Oral versus intramuscular administration of vitamin B12 for vitamin B12 deficiency in primary care: a pragmatic, randomised, non-inferiority clinical trial (OB12)

Oral vitamin B12 supplementation in pernicious anemia: a prospective cohort study

BACKGROUND

The absorption of vitamin B12 is hindered in pernicious anemia (PA) owing to intrinsic factor deficiency. Traditionally, intramuscular vitamin B12 injections were the standard treatment, bypassing the impaired absorption. Although there is potential for oral vitamin B12 supplementation through passive enteral absorption, it is not commonly prescribed in PA owing to limited studies assessing its efficacy.

OBJECTIVES

We aimed to assess the efficacy of oral vitamin B12 supplementation in PA.

METHODS

We enrolled participants diagnosed with incident vitamin B12 deficiency related to PA. The diagnosis of PA was based on the presence of classical immune gastritis and of anti-intrinsic factor and/or antiparietal cell antibodies. To evaluate the vitamin B12 status, we measured total plasma vitamin B12, plasma homocysteine, and plasma methylmalonic acid (pMMA) concentration and urinary methylmalonic acid-to-creatinine ratio. Participants were treated with oral cyanocobalamin at a dosage of 1000 μg/d throughout the study duration. Clinical and biological vitamin B12 deficiency related features were prospectively and systematically assessed over the 1-y study duration.

RESULTS

We included 26 patients with vitamin B12 deficiency revealing PA. Following 1 mo of oral vitamin B12 supplementation, 88.5% of patients were no longer deficient in vitamin B12, with significant improvement of plasma vitamin B12 [407 (297-485) compared with 148 (116-213) pmol/L; P < 0.0001], plasma homocysteine [13.5 (10.9-29.8) compared with 18.6 (13.7-46.8) μmol/L; P < 0.0001], and pMMA [0.24 (0.16-0.38) compared with 0.56 (0.28-1.09) pmol/L; P < 0.0001] concentrations than those at baseline. The enhancement of these biological parameters persisted throughout the 12-month follow-up, with no patients showing vitamin B12 deficiency by the end of the follow-up period. The median time to reverse initial vitamin B12 deficiency abnormalities ranged from 1 mo for hemolysis to 4 mo for mucosal symptoms.

CONCLUSIONS

Oral supplementation with 1000 μg/d of cyanocobalamin has been shown to improve vitamin B12 deficiency in PA.

Development of a Vitamin B12 Deficiency Patient-Reported Outcome Measure for Clinical Practice and Research

BACKGROUND

It is difficult to recognize vitamin B12 deficiency and to evaluate the effect of B12 treatment due to a broad range of variable clinical symptoms overlapping with other diseases and diagnostic biomarkers that quickly normalize during treatment. This poses a risk of delay in diagnosis and a challenge to uniformly monitor the effect of B12 treatment. There is a need for a new clinical outcome measure suitable for clinical practice and clinical evaluation studies.

OBJECTIVE

To develop a Patient-Reported Outcome Measure (PROM) which measures the severity of vitamin B12 deficiency symptoms.

METHODS

The B12 PROM was developed by (1) gathering input from experts and literature review to define a construct and develop a conceptual model, (2) processing input from health care providers, scientists, and patients to develop items and response options, and (3) improving items based on the feedback from laypersons, test interviews, semi-structured cognitive interviews with patients, and forward and backward translation (ENG-NL).

RESULTS

The B12 PROM includes 62 items grouped into 8 categories of symptoms related to vitamin B12 deficiency (General, Senses, Thinking, In limbs and/or face, Movement, Emotions, Mouth & Abdomen, Urinary tract & Reproductive organs). Cognitive interviews demonstrated good comprehensibility and comprehensiveness.

CONCLUSIONS

This study is the first step in the development of a disease-specific PROM for vitamin B12 deficiency to measure the burden of symptoms. Further validation and reliability testing are necessary before the PROM can be applied in clinical practice and research.

Efficacy of different routes of vitamin B12 supplementation for the treatment of patients with vitamin B12 deficiency: A systematic review and network meta-analysis

BACKGROUND

This systematic review and network meta-analysis aimed to evaluate the three different administration routes of vitamin B12: oral, intramuscular (IM), and sublingual (SL) routes.

METHODS

We searched four electronic databases (PubMed, Scopus, Web of Science, and Cochrane CENTRAL Register of Controlled Trials). We included only comparative studies. We performed a frequentist network meta-analysis to measure network estimates for the relative outcomes. Moreover, we conducted a pairwise meta-analysis using a random effect model to obtain direct estimates for outcomes. All outcomes were continuous, and the relative treatment effects were pooled as mean difference (MD) with 95% confidence intervals.

RESULTS

Thirteen studies were included in the meta-analysis, with a total of 4275 patients. Regarding increasing vitamin B12 levels, the IM route ranked first, followed by the SL route (MD = 94.09 and 43.31 pg/mL, respectively) compared to the oral route. However, these differences did not reach statistical significance owing to the limited number of studies. Regarding the hemoglobin level, the pooled effect sizes showed no difference between all routes of administration that could reach statistical significance. However, the top two ranked administration routes were the oral route (78.3) and the IM route (49.6).

CONCLUSION

All IM, oral, and SL routes of administration of vitamin B12 can effectively increase the level of vitamin B12 without significant differences between them, as thought previously. However, the IM route was the top-ranked statistically but without clinical significance. We found no significant difference among studied administrated routes in all other CBC parameters and homocysteine levels.

A Rare Cause of Vitamin B12 Deficiency in the Pediatric Age

Vitamin B12 plays an important role in DNA synthesis, hematopoiesis, and neuronal mechanisms, and its deficiency can be associated with insufficient intake or poor absorption and autoimmune and genetic diseases. Although rare, excessive, and chronic alcohol consumption may also justify a deficiency in this vitamin. We present a case of a 17-year-old Iraqi adolescent refugee in Portugal with a deficiency of vitamin B12 due to excessive and chronic alcohol consumption. Although intramuscular (IM) supplementation with cyanocobalamin is the most used, it was decided to initiate oral supplementation. After four months, vitamin B12 levels were replenished. With this clinical case, we aim to raise awareness of the cause of cyanocobalamin deficiency, which although rare in pediatric age should be considered in adolescents, given the possibility of risky behaviors in this age group. Additionally, given the therapeutic options, we have found that oral administration of vitamin B12 has been effective, as reported in the literature.

Diagnosis, Treatment and Long-Term Management of Vitamin B12 Deficiency in Adults: A Delphi Expert Consensus

Background/Objectives: Vitamin B12 deficiency can cause variable symptoms, which may be irreversible if not diagnosed and treated in a timely manner. We aimed to develop a widely accepted expert consensus to guide the practice of diagnosing and treating B12 deficiency. Methods: We conducted a scoping review of the literature published in PubMed since January 2003. Data were used to design a two-round Delphi survey to study the level of consensus among 42 experts. Results: The panelists agreed on the need for educational and organizational changes in the current medical practices for diagnosing and treating B12 deficiency. Recognition of clinical symptoms should receive the highest priority in establishing the diagnosis. There is agreement that the serum B12 concentration is useful as a screening marker and methylmalonic acid or homocysteine can support the diagnosis. Patient lifestyle, disease history, and medications can provide clues to the cause of B12 deficiency. Regardless of the cause of the deficiency, initial treatment with parenteral B12 was regarded as the first choice for patients with acute and severe manifestations of B12 deficiency. The use of high-dose oral B12 at different frequencies may be considered for long-term treatment. Prophylactic B12 supplementation should be considered for specific high-risk groups. Conclusions: There is a consensus that clinical symptoms need to receive more attention in establishing the diagnosis of B12 deficiency. B12 laboratory markers can support the diagnosis. The severity of clinical symptoms, the causes of B12 deficiency, and the treatment goals govern decisions regarding the route and dose of B12 therapy.

[Neurological complications resulting of nitrous oxide intoxication]

Nitrous oxide (NO) intoxication is a common consequence of its inhalation with recreational purpose, which is prevalent among young people. The most severe result of such an entertainment is development of myelopolyneuropathy with polyneuropathy as the most common presentation, which may start acutely or subacutely. The underlying cause of neurological complications of NO intoxication is deficit of B12 vitamin, however its laboratory confirmation may be challenging. The key aspect of treatment of neurological symptoms in such patients is prescription of adequate dosage of B12 for a long period of time. In this paper we present the clinical case, which demonstrates challenges of vitamin B12 deficiency verification and advantages of oral cyanocobalamin prescription.

Points to Consider in Health Assessment of Adult Patients with Primary Antibody Deficiencies

An improved recognition of inborn errors of immunity (IEI) is associated with an increase in life expectancy and a higher incidence of complications and related conditions. The aim of the study was to analyze factors enabling the primary prevention: BMI, smoking and selected laboratory tests (morphology with smear, creatinine, eGFR, total protein, albumin, ferritin, folic acid, vitamin B12, vitamin D3) included in the protocols of standard of care for adult patients with primary antibody deficiencies (PADs). The study included 94 participants ≥ 18 years old, diagnosed with PADs. Overweight was found in 17%, obesity in 14% and underweight in 15% of patients; 11.5% of patients smoked. Leukopenia was diagnosed in 16%, neutropenia in 8.5%, lymphopenia in 22.5% and thrombocytopenia in 14% of patients. A decreased concentration of hemoglobin was found in 32%, total protein in 19%, albumin in 17%, vitamin D3 in 52%, vitamin B12 in 6.5%, folic acid in 34% and ferritin in 26% of patients. Creatinine concentrations were elevated in 16% of patients, while in 20%, eGFR was reduced. Only a holistic assessment of comorbidities and complications of deficiency, as well as regular follow-up and lifestyle changes, can yield the best results in the long-term care of patients.

Vitamin B12 in Foods, Food Supplements, and Medicines-A Review of Its Role and Properties with a Focus on Its Stability

Vitamin B₁₂, also known as the anti-pernicious anemia factor, is an essential micronutrient totally dependent on dietary sources that is commonly integrated with food supplements. Four vitamin B₁₂ forms-cyanocobalamin, hydroxocobalamin, 5'-deoxyadenosylcobalamin, and methylcobalamin-are currently used for supplementation and, here, we provide an overview of their biochemical role, bioavailability, and efficacy in different dosage forms. Since the effective quantity of vitamin B₁₂ depends on the stability of the different forms, we further provide a review of their main reactivity and stability under exposure to various environmental factors (e.g., temperature, pH, light) and the presence of some typical interacting compounds (oxidants, reductants, and other water-soluble vitamins). Further, we explore how the manufacturing process and storage affect B₁₂ stability in foods, food supplements, and medicines and provide a summary of the data published to date on the content-related quality of vitamin B₁₂ products on the market. We also provide an overview of the approaches toward their stabilization, including minimization of the destabilizing factors, addition of proper stabilizers, or application of some (innovative) technological processes that could be implemented and contribute to the production of high-quality vitamin B₁₂ products.

Inherited and acquired vitamin B12 deficiencies: Which administration route to choose for supplementation?

Vitamin B12 or cobalamin deficiency is a commonly encountered clinical scenario and most clinicians will have familiarity prescribing Vitamin B12 to treat their patients. Despite the high prevalence of this condition, there is widespread heterogeneity regarding routes, schedules and dosages of vitamin B12 administration. In this review, we summarise the complex metabolic pathway of Vitamin B12, the inherited and acquired causes of Vitamin B12 deficiency and subsequently highlight the disparate international practice of prescribing Vitamin B12 replacement therapy. We describe the evidence base underpinning the novel sublingual, intranasal and subcutaneous modes of B12 replacement in comparison to intramuscular and oral routes, with their respective benefits for patient compliance and cost-saving.

Vegan nutrition: a preliminary guide for health professionals

Since the beginning of the 21st century, interest in vegan diets has been rapidly increasing in most countries. Misconceptions about vegan diets are widespread among the general population and health professionals. Vegan diets can be health-promoting and may offer certain important advantages compared to typical Western (and other mainstream) eating patterns. However, adequate dietary sources/supplements of nutrients of focus specific to vegan diets should be identified and communicated. Without supplements/fortified foods, severe vitamin B12 deficiency may occur. Other potential nutrients of focus are calcium, vitamin D, iodine, omega-3 fatty acids, iron, zinc, selenium, vitamin A, and protein. Ensuring adequate nutrient status is particularly important during pregnancy, lactation, infancy, and childhood. Health professionals are often expected to be able to provide advice on the topic of vegan nutrition, but a precise and practical vegan nutrition guide for health professionals is lacking. Consequently, it is important and urgent to provide such a set of dietary recommendations. It is the aim of this article to provide vegan nutrition guidelines, based on current evidence, which can easily be communicated to vegan patients/clients, with the goal of ensuring adequate nutrient status in vegans.

Stability Indicating RP-HPLC method for Methylcobalamin determination in different dosage forms: application to photodegradation kinetics and pH-rate profiling

A stability-indicating RP-HPLC method for methylcobalamin determination was developed. Stress degradation under variable conditions was carried out. Methylcobalamin had pronounced susceptibility to hydrolysis under acidic, alkaline, and photolytic conditions; further study of photolytic degradation kinetics and pH rate profiling over pH range 2-11 was carried out. Photodegradation of methylcobalamin followed zero-order kinetics with half-life 0.99hour equivalent to 1971.53 lux. Methylcobalamin followed pseudo first order kinetics upon exposure to acidic and alkaline hydrolysis with highest stability at pH 5 and least stability at pH 2. Optimization of chromatographic conditions was performed using two level full factorial design, chromatographic analysis was executed using Inertsil^® column (250×4.6 mm, 5μm) maintained at 25^◦ C. Elution was carried out using 25mM potassium dihydrogen phosphate (pH adjusted with phosphoric acid to 3.8): methanol: acetonitrile (55:35:10, v/v) as mobile phase. The flow rate was 1.0 mL/min. Detection was carried out at 220 nm using diode array detector. The method was validated as per ICH guidelines; the linearity was over concentration range 2-160 μg/mL with coefficient of determination 0.9995. The method was effectively applied for determination of methylcobalamin in Cobalvex^® ampoule, cobal^® tablet, cobal-F^® tablet and methyltechon^® oral dissolvable film without interfering from excipients within run time six minutes. This article is protected by copyright. All rights reserved.

Clinical relevance of testing for metabolic vitamin B12 deficiency in patients with polyneuropathy

OBJECTIVE

Determine vitamin B12 threshold levels below which additional testing of methylmalonic acid (MMA) and/or homocysteine (Hcy) is useful to diagnose metabolic vitamin B12 deficiency in patients with polyneuropathy, and how vitamin B12, MMA and Hcy levels relate to the effect of supplementation therapy.

METHODS

In a retrospective cohort study of 331 patients with polyneuropathy, vitamin B12, MMA and Hcy were measured. Linear regression models with vitamin B12 as dependent and Hcy or MMA as covariate were compared, to assess which was best related to vitamin B12. Threshold vitamin B12 levels for metabolic deficiency (defined as elevatede metabolites) were determined using logistic regression with elevated metabolites as dependent and vitamin B12 as covariate.. A structured interview was conducted in 42 patients to evaluate response to vitamin B12 supplementation.

RESULTS

MMA was best related to vitamin B12. Using elevated MMA for metabolic deficiency, we found 90% sensitivity at a vitamin B12 threshold level <264 pmol/L (358 pg/mL) and 95% sensitivity at <304 pmol/L (412 pg/mL). Improvement after supplementation was reported by 19% patients and stabilization by 24%. 88% of patients with improvement and 90% with stabilization either had absolute deficiency (Vitamin B12 < 148 pmol/L) or metabolic deficiency (elevated MMA and vitamin B12 ≥ 148 pmol/L). There were no additional patients with improvement or stabilization with isolated elevated Hcy.

CONCLUSION

Testing of MMA has additional value in identifying patients with clinically relevant metabolic deficiency when vitamin B12 is below 304 pmol/L (412 pg/mL). Supplementation can be effective in patients with absolute and metabolic deficiency.

Testing and Prescribing Vitamin B12 in Swiss General Practice: A Survey among Physicians

Testing and prescribing vitamin B12 (also known as cobalamin) is increasing in Switzerland but substantial variation among general practitioners (GPs) with respect to testing has been noted. In this study, we aimed at exploring GPs’ mindsets regarding vitamin B12 testing and prescribing. A cross-sectional study was conducted using an online survey distributed by e-mail to Swiss GPs. The questionnaire explored mindsets related to testing and prescribing vitamin B12 in specific clinical situations, as well as testing and prescribing strategies. The questionnaire was sent to 876 GPs and 390 GPs responded (44.5%). The most controversial domains for testing and prescribing vitamin B12 were idiopathic fatigue (57.4% and 43.4% of GPs agreed, respectively) and depressive symptoms (53.0% and 35.4% of GPs agreed, respectively). There was substantial variation among GPs with regard to testing strategies (89.5% of GPS used a serum cobalamin test, 71.3% of GPS used holotranscobalamin, and 27.6% of GPs used homocysteine or methylmalonic acid). Intramuscular injection was the predominantly prescribed route of application (median of 87.5% of the prescriptions). In this study, we focus on discordant mindsets that can be specifically targeted by using educational interventions, and research questions that still need answering specifically about the effectiveness of vitamin B12 for idiopathic fatigue.

Vitamin B12 status in health and disease: a critical review. Diagnosis of deficiency and insufficiency - clinical and laboratory pitfalls

Vitamin B₁₂ (cobalamin) is an essential cofactor for two metabolic pathways. It is obtained principally from food of animal origin. Cobalamin becomes bioavailable through a series of steps pertaining to its release from dietary protein, intrinsic factor-mediated absorption, haptocorrin or transcobalamin-mediated transport, cellular uptake, and two enzymatic conversions (via methionine synthase and methylmalonyl-CoA-mutase) into cofactor forms: methylcobalamin and adenosylcobalamin. Vitamin B₁₂ deficiency can masquerade as a multitude of illnesses, presenting different perspectives from the point of view of the hematologist, neurologist, gastroenterologist, general physician, or dietician. Increased physician vigilance and heightened patient awareness often account for its early presentation, and testing sometimes occurs during a phase of vitamin B₁₂ insufficiency before the main onset of the disease. The chosen test often depends on its availability rather than on the diagnostic performance and sensitivity to irrelevant factors interfering with vitamin B₁₂ markers. Although serum B₁₂ is still the most commonly used and widely available test, diagnostics by holotranscobalamin, serum methylmalonic acid, and plasma homocysteine measurements have grown in the last several years in routine practice. The lack of a robust absorption test, coupled with compromised sensitivity and specificity of other tests (intrinsic factor and gastric parietal cell antibodies), hinders determination of the cause for depleted B₁₂ status. This can lead to incorrect supplementation regimes and uncertainty regarding later treatment. This review discusses currently available knowledge on vitamin B₁₂, informs the reader about the pitfalls of tests for assessing its deficiency, reviews B₁₂ status in various populations at different disease stages, and provides recommendations for interpretation, treatment, and associated risks. Future directions for diagnostics of B₁₂ status and health interventions are also discussed.

Current Nanocarrier Strategies Improve Vitamin B12 Pharmacokinetics, Ameliorate Patients' Lives, and Reduce Costs

Vitamin B12 (VitB12) is a naturally occurring compound produced by microorganisms and an essential nutrient for humans. Several papers highlight the role of VitB12 deficiency in bone and heart health, depression, memory performance, fertility, embryo development, and cancer, while VitB12 treatment is crucial for survival in inborn errors of VitB12 metabolism. VitB12 is administrated through intramuscular injection, thus impacting the patients’ lifestyle, although it is known that oral administration may meet the specific requirement even in the case of malabsorption. Furthermore, the high-dose injection of VitB12 does not ensure a constant dosage, while the oral route allows only 1.2% of the vitamin to be absorbed in human beings. Nanocarriers are promising nanotechnology that can enable therapies to be improved, reducing side effects. Today, nanocarrier strategies applied at VitB12 delivery are at the initial phase and aim to simplify administration, reduce costs, improve pharmacokinetics, and ameliorate the quality of patients’ lives. The safety of nanotechnologies is still under investigation and few treatments involving nanocarriers have been approved, so far. Here, we highlight the role of VitB12 in human metabolism and diseases, and the issues linked to its molecule properties, and discuss how nanocarriers can improve the therapy and supplementation of the vitamin and reduce possible side effects and limits.

Is There a Carcinogenic Risk Attached to Vitamin B12 Deficient Diets and What Should We Do About It? Reviewing the Facts

The number of individuals partaking in veganism has increased sharply in the last decade. Therefore, it is critical to look at the implications of vegan diets for public health. Although there are multiple health benefits of a vegan diet, studies have also linked the diet with deficiencies in various micronutrients. This study focuses on vitamin B12, because of its critical role in DNA synthesis and methylation. In light of these connections, a critical review of recent scientific literature is conducted to understand the effects of a B12 deficient diet on the genome and epigenome, and whether it can give rise to cancer. It is observed that a B12 deficiency leads to increased uracil misincorporation, leading to impaired DNA synthesis and genomic instability. The deficiency also leads to global hypomethylation of DNA, a hallmark of early carcinogenesis. The findings of this study highlight the need for increased awareness among vegans to ensure adequate B12 intake through supplementation or consumption of fortified products as a preventative measure. Additionally, the biofortification of staple crops and an improved version of fermented products with increased B12 content can be developed when inadequate intake seems otherwise inevitable.