a population of female athletes, this study aimed to elucidate whether the intake of macronutrients and B vitamins could be associated with the variation in body fat percentage in a cohort of professional female athletes. This cross-sectional study was weighted to represent Lithuanian elite female athletes (n = 89). The dietary assessment of the female athletes was carried out using a 3-day dietary recall method. Their body composition was assessed using the bioelectrical impedance analysis method. For females, the reported average intakes of energy, carbohydrates, protein, and fat were 2475 kcal/day, 5.1 g/kg/day, 1.5 g/kg/day, and 36.7%, respectively. Excess B vitamin intake was revealed, ranging within plus 1-2 standard deviations (SDs) around the mean requirements. As a consequence, excessive body fat percentage was potentially factored as a negative outcome in maintaining optimal body composition in female athletes. Multivariate logistic regression analysis of a sample of female athletes revealed that, despite a slightly positive energy balance (∆ 95 kcal/day), the carbohydrate-deficient diet (adjusted odds ratio (aOR) 0.3, 95% confidence interval (CI) 0.1; 0.7), along with higher intakes of vitamin B1 (aOR 2.9, 95% CI 2.6; 7.8), vitamin B2 (aOR 6.7, 95% CI 1.1; 8.3), and vitamin B3 (aOR 1.8, 95% CI 1.4; 7.8) from food, was associated with a lower percentage of body fat. Therefore, more attention should be given to the intake of B vitamins in professional athletes with a range of body fat mass percentages for the purpose of achieving long-term goals of maintaining body composition and fitness.

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.

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.

Factors Related to Plasma Homocysteine Concentration in Young Adults: A Retrospective Study Based on Checkup Populations

The distribution profile of plasma homocysteine (Hcy) in young adults and its related factors are not well understood. We performed a generalized estimating equations (GEE) analysis for plasma-Hcy-correlated factors in 2436 young adults, aged 20-39 years, from a health checkup population. We observed that the mean Hcy concentration in males (16.7 ± 10.3 μmol/L) was significantly higher than that in females (10.3 ± 4.0 μmol/L), and hyperhomocysteinemia (HHcy) prevalence in males was 5.37 times than that in females (33.3% vs. 6.2%). A GEE analysis stratified by sex indicated that age (B = -0.398, p < 0.001) and LDL-C (B = -1.602, p = 0.043) were negatively correlated, while BMI (B = 0.400, p = 0.042) was positively correlated, with the Hcy level in young males. ALT (B = -0.021, p = 0.033), LDL-C (B = -1.198, p < 0.001) and Glu (B = -0.446, p = 0.006) were negatively correlated, while AST (B = 0.022, p = 0.048), CREA (B = 0.035, p < 0.001), UA (B = 0.004, p = 0.003) and TG (B = 1.042, p < 0.001) were positively correlated, with the Hcy level in young females. These results suggest that young males have a significantly higher plasma Hcy level and HHcy prevalence than young females; therefore, more attention should be paid to the reason for and effect of the higher HHcy prevalence in young males.

Causal effects of B vitamins and homocysteine on obesity and musculoskeletal diseases: A Mendelian randomization study

Objectives

Although homocysteine (Hcy) increases the risk of cardiovascular diseases, its effects on obesity and musculoskeletal diseases remain unclear. We performed a Mendelian randomization study to estimate the associations between Hcy and B vitamin concentrations and their effects on obesity and musculoskeletal-relevant diseases in the general population.

Methods

We selected independent single nucleotide polymorphisms of Hcy (n = 44,147), vitamin B12 (n = 45,576), vitamin B6 (n = 1864), and folate (n = 37,465) at the genome-wide significance level as instruments and applied them to the studies of summary-level data for fat and musculoskeletal phenotypes from the UK Biobank study (n = 331,117), the FinnGen consortium (n = 218,792), and other consortia. Two-sample Mendelian randomization (MR) approaches were utilized in this study. The inverse variance weighting (IVW) was adopted as the main analysis. MR-PRESSO, MR-Egger, the weighted median estimate, bidirectional MR, and multivariable MR were performed as sensitivity methods.

Results

Higher Hcy concentrations were robustly associated with an increased risk of knee osteoarthritis [odds ratio (OR) 1.119; 95% confidence interval (CI) 1.032-1.214; P = 0.007], hospital-diagnosed osteoarthritis (OR 1.178; 95% CI 1.012-1.37; P = 0.034), osteoporosis with pathological fracture (OR 1.597; 95% CI 1.036-2.46; P = 0.034), and soft tissue disorder (OR 1.069; 95% CI 1.001-1.141; P = 0.045) via an inverse variance weighting method and other MR approaches. Higher vitamin B12 levels were robustly associated with decreased body fat percentage and its subtypes (all P < 0.05). Bidirectional analyses showed no reverse causation. Multivariable MR analyses and other sensitivity analyses showed directionally similar results.

Conclusions

There exist significant causal effects of vitamin B12 in the serum and Hcy in the blood on fat and musculoskeletal diseases, respectively. These findings may have an important insight into the pathogenesis of obesity and musculoskeletal diseases and other possible future therapies.

Homocysteine is associated with higher risks of ischemic stroke: A systematic review and meta-analysis

BACKGROUND

High levels of homocysteine (Hct) have been associated with great risks of ischemic stroke. However, some controversy still exists. We performed a systematic review and meta-analysis to compare the levels of Hct between patients with ischemic stroke and controls.

METHODS

We performed a systematic literature search for articles reporting Hct levels of patients with occurrence of ischemic stroke. We employed a random-effects inverse-variance weighted meta-analytical approach in order to pool standardized mean differences, with estimation of τ2 through the DerSimonian-Laird method.

RESULTS

The initial search yielded 1361 studies. After careful analysis of abstracts and full texts, the meta-analysis included data from 38 studies, which involved almost 16 000 stroke events. However, only 13 studies reported means and standard deviations for cases and controls, and therefore were used in the meta-analysis. Those studies presented data from 5002 patients with stroke and 4945 controls. Standardized mean difference was 1.67 (95% CI 1.00-2.25, P < 0.01), indicating that Hct levels were significantly larger in patients with ischemic stroke compared to controls. Between-study heterogeneity was very large (I2 = 99%), particularly because three studies showed significantly large mean differences.

CONCLUSION

This meta-analysis shows that patients with ischemic stroke have higher levels of Hct compared to controls. Whether this is a modifiable risk factor remains to be assessed through larger prospective cohorts.

Causal effects of homocysteine levels on the changes of bone mineral density and risk for bone fracture: A two-sample mendelian randomization study

BACKGROUND & AIMS

Observational studies have demonstrated the relations of homocysteine (HCY) with bone mineral density (BMD) and bone fracture risk, but yielding contradictory results. The present study was conducted to evaluate whether the genetically predicted plasma HCY levels were causally associated with the change of BMD and the risk of bone fracture.

METHODS

Genetic summary statistics were extracted from genome-wide association study (GWAS) meta-analysis of plasma HCY levels (n = 44,147), GWAS meta-analyses of measured forearm (FA), femoral neck (FN) and lumbar spine (LS) BMD (n = up to 32,735), UK Biobank estimated heel BMD (eBMD) (n = 426,824) and fracture (n = 426,795) GWAS data. Two Sample Mendelian Randomization (TSMR) analysis was performed to assess the causal effects of genetically determined plasma HCY on the BMD and bone fractures.

RESULTS

The MR analysis indicated that, genetically decreased plasma HCY was associated with the increased FA-BMD based on the inverse variance weighting (IVW) method (standard deviation [SD] = 0.348, 95% CI: 0.146 to 0.550, P = 7 × 10^-4). However, there were no significant associations of genetically decreased plasma HCY with FN-BMD, LS-BMD, eBMD and the risk for bone fracture (SD = -0.041, 95% CI: -0.189 to 0.106, P = 0.582; SD = -0.053, 95% CI: -0.238 to 0.131, P = 0.572; SD = -0.030, 95% CI: -0.090 to 0.030, P = 0.328, odds ratio [OR]: 1.03, 95% CI: 0.94 to 1.13, P = 0.562, respectively). Moreover, the results also found that genetically determined HCY increase was not correlated with the changes of BMD and the risk for bone fracture.

CONCLUSION

Our study revealed that genetically decreased plasma HCY was associated with increase of FA-BMD.

Plasma Sulfur Amino Acids and Risk of Cerebrovascular Diseases: A Nested Case-Control Study in the EPIC-Norfolk Cohort

BACKGROUND AND PURPOSE

B-vitamin supplements lower circulating concentrations of homocysteine and may reduce stroke incidence. Homocysteine concentrations are associated with the incidence of stroke but other sulfur-containing compounds in the related metabolic pathway have not yet been investigated for an association with incident cerebrovascular diseases.

METHODS

Nested within the EPIC (European Prospective Investigation Into Cancer and Nutrition)-Norfolk cohort, we established a case-control study with 480 incident cases of cerebrovascular diseases and 480 controls matched by age, sex, and year of baseline examination (1993-1997). Using baseline plasma samples, we assayed sulfur-containing compounds including methionine, homocysteine, cystathionine, cysteine, glutathione, and taurine with liquid chromatography-tandem mass spectrometry. We examined the association of concentrations of each of the compounds and the ratio of methionine to homocysteine (representing activity of one-carbon metabolism) with risk of incident cerebrovascular diseases, adjusted for potential confounders.

RESULTS

Plasma methionine and the methionine/homocysteine ratio were inversely associated with risk of cerebrovascular diseases, with odds ratios per 1 SD of 0.83 (95% CI, 0.72-0.96) and 0.82 (95% CI, 0.71-0.95), respectively. The association of methionine remained significant after adjustment for homocysteine. None of the other examined compounds was significantly associated with incident cerebrovascular diseases.

CONCLUSIONS

These findings suggest that greater availability of methionine, an essential amino acid, may play a role in the prevention of cerebrovascular diseases and explain the previously recognized link between elevated homocysteine and stroke. Further research is needed to determine causation and the potential of circulating methionine as a target in cerebrovascular disease prevention.

Correlation between plasma homocysteine and first myocardial infarction in young patients: Case-control study in Constanta County, Romania

An elevated level of total plasma homocysteine has been associated with a higher risk of atherosclerosis and coronary heart disease. The aim of our research was to study the relation between homocysteine and myocardial infarction (MI) in young patients. We conducted a case-control study in Constanţa County, Romania including 61 patients, divided in two groups. The first group, the MI group, consisted of 28 patients, male (67.9%) and female (32.1%) aged less than 45 years who were consecutively admitted to the Intensive Coronary Care Unit of the Emergency County Hospital of Constanţa from September 1, 2017 to August 31, 2018 (12 months), with an established diagnosis of first acute MI. The second group, the control group, included 33 patients, male (75.8%) and female (24.2%) aged less than 45 years, with cardiovascular risk factors and/or stable angina pectoris that were consecutively addressed for ambulatory cardiac evaluation at the Outpatient Clinic of Emergency County Hospital of Constanţa during the same period. Fasting plasma homocysteine was determined in both groups, within 24 h after MI onset, respectively after first cardiac exam in the controls. High homocysteine was statistically confirmed to be a risk factor in the study group, especially in association with smoking, chronic kidney disease (CKD), and to a lesser extent with diabetes mellitus (DM) and hypertension. Data analysis was performed using IBM SPSS Statistics 23. The procedures used included descriptive statistics, parametric statistical tests (Independent sample t-test), non-parametric statistical tests [Chi-square test of the association, with the evaluation of odds ratio (OR)]; the significance level used in the analysis (P-value) was 0.05. After adjusting for variables, our study results pointed out a strong association between plasma homocysteine and first acute MI among young patients, emphasising plasma homocysteine as a possible risk factor for myocardial infarction.

Correlation of Homocysteine Level and Age in Patients with Ischemic Stroke

Introduction

Hyperhomocysteinemia is associated with atherosclerosis, as it can be seen in inborn errors of methionine metabolism. Likewise, many studies have also reported more modest increases in serum homocysteine levels in other atherosclerotic disorders like cardiovascular disease and all types of stroke with a positive correlation with age. But overall literature is controversial. Therefore, this study is being conducted to further investigate the relationship between homocysteine ​​levels and age in patients, especially those with ischemic stroke.

Material and methods

This cross-sectional study is conducted at a major hospital in Karachi in which all patients with ischemic stroke, diagnosed within 24 hours on CT, and age 40-75 years of both genders were enrolled for six months. Other demographics were also noted like gender, smoking status, and comorbidities (diabetes mellitus [DM], hypertension [HTN]). The homocysteine level was also checked by collecting non-fasting blood. Vitamin B12 level was not checked. The age, weight, height, body mass index (BMI), and homocysteine level’s means and standard deviations and the gender, DM, hypertension, and smoking status frequencies and percentages were calculated. The correlation coefficient of homocysteine level and age was also calculated. Stratification was done to see the effects of gender, BMI, DM, and HTN on homocysteine levels by applying the chi-square test.

Results

The mean age of the patients was 55.60 ± 11.45 years. Gender distribution showed that 111 (62.40%) patients were male, and 67 (37.60%) patients were female. Diabetic, hypertensive, and smoking status of the patients was 58 (32.60%), 96 (53.90%), and 53 (29.80%), respectively. The mean homocysteine level was 14.61, with a standard deviation of 1.47. Pearson’s correlation test showed that there is no statistically significant correlation between homocysteine levels and age. But a significant linear relationship was found of homocysteine levels with DM and HTN. 

Conclusion

Further investigation of the relationship of homocysteine ​​levels with age, diabetes mellitus, and hypertension, and the role of homocysteine as a risk factor for ischemic stroke should be carried out on a larger scale to prove its accuracy. The benefits of screening for homocysteine ​​levels also need to be studied in the elderly, especially those with diabetes mellitus and hypertension, which can lead to timely prevention of strokes and ischemic heart disease with vitamin B supplements, and other appropriate interventions.

Modification of Platelet Count on the Association between Homocysteine and Blood Pressure: A Moderation Analysis in Chinese Hypertensive Patients

Background

Platelet consumption followed by homocysteine-induced endothelial injury suggests a crosstalk between platelet activation and homocysteine on hypertension. Platelet count has been found to modify the effect of folic acid on vascular health. However, whether platelet count could modify the contribution of homocysteine to blood pressure (BP) remains unclear.

Methods

Leveraging a community-based cross-sectional survey in 30,369 Chinese hypertensive patients (mean age 62 years, 52% female), we examined the moderation of platelet count on the association between serum homocysteine and BP by constructing hierarchical multiple regression models, adjusting for conventional risk factors. If adding the interaction term of homocysteine and platelet count could explain more variance in BP and the interaction is significant, then we believe that moderation is occurring.

Results

The association between serum homocysteine and diastolic BP was significantly stronger (β = 0.092 vs. 0.035, P = 0.004) in participants with low platelet count (<210 × 10⁹/L) than in those with high platelet count (≥210 × 10⁹/L). Adding the interaction term of homocysteine and platelet count additionally explained 0.05% of the variance in diastolic BP (P = 0.004) in participants with low platelet count (<210 × 10⁹/L) than in those with high platelet count (≥210 × 10⁹/L). Adding the interaction term of homocysteine and platelet count additionally explained 0.05% of the variance in diastolic BP (β = 0.092 vs. 0.035, P = 0.004) in participants with low platelet count (<210 × 10⁹/L) than in those with high platelet count (≥210 × 10⁹/L). Adding the interaction term of homocysteine and platelet count additionally explained 0.05% of the variance in diastolic BP (

Conclusions

The association between homocysteine and BP was significantly stronger in participants with low vs. high platelet count and was partially moderated by platelet count. These results indicate that platelet count may be useful in the identification of individuals who are most beneficial to reducing-homocysteine treatments but this usefullness still needs further investigation.

Metabolomics and Lipidomics of Ischemic Stroke

Ischemic stroke is a sudden loss of brain function due to the reduction of blood flow. Brain tissues cease to function with subsequent activation of the ischemic cascade. Metabolomics and lipidomics are modern disciplines that characterize the metabolites and lipid components of a biological system, respectively. Because the pathogenesis of ischemic stroke is heterogeneous and multifactorial, it is crucial to establish comprehensive metabolomic and lipidomic approaches to elucidate these alterations in this disease. Fortunately, metabolomic and lipidomic studies have the distinct advantages of identifying tissue/mechanism-specific biomarkers, predicting treatment and clinical outcome, and improving our understanding of the pathophysiologic basis of disease states. Therefore, recent applications of these analytical approaches in the early diagnosis of ischemic stroke were discussed. In addition, the emerging roles of metabolomics and lipidomics on ischemic stroke were summarized, in order to gain new insights into the mechanisms underlying ischemic stroke and in the search for novel metabolite biomarkers and their related pathways.

Astaxanthin Attenuates Homocysteine-Induced Cardiotoxicity in Vitro and in Vivo by Inhibiting Mitochondrial Dysfunction and Oxidative Damage

Homocysteine (Hcy) as an independent risk factor contributes to the occurrence and development of human cardiovascular diseases (CVD). Induction of oxidative stress and apoptosis was commonly accepted as the major mechanism in Hcy-induced cardiotoxicity. Astaxanthin (ATX) as one of the most powerful antioxidants exhibits novel cardioprotective potential against Hcy-induced endothelial dysfunction. However, the protective effect and mechanism of ATX against Hcy-induced cardiotoxicity in cardiomyocytes have not been elucidated yet. Herein, H9c2 rat cardiomyocytes and Hcy-injured animal model were employed in the present study. The MTT, flow cytometry analysis (FCM), TUNEL-DAPI and western blotting results all demonstrated that ATX significantly alleviated Hcy-induced cytotoxicity in H9c2 cells through inhibition of mitochondria-mediated apoptosis. The JC-1 and Mito-tracker staining both revealed that ATX pre-treatment blocked Hcy-induced mitochondrial dysfunction by regulating Bcl-2 family expression. Moreover, DCFH-DA and Mito-SOX staining showed that ATX effectively attenuated Hcy-induced oxidative damage via scavenging intracellular reactive oxygen species (ROS). Importantly, the ELISA and immunohistochemical results indicated that Hcy-induced cardiotoxicity in vivo was also significantly inhibited by ATX through inhibition of oxidative damage and apoptosis, and improvement of the angiogenesis. Taken together, our results demonstrated that ATX suppressed Hcy-induced cardiotoxicity in vitro and in vivo by inhibiting mitochondrial dysfunction and oxidative damage. Our findings validated the strategy of using ATX may be a highly efficient way to combat Hcy-mediated human CVD.