Elevated Total Homocysteine in All Participants and Plasma Vitamin B12 Concentrations in Women Are Associated With All-Cause and Cardiovascular Mortality in the Very Old: The Newcastle 85+ Study

Associations of total homocysteine and kidney function with all-cause and cause-specific mortality in hypertensive patients: a mediation and joint analysis

Plasma total homocysteine (tHcy) and kidney function are both associated with mortality risk, but the degree to which kidney function modifies the impact of tHcy on mortality remains unknown. This prospective cohort study included a total of 14,225 hypertensive adults. Cox proportional hazard regression was used to analyze the separate and combined association of tHcy and estimated glomerular filtration rate (eGFR) with all-cause and cause-specific mortality. Mediation analysis was conducted to explore the mediating effect of eGFR. During a median follow-up of 4.0 years, 805 deaths were identified, including 397 deaths from cardiovascular disease (CVD). There were significant, positive relationships of tHcy with all-cause mortality (per 5 μmol/L; HR: 1.09; 95% CI: 1.07, 1.11), CVD mortality (HR: 1.11; 95% CI: 1.08, 1.13), and non-CVD mortality (HR: 1.07; 95% CI: 1.04, 1.10). The proportions of eGFR mediating these relationships were 39.1%, 35.7%, and 49.7%, respectively. There were additive interactions between tHcy and eGFR. Compared with those with low tHcy (<15 μmol/L) and high eGFR (≥90 mL·min-1·1.73 m-2), participants with high tHcy (≥20 μmol/L) and low eGFR (<60 mL·min-1·1.73 m-2) had the highest risk of all-cause mortality (HR: 4.89; 95% CI: 3.81, 6.28), CVD mortality (HR: 5.80; 95% CI: 4.01, 8.40), and non-CVD mortality (HR: 4.25; 95% CI: 3.02, 5.97). In conclusion, among Chinese hypertensive adults, high tHcy and impaired kidney function were independently and jointly associated with higher risks of all-cause and cause-specific mortality. Importantly, kidney function explained most (nearly 40%) of the increased risk of mortality conferred by high tHcy.

Association of vitamin B12, folate, and homocysteine with COVID-19 severity and mortality: A systematic review and meta-analysis

Objective

We aimed to review the available evidence on the association between vitamin B12, folate, and homocysteine levels with worse outcomes among COVID-19 patients.

Methods

The search was carried out in ten databases simultaneously run on 10 May 2023, without language restrictions. We included cross-sectional, case-control, and cohort studies. The random-effects meta-analysis was performed using the Sidik-Jonkman method and corrected 95% confidence intervals using the truncated Knapp-Hartung standard errors. Standardized mean difference and 95% CI was used as the measure effect size.

Results

Thirteen articles were included in this review (n = 2134). Patients with COVID-19 who did not survive had the highest serum vitamin B12 values (SMD: 1.05; 95% CI: 0.31-1.78; p = 0.01, I2 = 91.22%). In contrast, low serum folate values were associated with patients with severe COVID-19 (SMD: -0.77; 95% CI: -1.35 to -0.19; p = 0.02, I2 = 59.09%). The remaining tested differences did not yield significant results.

Conclusion

Elevated serum levels of vitamin B12 were associated with higher mortality in patients with COVID-19. Severe cases of COVID-19 were associated with low serum folate levels. Future studies should incorporate a larger sample size.

Emerging Roles of Vitamin B12 in Aging and Inflammation

Vitamin B12 (cobalamin) is an essential nutrient for humans and animals. Metabolically active forms of B12-methylcobalamin and 5-deoxyadenosylcobalamin are cofactors for the enzymes methionine synthase and mitochondrial methylmalonyl-CoA mutase. Malfunction of these enzymes due to a scarcity of vitamin B12 leads to disturbance of one-carbon metabolism and impaired mitochondrial function. A significant fraction of the population (up to 20%) is deficient in vitamin B12, with a higher rate of deficiency among elderly people. B12 deficiency is associated with numerous hallmarks of aging at the cellular and organismal levels. Cellular senescence is characterized by high levels of DNA damage by metabolic abnormalities, increased mitochondrial dysfunction, and disturbance of epigenetic regulation. B12 deficiency could be responsible for or play a crucial part in these disorders. In this review, we focus on a comprehensive analysis of molecular mechanisms through which vitamin B12 influences aging. We review new data about how deficiency in vitamin B12 may accelerate cellular aging. Despite indications that vitamin B12 has an important role in health and healthy aging, knowledge of the influence of vitamin B12 on aging is still limited and requires further research.

Too Much of a Good Thing: The Association of Elevated Vitamin B12 Levels and Outcomes in Patients With Cancer Treated With Immunotherapy

Metabolic pathways may regulate responses to cancer immunotherapy (IO). Due to its immunomodulatory properties, we sought to examine the association between serum vitamin B12 (VitB12) and survival in individuals with cancer treated with immune checkpoint inhibitors, compared with biological and chemotherapy. We collected data on patients with advanced cancer initiating intravenous antineoplastic treatment and a concomitant VitB12 measurement (elevated: >820 ng/L), between January 2010 and January 2022. Patients on IO and other regimens (control) were compared using the Mann-Whitney test for continuous variables, χ 2 test or Fisher test for categorical variables, and multivariate Cox regression models assessed the effect of VitB12 on overall survival and progression-free survival, adjusting for confounders. Patient groups (control: n = 408; IO: n = 93) were balanced for the treatment line and VitB12 (elevated 29.9% vs 23.7%; mean 762.4 vs 687.6 ng/L). In multivariate analysis, overall survival in all patients was negatively associated with VitB12 [control: hazard ratio (HR): 1.4, 95% CI: 1.01-1.96, P = 0.04, false discovery rate (FDR): 0.069; IO: HR: 2.74 as sum of linear baseline and interaction effects, log scale], age (HR: 1.03, 95% CI: 1.02-1.04, P < 0.01), male sex (HR: 0.66, 95% CI: 0.50-0.88, P < 0.01), and neutrophil-to-lymphocyte ratio (HR: 1.05, 95% CI: 0.48-0.99, P = 0.01). However, VitB12 was significantly negatively associated with progression-free survival only in the IO group ( P < 0.001, FDR < 0.001, calculated HR: 8.34; biological treatment P = 0.08; FDR: 0.111; neutrophil-to-lymphocyte ratio, P = 0.07; FDR: 0.09). Taken together, elevated VitB12 was a negative predictor for outcomes on IO, independently of other known prognostic factors. Further research is needed to elucidate the immune-metabolic interplay and its interaction with the gut microbiome, as well as interventional strategies to enhance IO responses.

Nutrient intake and risk of multimorbidity: a prospective cohort study of 25,389 women

BACKGROUND

Multimorbidity is becoming an increasingly serious public health challenge in the aging population. The impact of nutrients on multimorbidity remains to be determined and was explored using data from a UK cohort study.

METHOD

Our research analysis is mainly based on the data collected by the United Kingdom Women's Cohort Study (UKWCS), which recruited 35,372 women aged 35-69 years at baseline (1995 to 1998), aiming to explore potential associations between diet and chronic diseases. Daily intakes of energy and nutrients were estimated using a validated 217-item food frequency questionnaire at recruitment. Multimorbidity was assessed using the Charlson comorbidity index (CCI) through electronic linkages to Hospital Episode Statistics up to March 2019. Cox's proportional hazards models were used to estimate associations between daily intakes of nutrients and risk of multimorbidity. Those associations were also analyzed in multinomial logistic regression as a sensitivity analysis. In addition, a stratified analysis was conducted with age 60 as the cutoff point.

RESULTS

Among the 25,389 participants, 7,799 subjects (30.7%) were confirmed with multimorbidity over a median follow-up of 22 years. Compared with the lowest quintile, the highest quintile of daily intakes of energy and protein were associated with 8% and 12% increased risk of multimorbidity respectively (HR 1.08 (95% CI 1.01, 1.16), p-linearity = 0.022 for energy; 1.12 (1.04, 1.21), p-linearity = 0.003 for protein). Higher quintiles of daily intakes of vitamin C and iron had a slightly lowered risk of multimorbidity, compared to the lowest quintile. A significantly higher risk of multimorbidity was found to be linearly associated with higher intake quintiles of vitamin B12 and vitamin D (p-linearity = 0.001 and 0.002, respectively) in Cox models, which became insignificant in multinomial logistic regression. There was some evidence of effect modification by age in intakes of iron and vitamin B1 associated with the risk of multimorbidity (p-interaction = 0.006 and 0.025, respectively).

CONCLUSIONS

Our findings highlight a link between nutrient intake and multimorbidity risk. However, there is uncertainty in our results, and more research is needed before definite conclusions can be reached.

The origin of vitamin B12 levels and risk of all-cause, cardiovascular and cancer specific mortality: A systematic review and dose-response meta-analysis

BACKGROUND

Vitamin B12 is essential to human but the implications of serum vitamin B12 level for mortality in clinical practice remain unclear. We conducted a systematic review and dose-response meta-analysis to quantify the relationship between vitamin B12 levels and the risk of all-cause, cardiovascular, and cancer mortality.

METHODS

Electronic databases of PubMed, Embase, and the Cochrane Library Central Register of Controlled Trials were searched from inception through May 2023. Two reviewers independently extracted individual study data and evaluated the risk of bias among the studies using the Newcastle‒Ottawa Scale. To examine a potential nonlinear relationship between the vitamin B12 levels and all-cause mortality, we performed a two-stage random effects dose‒response meta-analysis.

RESULTS

Twenty-two cohort studies (92,346 individuals with 10,704 all-cause deaths) were included. A linear trend dose-response analysis showed that each 100 pmol/L increase in serum vitamin B12 concentration was associated with a 4 % higher risk of all-cause mortality in the general population (adjusted HR 1.04, 95 % confidence interval CI 1.01 to 1.08; n = 8; P non-linearity = 0.11) and a 6 % higher risk for all-cause mortality in older adults (adjusted HR 1.06, 95 % CI 1.01 to 1.13; n = 4; P non-linearity = 0.78). Current evidence was mixed for the association between serum vitamin B12 concentration and cardiovascular mortality and was limited for cancer mortality. The meta-analysis of cohort studies showed a positive association between a high serum vitamin B12 concentration (>600 pmol/L) and all-cause mortality (adjusted HR 1.50, 95 % CI 1.29 to 1.74; n = 10; p < 0.01), CVD mortality (adjusted HR 2.04, 95 % CI 0.99 to 4.19; n = 2; p = 0.02), except cancer mortality (adjusted HR 1.56, 95 % CI 0.82 to 2.95; n = 3). Similarly, serum vitamin B12 concentrations (400-600 pmol/L) were associated with increased all-cause mortality (adjusted HR 1.34, 95 % CI 1.10 to 1.64; n = 9; p < 0.01).

CONCLUSIONS

Serum vitamin B12 concentration was positively associated with the risk of all-cause mortality, especially among older adults, with a linear increasing trend. These findings suggested the primary cause of elevated level of serum vitamin B12 concentration should be timely identified and effectively managed in clinical practice.

Association of B vitamin intake and total homocysteine levels with all-cause and cause-specific mortality in central obesity

OBJECTIVES

Future primary prevention strategies may benefit from understanding the connection between mortality in individuals with central obesity and modifiable lifestyle factors like dietary intake. This study sought to determine whether there was a separate relationship between folate, vitamin B6, and vitamin B12 intake and all-cause and cause-specific mortality in the US population with central obesity.

METHODS

The study analyzed data from the National Health and Nutrition Examination Survey between 1999 and 2016. Using the Cox proportional hazards model, the association between dietary intake of B vitamins and all-cause and cause-specific mortality was examined. A total of 7718 adults with central obesity were enrolled, with a mean age of 49.87 (SD = 0.25) y at baseline.

RESULTS

Folate intake was independently associated with a decreased incidence of all-cause mortality (adjusted hazard ratio = 0.71; 95% CI, 0.58-0.87). Furthermore, higher intake of vitamin B6 and vitamin B12 was inversely correlated with cardiovascular disease mortality (adjusted hazard ratio = 0.63; 95% CI, 0.40-0.98; and adjusted hazard ratio = 0.44; 95% CI, 0.29-0.65, respectively) and the finding reveal an interaction between homocysteine and vitamin B12 and folate on All-cause mortality CONCLUSIONS: The findings of this study suggest that vitamin B12 and folate intake may be protective factors in individuals with central obesity. It is important to consider both their total homocysteine level and body mass index in conjunction with these nutrients. Further research is needed to validate these findings.

The Impact of Clinical Factors, Vitamin B12 and Total Cholesterol on Severity of Anorexia Nervosa: A Multicentric Cross-Sectional Study

Severe forms of Anorexia Nervosa (AN) are characterized by medical complications, psychiatric comorbidity, and high mortality. This study investigated potential associations between clinical/biological factors and the severity of AN, measured by the Body Mass Index (BMI). Red and white blood cells, hemoglobin, platelets, iron, vitamins D and B12, folate, and total cholesterol were measured in a mixed sample of 78 inpatients and outpatients. Linear regressions and one-way analyses of variance (ANOVAs) were carried out to evaluate the relationship between BMI and clinical/biochemical variables. BMI was significantly lower in hospitalized patients (F = 4.662; p = 0.034) and in those under pharmacological treatment (F = 5.733; p = 0.019) or poly-therapy (F = 5.635; p = 0.021). Higher vitamin B12 (β = -0.556, p < 0.001), total cholesterol (β = -0.320, p = 0.027), and later age at onset (with a trend towards significance) (β = -0.376, p = 0.058) were associated with a lower BMI. Increased total cholesterol and vitamin B12, later age at onset, current pharmacological treatment, and poly-therapy might be distinctive in patients with a lower BMI. In clinical practice, these findings may contribute to the early identification of AN patients at higher risk of developing complicated or chronic forms of the disorder. Further studies on larger samples are needed to identify potential predictive factors of AN severity in the framework of precision medicine.

Low Levels of Serum Total Vitamin B12 Are Associated with Worse Metabolic Phenotype in a Large Population of Children, Adolescents and Young Adults, from Underweight to Severe Obesity

Vitamin B12 (or cobalamin) is an essential vitamin for DNA synthesis, fatty acid and protein metabolism as well as other metabolic pathways fundamental to the integrity of cells and tissues in humans. It is derived from the diet and mostly stored in the liver. Its deficiency has been associated with metabolic derangements, i.e., obesity, glucose intolerance, increased lipogenesis and metabolic dysfunction-associated steatotic liver disease (MASLD) and steatohepatitis (MASH). However, data with regard to body weight across the whole spectrum (from underweight to severe obesity) in children and young individuals are scarce. The present study aims to describe the association between serum total vitamin B12 and body mass index (BMI) ranging from underweight to severe obesity in a large population of children, adolescents and young adults. This study also investigates associations with visceral adiposity, glucose and lipid metabolism and liver dysfunction. A cross-sectional, single-centre study was conducted at the Paediatrics and Endocrinology units of the "Bambino Gesù Children Hospital", a tertiary referral institution for eating disorders. Clinical charts were reviewed and 601 patients aged from 5 to 25 years were enrolled in order to analyse anthropometric, auxological, clinical, biochemical and liver ultrasound data using robust statistical approaches. Analyses were adjusted for potential confounders. A reduction in serum total B12 levels was associated with a linear increase in body weight, as expressed by WHO BMI SDS (r = -0.31, p < 0.001, BCa 95% -0.38, -0.24). Lower B12 levels were associated with higher waist circumference but only in pubertal girls (r = -0.33, p = 0.008, BCa 95% -0.53, -0.11). Hepatic insulin resistance was higher in males with lower B12 levels (B = -0.003 (-0.007, -0.0001), p = 0.039), but not in females, whereas whole-body insulin resistance was unaffected. Serum lipid profiles (total, HDL and LDL cholesterol and triglycerides) were not influenced by serum cobalamin levels. However, lower cobalamin levels were associated with higher grading of ultrasound-scored hepatic steatosis (ptrend = 0.035). Lastly, both AST and ALT showed a significant and direct correlation with total B12 levels in underweight (r = 0.22 and 0.24, p = 0.002 and <0.001, respectively) and severely obese subjects (r = 0.24 and 0.32, p = 0.002 and <0.001). In conclusion lower vitamin B12 levels are associated with higher body weight, adiposity and with worse metabolic health in a large population of children, adolescents and young adults.

Associations between homocysteine, vitamin B12, and folate and the risk of all-cause mortality in American adults with stroke

Objective

Associations between plasma homocysteine (Hcy), vitamin B12, and folate and the risk of all-cause mortality are unclear. This study aimed to examine whether plasma Hcy, vitamin B12, and folate levels independently predict the risk of all-cause mortality in American adults with stroke.

Methods

Data from the United States National Health and Examination Survey (NHANES; 1999-2006) were used and linked with the latest (2019) National Death Index (NDI). Cox proportional hazards models and restricted cubic splines were used to estimate the hazard ratios (HR) and 95% confidence intervals (CI) of all-cause mortality for Hcy, folate, and B12 levels in adults with stroke. Sample weights were calculated to ensure the generalizability of the results.

Results

A total of 431 participants were included (average age: 64.8 years). During a median follow-up of 10.4 years, 316 deaths occurred. Hcy was positively associated with all-cause mortality in adults with stroke (HR, 1.053; 95% CI: 1.026-1.080). Stroke patients with plasma Hcy levels in the fourth quartile had a 1.631-fold higher risk of all-cause mortality (HR, 1.631; 95% CI: 1.160-2.291) than those in the first quartile. The association between plasma Hcy and all-cause mortality was strong significant in older patients (p for interaction = 0.020). Plasma folate and vitamin B12 concentrations were inversely correlated with Hcy concentrations [B-value (95% CI): -0.032 (-0.056- -0.008), -0.004 (-0.007- -0.002), respectively]. No significant associations were observed between folate, vitamin B12 levels, and all-cause mortality in adults with stroke.

Conclusion

Plasma Hcy levels were positively associated with all-cause mortality in older adults with stroke. Folate and vitamin B12 levels were inversely correlated with Hcy. Plasma Hcy may serve as a useful predictor in mortality risk assessment and targeted intervention in adults with stroke.

Etiology of Anemia and Risk Factors of Mortality among Hospitalized Patients: A Real-Life Retrospective Study in a Tertiary Center in Greece

Anemia is a prominent global health issue with a wide variety of causes and can be associated with decreased quality of life, increased hospitalization, and higher mortality, especially in older individuals. Therefore, studies further shedding light on the causes and the risk factors of this condition should be performed. The aim of the present study was to examine the causes of anemia in hospitalized patients in a tertiary hospital in Greece and identify risk factors related to higher mortality. In total, 846 adult patients with a diagnosis of anemia were admitted during the study period. The median age was 81 years, and 44.8% were male. The majority of patients had microcytic anemia, with the median mean corpuscular volume (MCV) being 76.3 fL and the median hemoglobin being 7.1 g/dL. Antiplatelets were used by 28.6% of patients, while 28.4% were using anticoagulants at the time of diagnosis. At least one unit of packed red blood cells (PRBCs) was transfused in 84.6% of patients, and a median of two PRBCs was used per patient. A gastroscopy was performed in 55%, and a colonoscopy was performed in 39.8% of patients in the present cohort. Anemia was considered to be multifactorial in almost half the cases, while the most commonly identified cause was iron deficiency anemia, more commonly with positive endoscopic findings. Mortality was relatively low, at 4.1%. Multivariate logistic regression analysis identified higher B12 levels and longer duration of hospital stay to be independently positively associated with mortality.

Associations of Serum Folate and Homocysteine Concentrations with All-Cause, Cardiovascular Disease, and Cancer Mortality in Men and Women in Korea: the Cardiovascular Disease Association Study

BACKGROUND

Evidence on the association of serum folate and homocysteine concentrations with risk of mortality in the general population is unclear.

OBJECTIVES

This study aimed to examine the associations of serum folate and homocysteine concentrations with all-cause, CVD, and cancer mortality risk in Korean men and women aged ≥40 y.

METHODS

In this population-based prospective cohort study, serum folate and homocysteine concentrations were measured in a subset of participants enrolled between 2005 and 2012. A total of 21,260 participants were linked to mortality data from the survey date to 31 December 2019. Cox proportional hazards models and restricted cubic splines were used to identify the associations of serum folate and homocysteine concentrations with mortality.

RESULTS

During a median follow-up of 12.3 y, 2501, 549, and 842 deaths were attributed to all-cause, CVD, and cancer, respectively. The prevalence of folate deficiency and hyperhomocysteinemia were higher in men than in women. In men, a nonlinear inverse association was observed between serum folate concentrations and all-cause mortality. Men in the third quartile of serum folate concentrations exhibited a lower risk of all-cause mortality (HR: 0.85; 95% CI: 0.73, 0.99) than those in the lowest quartile. Serum homocysteine concentration was positively associated with all-cause and CVD mortality. Men and women in the highest compared with those in the lowest serum homocysteine quartile showed a higher risk of CVD mortality (HR: 1.60; 95% CI: 1.07, 2.39; and HR: 1.79; 95% CI: 1.11, 2.89, respectively). Hyperhomocysteinemia combined with folate deficiency was associated with increased all-cause, CVD, and cancer-related mortality rates.

CONCLUSIONS

Higher serum homocysteine and lower serum folate concentrations were associated with an increased risk of all-cause, CVD, and cancer-related mortality in Korean adults. The finding of a nonlinear inverse relationship between serum folate concentration and mortality in men warrants further investigation.

Nonlinear associations of serum cobalamin with risk of all-cause and cardiovascular mortality in hypertensive adults

Our study aims to evaluate the associations between the serum cobalamin (vitamin B12) and related biomarkers with mortality in hypertensive adults. Data on serum cobalamin from the National Health and Nutrition Examination Survey (NHANES) 1999-2006 and 2011-2014 were included. Mortality status was linked to National Death Index mortality data through 31 December, 2019. Cox regression and restricted cubic spline (RCS) analyses were used to determine the hazard ratios (HRs) and 95% CIs for mortality risk. A total of 9934 hypertensive adults were included in the analysis (mean age, 58.1 ± 17.5 years; 4899 [49.3%] men). At 11.0 years of mean follow-up, 935 cardiovascular deaths and 3096 all-cause deaths were identified. Compared to the third quartiles, the first and fourth quartiles of serum cobalamin were associated with risk of cardiovascular mortality, with multivariable-adjusted HRs of 1.26 (1.05-1.53) and 1.40 (1.17-1.68). Similar results were observed in the relationship between serum cobalamin and all-cause mortality. These results were supported by the RCS analysis. The inflection points for the nonlinear associations of serum cobalamin with cardiovascular and all-cause mortality were 649.9 pg/mL and 577.2 pg/mL, respectively. In addition, compared with the second quartile of circulating methylmalonic acid (MMA, a cobalamin-deficiency marker), this association with the fourth quartile was evident for an increased rate of cardiovascular and all-cause mortality, with 111% (HR = 2.11, 1.71-2.61) and 73% (HR = 1.73, 1.55-1.93) increase. Findings suggest that both lower and higher serum cobalamin concentrations were associated with a higher risk of cardiovascular and all-cause mortality in hypertensive adults. This study was a prospective cohort study that included serum cobalamin data from 9934 hypertensive adults from the NHANES from 1999-2006 and 20011-2014. Findings suggested that both lower and higher serum cobalamin concentrations were associated with a higher risk of cardiovascular and all-cause mortality in hypertensive adults.

Homocysteine, Vitamin B12 and Folate Level: Possible Risk Factors in the Progression of Chronic Heart and Kidney Disorders

Cobalamin is an essential molecule for humans; it is exceptionally important for various body functions, including deoxyribonucleic acid synthesis and cellular energy production. Vegans are more vulnerable to vitamin B12 deficiency than natives with moderate consumption of animal dietary supplements or people with inadequate nutritional patterns. However, the long-term effects of sub-medical deficiency have not been thoroughly studied, but they may have a negative impact on the cardiovascular system, pregnancy outcomes, and vascular, renal, cognitive, bone, and eye health. Alongside the statin remedy, that is a powerful approach for CVD prevention. Another approach is related to the B nutrition substitution remedy with folic acid, and vitamins B6 and B12 are extensively practised nowadays. There is a tremendous interest in plasma homocysteine (tHcy) as a cardiovascular hazard factor. However, current research in the field of its prevention is more inclined toward confirming the benefit of tHcy-reducing remedy with vitamin B12. Thus, while folic acid fortification is primarily aimed at reducing neural-tube defects, it may also play a significant role in the primary prevention of CVD by lowering tHcy. Folate and B-vitamins play important roles in CVD prevention and nutrition policy implementation. Patients affected with Chronic Kidney Disease (CKD) or end-stage Stage Renal Disease (ESRD) experience a tremendous cardiovascular threat that may also further lead to death. As a result, routine monitoring of vitamin B12 levels is likely to be beneficial for the early detection and treatment of metabolic vitamin B12 deficiency, as well as the prevention of heart-related diseases.

Genetic susceptibility, homocysteine levels, and risk of all-cause and cause-specific mortality: A prospective cohort study

BACKGROUND

The associations of homocysteine (Hcy) and gene-Hcy interactions with the risk of all-cause and cause-specific mortality remain unclear.

METHODS

A total of 19,826 middle-aged and elderly Chinese adults were included from the Dongfeng-Tongji cohort in 2013-2014 and were followed-up to 31 December 2018. Cox regression was used to examine the association between Hcy and mortality. We selected 18 well-established Hcy-associated genetic variants to constructed the weighted genetic risk score (GRS) among 15,434 participants with genetic data, and interactions between genetic susceptibility and Hcy on mortality were assessed.

RESULTS

After multivariate adjustment, elevated serum Hcy levels were associated with higher risk of mortality from all-cause, CVD, coronary heart disease (CHD), stroke, and cancer. We also observed a significant interaction between GRS and Hcy on CHD mortality. Moreover, the rs7130284 and rs957140 on NOX4 modified the association between Hcy and mortality from CVD and CHD, and rs154657 on DPEP1 modified the association between Hcy and CHD mortality.

CONCLUSIONS

Elevated Hcy levels were associated with increased risk of all-cause and cause-specific mortality among middle-aged and elderly Chinese. Hcy-related genetic variants on NOX4 and DPEP1 might modify the associations of Hcy with CVD mortality or CHD mortality.

Increased serum methylmalonic acid levels were associated with the presence of cardiovascular diseases

Background

Functional vitamin B12 deficiency is common in cardiovascular diseases (CVDs), such as heart failure and myocardial infarction. Methylmalonic acid (MMA) is a specific and sensitive marker of vitamin B12 deficiency. However, there are scarce data in regard to the relationship between MMA and CVDs.

Materials and methods

In this cross-sectional study, we analyzed data of 5,313 adult participants of the National Health and Nutrition Examination Survey (NHANES) 2013-2014. Associations between MMA and other variables were assessed with linear regression models. Univariable and multivariable logistic regression models were employed to explore the association between MMA and CVDs.

Results

The weighted prevalence of CVDs was 8.8% in the general population of the USA. Higher MMA levels were found in participants with CVDs (p < 0.001). Linear regression models revealed positive associations between serum MMA level and age (p < 0.001), glycohemoglobin (p = 0.023), fasting glucose (p = 0.044), mean cell volume (p = 0.038), and hypertension (p = 0.003). In the multivariable logistic model adjusting for age, gender, ethnicity, smoking, hypertension, glycohemoglobin, body mass index (BMI), low-density lipoprotein-cholesterol (LDL-C), renal dysfunction and vitamin B12, serum MMA (adjusted odds ratio, 3.08; 95% confidence interval: 1.63-5.81, p = 0.002, per ln nmol/L increment) was associated with CVDs.

Conclusion

Our study demonstrated that elevated serum MMA levels were independently associated with the presence of CVDs and may be used to predict the occurrence of CVDs.

Association between hyperhomocysteinaemia and the risk of all-cause and cause-specific mortality among adults in the USA

Hyperhomocysteinaemia (HHcy) is associated with all-cause mortality in some disease states. However, the correlation between HHcy and the risk of mortality in the general population has rarely been researched. We aimed to evaluate the association between HHcy and all-cause and cause-specific mortality among adults in the USA. This study analysed data from the National Health and Nutrition Examination Survey database (1999-2002 survey cycle). A multivariable Cox regression model was built to evaluate the correlation between HHcy and all-cause and cause-specific mortality. Smooth curve fitting was used to analyse their dose-dependent relationship. A total of 8442 adults aged 18-70 years were included in this study. After a median follow-up period of 14·7 years, 1007 (11·9 %) deaths occurred including 197 CVD-related deaths, 255 cancer-related deaths and fifty-eight respiratory disease deaths. The participants with HHcy had a 93 % increased risk of all-cause mortality (hazard ratio (HR) 1·93; 95 % CI (1·48, 2·51)), 160 % increased risk of CVD mortality (HR 2·60; 95 % CI (1·52, 4·45)) and 82 % increased risk of cancer mortality (HR 1·82; 95 % CI (1·03, 3·21)) compared with those without HHcy. For unmeasured confounding, E-value analysis proved to be robust. In conclusion, HHcy was associated with high risk of all-cause and cause-specific (CVD, cancer) mortality among adults aged below 70 years.

The Controversial Role of HCY and Vitamin B Deficiency in Cardiovascular Diseases

Plasma homocysteine (HCY) is an established risk factor for cardiovascular disease CVD and stroke. However, more than two decades of intensive research activities has failed to demonstrate that Hcy lowering through B-vitamin supplementation results in a reduction in CVD risk. Therefore, doubts about a causal involvement of hyperhomocysteinemia (HHcy) and B-vitamin deficiencies in atherosclerosis persist. Existing evidence indicates that HHcy increases oxidative stress, causes endoplasmatic reticulum (ER) stress, alters DNA methylation and, thus, modulates the expression of numerous pathogenic and protective genes. Moreover, Hcy can bind directly to proteins, which can change protein function and impact the intracellular redox state. As most mechanistic evidence is derived from experimental studies with rather artificial settings, the relevance of these results in humans remains a matter of debate. Recently, it has also been proposed that HHcy and B-vitamin deficiencies may promote CVD through accelerated telomere shortening and telomere dysfunction. This review provides a critical overview of the existing literature regarding the role of HHcy and B-vitamin deficiencies in CVD. At present, the CVD risk associated with HHcy and B vitamins is not effectively actionable. Therefore, routine screening for HHcy in CVD patients is of limited value. However, B-vitamin depletion is rather common among the elderly, and in such cases existing deficiencies should be corrected. While Hcy-lowering with high doses of B vitamins has no beneficial effects in secondary CVD prevention, the role of Hcy in primary disease prevention is insufficiently studied. Therefore, more intervention and experimental studies are needed to address existing gaps in knowledge.

Associations of Serum Folate and Vitamin B12 Levels With Cardiovascular Disease Mortality Among Patients With Type 2 Diabetes

IMPORTANCE

The associations of serum folate and vitamin B12 levels with cardiovascular outcomes among patients with type 2 diabetes (T2D) remain unclear.

OBJECTIVE

To investigate the associations of serum folate and vitamin B12 levels with risk of cardiovascular disease (CVD) mortality among individuals with T2D.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study included 8067 patients with T2D who participated in the National Health and Nutrition Examination Survey (NHANES) from 1999 through 2014 and NHANES III (1988-1994). American Diabetes Association criteria were used to define T2D. Data were analyzed between October 1, 2020, and April 1, 2021.

EXPOSURES

Serum folate and vitamin B12 levels.

MAIN OUTCOMES AND MEASURES

Multivariable Cox proportional hazards regression models were used to compute hazard ratios and 95% CIs for the associations of serum folate and vitamin B12 levels with risks of CVD and all-cause mortality. Two multivariable models were constructed. Restricted cubic spline analyses were used to examine the nonlinear association of serum folate levels and vitamin B12 levels with CVD mortality, and nonlinearity was assessed using the likelihood ratio test.

RESULTS

This cohort study included data from 7700 participants in the folate analysis (mean [SE] age, 57.8 [0.3] years; 3882 men [weighted, 50.5%]; median serum folate level, 12.1 ng/mL [IQR, 7.1-19.5 ng/mL]) and 4860 participants for the vitamin B12 analysis (mean [SE] age, 57.8 [0.3] years; 2390 men [weighted, 50.7%]; median serum vitamin B12 level, 506.1 pg/mL [IQR, 369.1-703.5 pg/mL]). During 72 031 person-years of follow-up, 799 CVD deaths were documented for the folate analysis, and during 43 855 person-years of follow-up, 467 CVD deaths were reported for the vitamin B12 analysis. Nonlinear associations were observed for serum levels of folate (P = .04 for nonlinearity) and vitamin B12 (P = .04 for nonlinearity) with risk of CVD mortality among patients with T2D. Compared with participants in the second quartile of serum folate levels (7.1-12.1 ng/mL), the hazard ratios for CVD mortality were 1.43 (95% CI, 1.04-1.98) for participants in the lowest serum folate level quartile (<7.1 ng/mL) and 1.03 (95% CI, 0.74-1.44) for participants in the highest quartile (≥19.5 ng/mL). In addition, compared with participants in the second quartile of serum vitamin B12 levels (369.1-506.0 pg/mL), the hazard ratios for CVD mortality were 1.74 (95% CI, 1.20-2.52) for participants in the lowest quartile (<369.1 pg/mL) and 2.32 (95% CI, 1.60-3.35) for participants in the highest quartile (≥703.5 pg/mL). Similar patterns of association were observed for all-cause mortality (nonlinearity: P = .01 for folate and P = .02 for vitamin B12).

CONCLUSIONS AND RELEVANCE

This cohort study found that both low and high serum levels of vitamin B12 as well as low serum levels of folate were significantly associated with higher risk of CVD mortality among individuals with T2D.

Homocysteine, Folic Acid, Cyanocobalamin, and Frailty in Older People: Findings From the “Invece. Ab” Study

Frailty is an important age-related syndrome associated with several adverse health outcomes. Its biological basis is undefined. Raised plasma homocysteine (HOcy) is an established risk factor for cardiovascular disease, dementia, cognitive impairment, and mortality, but little is known about the possible role of plasma HOcy, cyanocobalamin (B12), and folate (FO levels in the development of frailty. Our first aim was to explore the possible association between frailty and plasma concentrations of HOcy, FO, and B12 in a cohort of community-dwelling older people. The second was to assess the influence of these metabolic factors on six-year incidence of frailty in the 875 individuals eligible for inclusion in this study (those with a full follow-up dataset). This research is based on data from three waves – 2012 (herein taken as baseline), 2014, and 2018 – of a longitudinal study (InveCe.Ab) in which non-frail men and women born between 1935 and 1939 underwent multidimensional assessments. Frailty was estimated using a deficit accumulation-based frailty index (FI). HOcy concentration was significantly positively correlated with FI at all timepoints, while B12 and FO levels were not. Plasma concentration of HOcy emerged as a predictor of six-year cumulative incidence of frailty, independent of age, sex, and education, while B12 and FO levels showed no relationship with frailty incidence. Individuals with plasma HOcy in the top quintile showed five months less frailty-free survival (HR 1.487; 95% CI: 1.063–2.078), regardless of age, sex, and education. These results demonstrate that higher HOcy is a risk factor for frailty onset in older adults.

Plasma Vitamin B12 and Folate Alter the Association of Blood Lead and Cadmium and Total Urinary Arsenic Levels with Chronic Kidney Disease in a Taiwanese Population

Heavy metals causing chronic nephrotoxicity may play a key role in the pathogenesis of chronic kidney disease (CKD). This study hypothesized that plasma folate and vitamin B₁₂ would modify the association of CKD with total urinary arsenic and blood lead and cadmium levels. We recruited 220 patients with CKD who had an estimated glomerular filtration rate of <60 mL/min/1.73 m² for ≥3 consecutive months and 438 sex- and age-matched controls. We performed inductively coupled plasma mass spectrometry to measure blood cadmium and lead levels. The urinary arsenic level was determined using a high-performance liquid chromatography–hydride generator–atomic absorption spectrometry. Plasma vitamin B₁₂ and folate levels were measured through the SimulTRAC-SNB radioassay. Compared with patients with plasma vitamin B₁₂ ≤ 6.27 pg/mL, the odds ratio (OR) and 95% confidence interval of CKD for patients with plasma vitamin B₁₂ > 9.54 pg/mL was 2.02 (1.15–3.55). However, no association was observed between plasma folate concentration and CKD. A high level of plasma vitamin B₁₂ combined with high levels of blood lead and cadmium level and total urinary arsenic tended to increase the OR of CKD in a dose-response manner, but the interactions were nonsignificant. This is the first study to demonstrate that patients with high plasma vitamin B₁₂ level exhibit increased OR of CKD related to high levels of blood cadmium and lead and total urinary arsenic.

Association between serum vitamin B12 and risk of all-cause mortality in elderly adults: a prospective cohort study

BACKGROUND AND PURPOSE

Results from previous studies that linking vitamin B12 to risk of chronic diseases or mortality are inconsistent. We hereby explore the association between serum concentration of vitamin B12 and all-cause mortality risk in elderly adults.

METHODS

Participants aged over 65 years in the Chinese Longitudinal Healthy Longevity Survey were included in present prospective cohort study. Serum vitamin B12 was assessed at the 2011-2012 and 2014 wave, respectively. Participants were divided into three groups based on two cut-off points - 10th and 90th percentiles of vitamin B12 concentrations - in the whole population. Cox regression model was used to calculate the hazard ratio (HR) and 95 % confidence intervals (95 % CIs), and restricted cubic spline function was further modelled to investigate their dose-response associations.

RESULTS

Among 2,086 participants [mean ± SD: 87.74 ± 11.24 years, 908 (43.53 %) males], 943 (45.21 %) died during an average follow-up of 3.34 (SD: 1.63) years. Comparing with participants with middle concentration of serum vitamin B12, participants with high concentration had an increased risk of all-cause mortality [HR (95 %CIs): 1.30 (1.03-1.64)], whereas participants with low concentration had an insignificantly decreased risk of all-cause mortality (0.96, 0.76-1.20). The positive association between high concentration of serum vitamin B12 and all-cause mortality was also observed among the male and in a series of sensitivity analyses. In the dose-response analysis, a J-shape pattern was observed, but the non-linear association was only significant in males (P_{non-linearity} = 0.0351).

CONCLUSIONS

High concentration of serum vitamin B12 was associated with an increased risk of all-cause mortality in a J-shaped pattern. The precise mechanisms underlying the association remain to be explored.

High Serum Folate Concentrations Are Associated with Decreased Risk of Mortality among Japanese Adults

BACKGROUND

Folate and vitamin B-12 are essential nutrients for normal cell growth and replication, but the association of serum folate and vitamin B-12 concentrations with mortality risk remains uncertain.

OBJECTIVE

This study was performed to investigate the associations of serum folate and vitamin B-12 concentrations with mortality risk and test whether the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism modifies these associations.

METHODS

A total of 3050 Japanese community residents aged ≥40 y were prospectively followed-up for mortality between 2002 and 2012. Cox proportional hazards models and restricted cubic splines were used to estimate HRs and 95% CIs of mortality.

RESULTS

During a median follow-up period of 10.2 y, 336 participants died. Higher serum folate concentrations were associated with lower risks of all-cause mortality [multivariable-adjusted HR: 0.73; 95% CI: 0.56, 0.96 for the second tertile (8.8-12.2 nmol/L; median 10.4 nmol/L) and HR: 0.61; 95% CI: 0.46, 0.80 for the third tertile (≥12.5 nmol/L; median 15.6 nmol/L) serum folate concentrations compared with the first tertile (≤8.6 nmol/L; median 7.0 nmol/L)]. This association remained significant in all sensitivity analyses. Spline analyses showed a steady decline in all-cause mortality risk with increasing serum folate concentrations up to 20-25 nmol/L. This association persisted regardless of the MTHFR C677T genotypes. For serum vitamin B-12, the multivariable-adjusted HR of 1.32 (95% CI: 0.97, 1.79) of all-cause mortality was marginally significantly greater in the first tertile compared with the second tertile. This association was attenuated and nonsignificant after the exclusion of participants with a history of cardiovascular disease or cancer, or participants aged ≥85 y at baseline, or deaths in the first 3 y of follow-up.

CONCLUSIONS

Serum folate concentrations were inversely associated with the risk of all-cause mortality in Japanese adults. Serum vitamin B-12 concentrations were not consistently associated with all-cause mortality risk after accounting for reverse-causation bias.

Homocysteine and C-Reactive Protein Levels Are Associated With Frailty in Older Spaniards: The Toledo Study for Healthy Aging

High-sensitivity C-reactive protein (hsCRP) and homocysteine (Hcy) are inflammation markers but are also related to cardiovascular diseases, disability, or higher risk of death. Although inflammation is considered to be associated with frailty, data regarding the association between hsCRP or Hcy and frailty are controversial or scarce, especially with respect to their association with prefrailty. Thus, our objective was to study the association of hsCRP and Hcy with prefrailty and frailty in 1,211 Spanish men and women aged 65-98 years from the Toledo Study for Healthy Aging (TSHA) cohort, classified according to Fried's criteria. Hcy was independently associated with frailty (odds ratio [OR] = 1.06; 95% confidence interval [CI]: 1.01-1.12), whereas hsCRP was independently associated with both prefrailty (OR = 1.03; 95% CI: 1.01-1.06) and frailty (OR = 1.07; 95% CI: 1.02-1.12). Furthermore, both markers were positively correlated with the number of Fried's criteria that were met and were independently associated with the criteria of exhaustion (Hcy: OR = 1.03, 95% CI: 1.00-1.06), weakness (hsCRP: OR = 1.03, 95% CI: 1.01-1.05), and low physical activity (hsCRP: OR = 1.04, 95% CI: 1.02-1.06). Thus, our results highlight the importance of inflammation in age-related physical decline and, in particular, its association with fatigue, low strength, and decreased physical activity.

Update on Safety Profiles of Vitamins B1, B6, and B12: A Narrative Review

The neurotropic B vitamins B1 (thiamine), B6 (pyridoxine), and B12 (cobalamin) are essential for proper functioning of the nervous system. Deficiencies may induce neurological disorders like peripheral neuropathy (PN) and mainly occur in vulnerable populations (eg, elderly, diabetics, alcoholics). As epidemiologic cohort studies raised safety concerns about vitamin B6/B12 intake being potentially associated with increased risks of hip fracture (HF) and lung cancer (LC), we explored these aspects and performed comprehensive literature searches. However, we suggest not to neglect actual high-risk factors (eg, smoking in LC, higher age in HF) by focusing on individual nutrients, but to examine the complex interaction of numerous factors involved in disease development. Because it warrants continued consideration, we also provide an update on neurotoxicity associated with vitamin B6. We consider that neurological side effects due to vitamin B6 intake are rare and only occur with high daily doses and/or longer treatment duration. The benefit-risk ratio of high-dose treatment with neurotropic B vitamins in indications like PN is therefore considered advantageous, particularly if dosing recommendations are followed and serum levels monitored.

Relationship between serum B12 concentrations and mortality: experience in NHANES

BACKGROUND

There is conflicting evidence in the literature on the association between (elevated) serum B12 concentrations and subsequent disease or mortality. We evaluated in the NHANES general population the association of serum B12 concentrations as well as vitamin B12 supplement intake with all-cause, cardiovascular, and cancer-related mortality, while taking into account demographic and lifestyle factors and significant other diseases which are known to be associated with poorer outcome.

METHODS

The main outcomes of our study were all-cause mortality, cardiovascular mortality, and cancer-related mortality. Mortality status and cause of death were determined by NHANES-linked National Death Index public access files through December 31, 2015. The association of serum B12 concentrations and vitamin B12 supplement intake with mortality was assessed with Cox proportional hazard (PH) models, with adjustment for a number of relevant demographic and lifestyle factors and comorbidity.

RESULTS

The final study population of 24,262 participants had a mean age of 48 (SD 19) years; 50.1% were males. The median follow-up duration was 109 months (range 1-201 months). On the census day of December 31, 2015, 3023 participants were determined as deceased (12.5%). The fully adjusted Cox PH model indicated that low serum B12 concentrations < 140 pmol/l were associated with a small increase in all-cause (hazard ratio, HR 1.39, 95% CI 1.08-1.78, p = 0.011) and cardiovascular (HR 1.64, 95% CI 1.08-2.47, p = 0.020) mortality. Similarly, high serum B12 concentrations > 700 pmol/l were associated with an increase in cardiovascular mortality only (HR 1.45, 95% CI 1.01-2.06, p = 0.042). Participants with a diagnosis of hypertension, dyslipidemia, CVD, and cancer more frequently used vitamin B12-containing supplements than those without these diagnoses. We could not demonstrate an association between vitamin B12 supplement intake and mortality, when adjusted for comorbidity.

CONCLUSIONS

In the general population of NHANES, low serum B12 concentrations were associated with a moderate increase in all-cause mortality. There was a small but significant increase in cardiovascular mortality in the groups with low or high serum B12. High intake of vitamin B12 in the form of supplements was not associated with any adverse effect on mortality and therefore can be regarded as safe.

Low Vitamin B12 and Lipid Metabolism: Evidence from Pre-Clinical and Clinical Studies

Obesity is a worldwide epidemic responsible for 5% of global mortality. The risks of developing other key metabolic disorders like diabetes, hypertension and cardiovascular diseases (CVDs) are increased by obesity, causing a great public health concern. A series of epidemiological studies and animal models have demonstrated a relationship between the importance of vitamin B12 (B12) and various components of metabolic syndrome. High prevalence of low B12 levels has been shown in European (27%) and South Indian (32%) patients with type 2 diabetes (T2D). A longitudinal prospective study in pregnant women has shown that low B12 status could independently predict the development of T2D five years after delivery. Likewise, children born to mothers with low B12 levels may have excess fat accumulation which in turn can result in higher insulin resistance and risk of T2D and/or CVD in adulthood. However, the independent role of B12 on lipid metabolism, a key risk factor for cardiometabolic disorders, has not been explored to a larger extent. In this review, we provide evidence from pre-clinical and clinical studies on the role of low B12 status on lipid metabolism and insights on the possible epigenetic mechanisms including DNA methylation, micro-RNA and histone modifications. Although, there are only a few association studies of B12 on epigenetic mechanisms, novel approaches to understand the functional changes caused by these epigenetic markers are warranted.

Homocysteine and the Risk of Cardiovascular Events and All-Cause Death in Elderly Population: A Community-Based Prospective Cohort Study

Background

The association between homocysteine and cardiovascular diseases (CVD) and all-cause death was inconclusive. A community-based prospective cohort study was carried out in Beijing to evaluate this association in elderly population for more effective clinical prediction and primary prevention of CVD.

Patients and Methods

Participants were randomly selected from Beijing, China. Questionnaire survey, physical examinations, and laboratory tests were carried out to collect baseline information and investigate clinical characteristics. Each participant was predetermined to be followed by 5 years. CVD events and death were collected as primary variables. A Cox regression analysis was performed to assess the risk of CVD events, CVD death, and all-cause death contributed by homocysteine as well as some other risk factors.

Results

A total of 1257 participants with an average age of 69.16 years were enrolled in this study. After adjusting for confounders, the hazard ratios (HRs) and 95% confidence intervals of CVD event, CVD death, and all-cause death caused by intermediate-to-severe hyperhomocysteinemia as compared with normal homocysteine levels were 1.68 (95% CI 1.06–2.67), 1.97 (95% CI 0.95–4.29) and 2.02 (95% CI 1.26–3.24), respectively. Intermediate-to-severe hyperhomocysteinemia increased the risks of CVD event (HR 2.07, 95% CI 1.01–4.26) and all-cause death (HR 3.08, 95% CI 1.56–6.07) among male participants. However, the positive association was not statistically significant among female participants (HR 1.59, 95% CI 0.83–3.04 for CVD event and HR 0.90, 95% CI 0.52–6.07 for all-cause death). Every 5μmol/L increment in homocysteine concentration was shown to be associated with a 4% (HR 1.04, 95% CI 1.01–1.07) and 5% (HR 1.05, 95% CI 1.01–1.07) higher risk of CVD events and all-cause death in all participants. There was no significant association between moderate hyperhomocysteinemia and the risk of the CVD events and all-cause death.

Conclusion

Intermediate-to-severe hyperhomocysteinemia was significantly associated with CVD events and all-cause death in elderly population without a history of ischemia or congestive heart failure (CHF). The positive association was pronounced among males.

Serum Vitamin B12, and Related MTRR and Cubilin Genotypes, Predict Neural Outcomes across the AD Spectrum

Epidemiological studies show mixed findings for serum vitamin B12 and both cognitive and regional volume outcomes. No studies to date have comprehensively examined, in non-supplemented individuals, serum B12 level associations with neurodegeneration, hypometabolism, and cognition across the Alzheimer's disease (AD) spectrum. Serum vitamin B12 was assayed from the Alzheimer's Disease Neuroimaging Initiative (ADNI) and the Australian Imaging, Biomarker & Lifestyle Flagship Study of Ageing (AIBL). Voxel-wise analyses regressed B12 levels against regional gray matter (GM) volume and glucose metabolism (p<.05, family-wise corrected). For ADNI GM, there were 39 cognitively normal (CN), 73 mild cognitive impairment (MCI), and 31 AD participants. For AIBL GM, there were 311 CN, 59 MCI, and 31 AD participants. Covariates were age, sex, baseline diagnosis, APOE4 status, and Body Mass Index (BMI). In ADNI, higher B12 was negatively associated with GM in the right precuneus and bilateral frontal gyri. When diagnostic groups were examined separately, only participants with MCI or above an established cutoff for CSF total tau showed such associations. In AIBL, higher B12 was associated with more grey matter in the right amygdala and right superior temporal pole, which largely seemed to be driven by CN participants that constituted most of the sample. Our results suggest that B12 may show different patterns of association based on clinical status and, for ADNI, AD CSF biomarkers. Accounting for these factors may clarify the relationship between B12 with neural outcomes in late-life.

Effect of Moxibustion on Hyperhomocysteinemia and Oxidative Stress Induced by High-Methionine Diet

Objective

The aim of this study was to assess the effects of moxibustion on the animal model of oxidative stress and cardiovascular injury induced by high-methionine diet (2% methionine and 3.5% fat on the basis of ordinary maintenance feed) during 12 weeks.

Methods

53 mice were divided into four groups: mice in the Control group (n = 8), mice in the Met group (n = 8), mice in the Met group (n = 8), mice in the Met group (n = 8), mice in the Met group (

Results

Compared with the Met group, our results indicated that through moxibustion intervention, the content of serum Hcy and its intermediate metabolite SAH can be reduced to a certain extent, and SOD, HO-1, and ox-LDL can be increased.

Conclusion

This study showed moxibustion's ability to enhance the body's antioxidation and protect vascular endothelial function, thus playing an early role in the prevention and treatment of atherosclerosis.

Association of Plasma Concentration of Vitamin B12 With All-Cause Mortality in the General Population in the Netherlands

IMPORTANCE

Higher plasma concentrations of vitamin B12 have been associated with mortality in elderly and hospitalized populations, including patients with chronic kidney disease, but the association of plasma concentrations of vitamin B12 with mortality in the general population remains unclear.

OBJECTIVE

To investigate the association of plasma concentrations of vitamin B12 with all-cause mortality.

DESIGN, SETTING, AND PARTICIPANTS

This longitudinal cohort study used post hoc analysis to examine data from participants of the Prevention of Renal and Vascular End-stage Disease Study in Groningen, the Netherlands. Participants included individuals who completed the second screening visit beginning January 1, 2001, excluding those who were missing values of vitamin B12 plasma concentrations or used vitamin B12 supplementation. Follow-up time was defined between the beginning of the second screening round to end of follow-up on January 1, 2011. Data analysis was conducted from October 2, 2018, to February 22, 2019.

EXPOSURES

Plasma vitamin B12 concentration level.

MAIN OUTCOMES AND MEASURES

Death as recorded by the Central Bureau of Statistics of Groningen, the Netherlands.

RESULTS

A total of 5571 participants (mean [SD] age, 53.5 [12.0] years; 2830 [50.8%] men) were included in analyses. Median (interquartile range) plasma concentration of vitamin B12 was 394.42 (310.38-497.42) pg/mL. During the median (interquartile range) of 8.2 (7.7-8.9) years of follow-up, 226 participants (4.1%) died. According to quartiles of the distribution of plasma vitamin B12 concentration levels, mortality rates were 33.8 deaths per 10 000 person-years for the quartile with the lowest plasma concentration of vitamin B12 and 65.7 deaths per 10 000 person-years for the quartile with the highest plasma concentration of vitamin B12. After adjustment for multiple clinical and laboratory variables, Cox regression analyses found a significant association between higher vitamin B12 plasma concentration level and increased risk of all-cause mortality (hazard ratio per 1-SD increase, 1.25 [95% CI, 1.06-1.47]; P = .006).

CONCLUSIONS AND RELEVANCE

These findings suggest that higher levels of plasma concentrations of vitamin B12 were associated with increased risk of all-cause mortality after adjusting for age, sex, renal function, and other clinical and laboratory variables. The mechanisms underlying this association remain to be established.

Deficiência de vitamina B12 e fatores associados em idosos institucionalizados

Resumo Objetivo Avaliar a frequência de deficiência de vitamina B12 e fatores associados em idosos institucionalizados. Método Analisamos 65 idosos, com idade média de 80±9 anos (61-113), de uma instituição geriátrica filantrópica de longa permanência. A dosagem sérica de vitamina B12 foi analisada e classificada em: normal (≥299 pg/mL), limítrofe (200-298 pg/mL) e deficiência (<200 pg/mL). Foi analisada a associação com tempo de permanência na instituição, declínio cognitivo e funcional, uso regular de biguanidas e inibidores de bomba de prótons, considerados fatores de risco para hipovitaminose B12, utilizando os testes de análise bivariada (paramétrica e não paramétrica) e regressão de Poisson. Resultados A deficiência de vitamina B12 estava presente em 21,5% e valores limítrofes em 32,3% da amostra. Dentre os idosos, 52,9% apresentavam demência de causas diversas, 49,2% hipertensão arterial, 29,2% com anemia (21,5% normocítica, 4,6% microcítica e 3,1% macrocítica), 18,5% diabéticos; 27,7% faziam uso de polifarmácia, com 12,3% em uso de metformina e 16,9% com inibidores de bomba de prótons. No modelo multivariado não houve associação entre a deficiência de vitamina B12 com as variáveis estudadas. Conclusão Observamos uma frequência importante de valores limítrofes e baixos de vitamina B12 nos pacientes dessa instuição geriátrica de cuidados permanentes, porém sem associação com os fatores de risco para sua deficiência estudado, o que torna importante a inclusão da dosagem sérica dessa vitamina na rotina de exames laboratoriais desse grupo.

Telomere length, vitamin B12 and mortality in persons undergoing coronary angiography: the Ludwigshafen risk and cardiovascular health study

Background: Vitamin B12 (B12) deficiency and excess are associated with increased risk of age-related-diseases and mortality. It has been suggested that high- and low-B12 concentrations link to increased mortality through accelerated genomic aging and inflammation. Evidence to support this is limited.

Results: B12 was associated with all-cause-mortality, RTL and hsCRP in a non-linear fashion. The association between B12 and mortality was not independent, as it lost significance after adjustment for potential confounders. In the lowest-(LB12) and highest-(HB12) quartiles of B12 mortality was higher than in the mid-range (HR:LB12:1.23;CI95%:1.06-1.43; HR:HB12:1.24;CI95%:1.06-1.44). We divided subjects with LB12 in quartiles of their RTL. Those with the longest-telomeres had a lower mortality-rate (HR:0.57;95%CI:0.39-0.83) and lower homocysteine than those with the shortest-telomeres. Amongst subjects with HB12, those with long-telomeres also had a lower mortality than those with short-telomeres (HR:0.40;95%CI:0.27-0.59). IL-6 and hsCRP concentrations were low in HB12LT but were high in HB12ST.

Methods: B12, homocysteine, telomere length (RTL), interleukin-6 (IL-6) and high-sensitive-C-reactive-protein (hsCRP) were measured in 2970 participants of the LURIC study.

Conclusions: Mortality, stratified according to B12 and RTL, seems to be driven by different mechanisms. In LB12 and HB12 subjects, mortality and accelerated telomere shortening might be driven by homocysteine and inflammation, respectively.

Vitamin B12 Intake From Animal Foods, Biomarkers, and Health Aspects

The EAT-Lancet commission recently suggested that transformation to healthy diets by 2050 will require a reduction of at least 50% in consumption of foods such as red meat and sugar, and a doubling in the global consumption of fruits, vegetables, nuts, and legumes. A diet rich in plant-based foods and with fewer animal source foods confers both improved health and environmental benefits. Notably, the risk of vitamin B12 deficiency increases when consuming a diet low in animal products. Humans are dependent on animal foods such as dairy products, meat, fish and eggs. Vitamin B12 deficiency is common worldwide, especially in populations with low consumption of animal foods because of low socioeconomic status, ethical reasons, or because of their lifestyle (i.e., vegans). According to the European Food Safety Authoroty, the recommended adequate intake of vitamin B12 is 4.0 μg/d for adults, and vitamin B12 requirements are higher during pregnancy and lactation. Infants and children from deficient mothers and elderly people are at risk for vitamin B12 deficiency. Diagnosis of vitamin B12 deficiency is hampered by low specificity of available biomarkers, and there is no consensus yet regarding the optimal definition of low vitamin B12 status. In general, a combination of at least two biomarkers is recommended. Therefore, this review presents an overview of vitamin B12 biochemistry and its biomarkers. We further summarize current recommendations of vitamin B12 intake, and evidence on the associations of vitamin B12 intake from different nutrient-dense animal foods with vitamin B12 status markers. Finally, potential consequences of low vitamin B12 status on different health outcomes for pregnant women, infants and elderly are presented.