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6,054 result(s) for "Vitamin B12"
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Rapid Restoration of Circulating Vitamin B12 Levels by Using Oral Sucrosomial® Vitamin B12 in Metformin-Associated B12 Deficiency: Results from a Double-Blind, Placebo-Controlled Randomized Clinical Trial
Background/Objectives: Vitamin B12 deficiency is common in individuals with type 2 diabetes mellitus (T2DM) receiving long-term metformin therapy, primarily due to impaired intestinal absorption. Conventional oral B12 supplementation is often associated with delayed or inconsistent biochemical correction. A lipid-based Sucrosomial® delivery system has been shown to improve circulatory vitamin B12 levels in healthy adults with deficiency, and the present study evaluates its performance in the clinically challenging context of metformin-treated individuals with T2DM, a population characterized by pharmacologically impaired intestinal vitamin B12 absorption. Methods: This multicentre, double-blind, placebo-controlled, parallel-group randomized clinical trial evaluated the efficacy, safety, and tolerability of a Sucrosomial® vitamin B12 formulation in adults with T2DM receiving metformin and presenting with vitamin B12 deficiency. Participants were randomized (1:1) to receive oral Sucrosomial® vitamin B12 (1000 µg daily; n = 25) or placebo (n = 25) for three weeks. Serum total vitamin B12 and holotranscobalamin (HoloTC), the biologically active fraction of vitamin B12, were assessed at baseline and during follow-up, with time-to-normalization and safety analyses performed. Results: Sucrosomial® vitamin B12 supplementation resulted in rapid and sustained increases in circulating vitamin B12 levels, with early separation from placebo, and a substantially higher proportion of participants achieved normalization of serum vitamin B12 concentrations within the three-week period. Parallel improvements in HoloTC levels indicated enhanced biologically active vitamin B12 availability, and the intervention was well tolerated with no clinically relevant safety concerns. Conclusions: These findings demonstrate that an oral Sucrosomial® vitamin B12 formulation can achieve rapid and reliable biochemical repletion of both total and biologically active vitamin B12 in metformin-treated adults with T2DM, despite pharmacologically impaired intestinal absorption, while maintaining a favourable safety and tolerability profile.
A common problem in infants: vitamin B12 deficienc
Background. Nutritional vitamin B12 (VB12 ) deficiency is characterized by anemia, the inability to gain weight, delay or decline in development. Children of mothers with VB12 deficiency have a risk of nutritional VB12 deficiency. Prevention and early treatment are necessary to prevent irreversible neurological damage. We aimed to conduct a retrospective study to understand the characteristics of patients with VB12 deficiency. Methods. Our study included patients admitted to Başkent University Faculty of Medicine Pediatric Hematology outpatient clinic between January 2015 - February 2020 for VB12 deficiency. Their clinical and laboratory characteristics were retrospectively examined through the hospital automation system. Results. Vitamin B12 deficiency was detected in 129 of the 3198 patients; 100 of them were followed regularly. The mean age at admission of our patients was 10 ± 12 months (1 month - 7.5 years); 98% of these children were aged 0-2 years. The mean VB12 level of our patients was 171.63 ± 51.2 pg/ml (83 - 273), mean hemoglobin 11.2 ± 1.37 g/dl (6.3 - 13.9), mean MCV 74.5± 9.1 fl (54-106.5) and mean iron level was 54 ±23 μg/dl (18 - 94). At the end of one month of loading therapy (oral or intramuscular, IM), the average VB12 level was 769 ± 537 pg/ml (post loading). One month after the loading therapy (pre-maintenance) the average VB12 level was 426 ±156 pg/ml. In seven cases who received IM therapy, the loading treatment was performed for the second time. The mean VB12 level of the mothers of 85 cases was 174±127 pg/ml (134 - 650). VB 12 deficiency was detected in 55% of mothers, VB12 level being between 200 - 300 pg/ml in 76%, and below 200 pg/ml in the 24%. The family members of 35% of our patients (including parents) had VB12 deficiency. Conclusions. In our country, routine screening of VB12 levels in infants is not performed; however, its early diagnosis and treatment can prevent many adverse effects mainly on the central nervous system. The fact that 98% of patients were 0-2 years old indicates that its deficiency may be quite high in the young age, and routine screening of this age group for VB12 deficiency and further studies for prophylaxis may be needed.
Vitamin B12 in Cancer Patients: Clinical Insights into Deficiency, Excess, Diagnosis, and Management
Vitamin B12 (cobalamin) is a critical micronutrient involved in hematopoiesis and neurological function. Its deficiency, commonly presenting with anemia and neurological symptoms, is particularly relevant in oncology. While anemia affects up to 60% of cancer patients, the contribution of vitamin B12 deficiency to cancer-related anemia remains underexplored. Additionally, cobalamin-related neuropathy manifests or exacerbates existing chemotherapy-induced peripheral neuropathy (CIPN), a serious side effect of chemotherapy. Prevalence estimates in cancer populations range widely (6–48%), with higher rates in elderly and gastrointestinal cancer patients. This review summarizes current evidence on the prevalence and implications of both vitamin B12 deficiency and excess in patients with solid tumors. It discusses laboratory markers (such as serum vitamin B12, holotranscobalamin, methylmalonic acid, and homocysteine) that could improve diagnostic accuracy in oncology settings. Additionally, it evaluates supplementation strategies and discusses its role in mitigating CIPN. Additionally, it addresses B12′s emerging immunological role in cancer therapy.
Clinical Course of Vitamin B12 Deficiency and Associated Risk Factors in Patients After Total Gastrectomy for Gastric Cancer
Patients are at-risk for vitamin B12 deficiency after total gastrectomy due to a lack of intrinsic factors. The aim of the study was to clarify the clinical course and risk factors for vitamin B12 deficiency after total gastrectomy for gastric cancer patients. Patients who underwent curative resection for gastric cancer were selected from the medical records of the Yokohama City University from 2000 to 2020. A logistic regression analysis was performed to identify risk factors for vitamin B12 deficiency. We evaluated 47 patients. The median serum vitamin B12 levels before surgery were 359 pg/ml, while those at 3, 6, 9, and 12 months after surgery these were 255 pg/ml, 197.5 pg/ml, 195 pg/ml, and 206 pg/ml, respectively. Univariate analyses to identify factors associated with vitamin B12 deficiency at 6 months after surgery showed that the occurrence of postoperative complications was a significant risk factor (OR=6.347, 95%CI=1.607-25.774, p=0.009), while adjuvant chemotherapy was a marginally significantly risk factor (OR=3.562, 95%CI=0.877-14.477, p=0.076). Almost half of the patients were diagnosed with vitamin B12 deficiency at 6 months after total gastrectomy for gastric cancer. In addition, the occurrence of postoperative complications and adjuvant chemotherapy were risk factors for vitamin B12 deficiency at 6 months after surgery.
Imerslund-Gräsbeck syndrome: a comprehensive review of reported cases
Imerslund-Gräsbeck syndrome (IGS) is a rare autosomal recessive disorder characterized by vitamin B12 malabsorption. Most patients present with non-specific symptoms attributed to vitamin B12 deficiency, and proteinuria. Patients may if untreated, develop severe neurocognitive manifestations. If recognized and treated with sufficient doses of vitamin B12, patients recover completely. We provide, for the first time, an overview of all previously reported cases of IGS. In addition, we provide a complete review of IGS and describe two new patients.
Revisiting cost-effectiveness of folic acid supplementation in primary stroke prevention in China: considering vitamin B12 deficiency masking issue
Objectives To identify the cost-effectiveness of four policy options related to folic acid supplements after considering the side effects of masking vitamin B12 (B12) deficiency in primary stroke prevention for hypertensive patients in China. Study Design A cost - effectiveness analysis. Methods Four policies were considered: Policy A, Do nothing to address folate status in hypertensive patients at risk for stroke; Policy B, Folate supplementation without pre-screening for vitamin B12 deficiency; Policy C, Folate supplementation with pre-screening all patients for B12 deficiency and add B12 supplements if B12 is deficient; and Policy D, Folate supplementation only for those whose folate is deficient, pre-screen all patients for both B12 and folate deficiencies and add B12 supplements if B12 is deficient. A decision tree with a five-year period of intervention based on the China Stroke Primary Prevention Trial (CSPPT) from the Chinese healthcare system perspective estimated incremental cost-effectiveness ratio (ICER) for Policy B, Policy C and Policy D vs. Policy A. Results At a willingness to pay (WTP) threshold of 3 times the national GDP per capita ($38,198), Policy B was not cost-effective compared to Policy A, with an ICER of $47,968 per QALY due to QALYs lost introduced by the delayed diagnosis of B12 deficiency and the potentially underestimated costs associated with treating neuropathy. However, Policy C and Policy D were cost-effective compared to Policy A, with an ICER of $32,615 and $20,287 per QALY, respectively. A probabilistic sensitivity analysis showed that there would be a 72.7% and 83.5% chance that the additional cost of Policy C and Policy D, compared with Policy A, was at or below the WTP threshold. Conclusions Folate supplementation with integrated screening for B12 and folate deficiencies is considered the most cost-effective strategy for primary stroke prevention in hypertensive elderly patients in China. Future research should focus on advancing precision medicine to assess the feasibility and cost-effectiveness of nationwide implementation across diverse sub-populations within the context of integrated screening, ensuring efficient and tailored public nutrition strategy delivery.
An update on vitamin B12-related gene polymorphisms and B12 status
Background Vitamin B12 is an essential micronutrient in humans needed for health maintenance. Deficiency of vitamin B12 has been linked to dietary, environmental and genetic factors. Evidence for the genetic basis of vitamin B12 status is poorly understood. However, advancements in genomic techniques have increased the knowledge-base of the genetics of vitamin B12 status. Based on the candidate gene and genome-wide association (GWA) studies, associations between genetic loci in several genes involved in vitamin B12 metabolism have been identified. Objective The objective of this literature review was to identify and discuss reports of associations between single-nucleotide polymorphisms (SNPs) in vitamin B12 pathway genes and their influence on the circulating levels of vitamin B12. Methods Relevant articles were obtained through a literature search on PubMed through to May 2017. An article was included if it examined an association of a SNP with serum or plasma vitamin B12 concentration. Beta coefficients and odds ratios were used to describe the strength of an association, and a P  < 0.05 was considered as statistically significant. Two reviewers independently evaluated the eligibility for the inclusion criteria and extracted the data. Results From 23 studies which fulfilled the selection criteria, 16 studies identified SNPs that showed statistically significant associations with vitamin B12 concentrations. Fifty-nine vitamin B12-related gene polymorphisms associated with vitamin B12 status were identified in total, from the following populations: African American, Brazilian, Canadian, Chinese, Danish, English, European ancestry, Icelandic, Indian, Italian, Latino, Northern Irish, Portuguese and residents of the USA. Conclusion Overall, the data analyzed suggests that ethnic-specific associations are involved in the genetic determination of vitamin B12 concentrations. However, despite recent success in genetic studies, the majority of identified genes that could explain variation in vitamin B12 concentrations were from Caucasian populations. Further research utilizing larger sample sizes of non-Caucasian populations is necessary in order to better understand these ethnic-specific associations.
B-vitamins and body composition: integrating observational and experimental evidence from the B-PROOF study
Purpose Higher folate and vitamin-B12 have been linked to lower risk of overweight. However, whether this is a causal effect of these B-vitamins on obesity risk remains unclear and evidence in older individuals is scarce. This study aimed to assess the role of B-vitamin supplementation and levels on body composition in older individuals. Methods A double-blind, randomized controlled trial in 2919 participants aged ≥ 65 years with elevated homocysteine levels. The intervention comprised a 2-year supplementation with a combination of folic acid (400 µg) and vitamin B12 (500 µg), or with placebo. Serum folate, vitamin-B12, active vitamin-B12 (HoloTC), methylmalonic acid (MMA), and anthropometrics were measured at baseline and after 2 years of follow-up. Dietary intake of folate and vitamin-B12 was measured at baseline in a subsample ( n  = 603) using a validated food-frequency questionnaire. Fat mass index (FMI) and fat-free mass index (FFMI) were assessed with Dual Energy X-ray absorptiometry (DXA). Results Cross-sectional analyses showed that a 1 nmol/L higher serum folate was associated with a 0.021 kg/m 2 lower BMI (95% CI − 0.039; − 0.004). Higher HoloTC (per pmol/L log-transformed) was associated with a 0.955 kg/m 2 higher FMI (95% CI 0.262; 1.647), and higher MMA (per μgmol/L) was associated with a 1.108 kg/m 2 lower FMI (95% CI − 1.899; − 0.316). However, random allocation of B-vitamins did not have a significant effect on changes in BMI, FMI or FFMI during 2 years of intervention. Conclusions Although observational data suggested that folate and vitamin B12 status are associated with body composition, random allocation of a supplement with both B-vitamins combined versus placebo did not confirm an effect on BMI or body composition.
Autoimmune Disease in Turner Syndrome in Sweden: An up to 25 Years’ Controlled Follow-up Study
Abstract Context Turner syndrome (TS) is the most common chromosomal aberration in women; it is the result of structural or numeric abnormalities in the X chromosome. Autoimmune hypothyroidism has been recognized as one of the more prominent disorders associated with TS. Objective This work aimed to study the prevalence of autoimmune diseases in TS. Methods A cross-sectional, longitudinal, 25-year follow-up study was conducted of patients from adult Turner centers at the University Hospitals, Sweden. During 1994 to 2020, a total of 503 women aged 16 to 71 years with TS were evaluated consecutively every fifth year according to national guidelines. A random population sample of women, n = 401, aged 25 to 44 years, from the World Health Organization Monitoring of Trends and Determinants for Cardiovascular Disease (MONICA) project served as controls. Serum thyrotropin, free thyroxine, vitamin B12, antithyroid peroxidase (anti-TPO), and antitransglutaminase antibodies were measured. Results Mean follow-up time (years) was 16 ± 7 for patients and 13 ± 1 for controls. From study start, the prevalence increased in TS for hypothyroidism 40% to 58%, vitamin B12 deficiency 5% to 12%, celiac disease 4% to 7%, positive anti-TPO 26% to 41%, and antitransglutaminase antibodies 6% to 8% (P < .0001 vs controls). Type 1 diabetes and Addison disease were rare. The only interrelationship was between hypothyroidism and vitamin B12 deficiency, both in TS and controls. No association between autoimmune disease and karyotype, antecedent growth hormone treatment, or ongoing estrogen hormone replacement, was seen in TS. Conclusion In women with TS up to older than 80 years, more than half developed hypothyroidism, mainly autoimmune, during follow-up. Awareness of vitamin B12 deficiency and celiac disease throughout life is also recommended in women with TS.
Associations of Genetically Predicted Vitamin Bsub.12 Status across the Phenome
Variation in vitamin B[sub.12] levels has been associated with a range of diseases across the life-course, the causal nature of which remains elusive. We aimed to interrogate genetically predicted vitamin B[sub.12] status in relation to a plethora of clinical outcomes available in the UK Biobank. Genome-wide association study (GWAS) summary data obtained from a Danish and Icelandic cohort of 45,576 individuals were used to identify 8 genetic variants associated with vitamin B[sub.12] levels, serving as genetic instruments for vitamin B[sub.12] status in subsequent analyses. We conducted a Mendelian randomisation (MR)-phenome-wide association study (PheWAS) of vitamin B[sub.12] status with 945 distinct phenotypes in 439,738 individuals from the UK Biobank using these 8 genetic instruments to proxy alterations in vitamin B[sub.12] status. We used external GWAS summary statistics for replication of significant findings. Correction for multiple testing was taken into consideration using a 5% false discovery rate (FDR) threshold. MR analysis identified an association between higher genetically predicted vitamin B[sub.12] status and lower risk of vitamin B deficiency (including all B vitamin deficiencies), serving as a positive control outcome. We further identified associations between higher genetically predicted vitamin B[sub.12] status and a reduced risk of megaloblastic anaemia (OR = 0.35, 95% CI: 0.20–0.50) and pernicious anaemia (0.29, 0.19–0.45), which was supported in replication analyses. Our study highlights that higher genetically predicted vitamin B[sub.12] status is potentially protective of risk of vitamin B[sub.12] deficiency associated with pernicious anaemia diagnosis, and reduces risk of megaloblastic anaemia. The potential use of genetically predicted vitamin B[sub.12] status in disease diagnosis, progression and management remains to be investigated.