Different Supplementation Regimes to Treat Perioperative Vitamin B12 Deficiencies in Bariatric Surgery: a Systematic Review

A Framework to Guide Defining an Upper Threshold of Crystalline Vitamin B12 in Foods and Food Supplements

PURPOSE OF REVIEW

To define an intake threshold of vitamin B12 from food supplements that is sufficient to maintain normal body functions, but it does not cause pharmacological effects.

RECENT FINDINGS

We used studies on the amount of B12 absorbed following oral B12 application and non-comparative case-series studies to synthesize evidence on pharmacological effects of oral B12 (between < 10 µg and 3000 µg) in people with manifested deficiency. There is a dose-dependent intestinal absorption of B12 and in the same time effects on body metabolism and functions. Food supplements providing ≤ 20 µg B12 daily are unlikely to cause pharmacological effects, while 50 µg might correct abnormal biochemical markers in some deficient patients. Foods for special medical purposes for people who cannot absorb B12 may contain 100 µg to 150 µg B12. This dose may ensure 1-4 µg of the vitamin reaching the circulation on a daily basis independent of intrinsic factor. Dosages ≥ 200 µg/d should be considered as drugs that can correct anemia, metabolic markers and clinical symptoms. The content of vitamin B12 in food supplements should not exceed 20 µg. In addition, people with deficiency should receive appropriate medical treatment with high dose B12.

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.

[Postoperative management]

Bariatric surgery results in significant weight loss, reduction or even remission of obesity-associated comorbidities, reduced mortality, and improved quality of life in many patients; however, obesity is a chronic disease, thus follow-up care is required after bariatric surgery. Furthermore, specific issues, such as micronutrient deficiencies and subsequent complications, can arise both in the short-term and the long-term. Abdominal pain after bariatric surgery must always be regarded as a serious symptom. A further focus should be on the diagnosis and treatment of dumping syndrome. Patients with type 2 diabetes should be regularly screened for recurrent hyperglycemia as well as specific sequelae, even though blood glucose levels may be substantially improved or normalized. In addition to centers with multidisciplinary teams, primary care and, in particular, general practitioners will play an increasingly more important role in the follow-up care after bariatric surgery.

Micronutrients in Pregnancy after Bariatric Surgery: A Narrative Review

Bariatric surgery is increasingly used in women of childbearing age due to the rising prevalence of obesity and the effectiveness and availability of this treatment. Pregnancy in women with previous bariatric surgery deserves special attention. Weight loss induced by surgery reduces the risks that obesity poses to pregnancy. But on the other hand, decreased intake and malabsorption may increase the risk of malnutrition and micronutrient deficiency and negatively affect maternal and foetal health. The aim of this narrative review is to provide an updated analysis of the impact of different bariatric surgery techniques on mineral and micronutrient nutritional status during pregnancy and the possible effect on maternal-foetal health.

Expert opinion on the preoperative medical optimization of adults with diabetes undergoing metabolic surgery

Diabetes mellitus (DM) and obesity are interrelated in a complex manner, and their coexistence predisposes patients to a plethora of medical problems. Metabolic surgery has evolved as a promising therapeutic option for both conditions. It is recommended that patients, particularly those of Asian origin, maintain a lower body mass index threshold in the presence of uncontrolled DM. However, several comorbidities often accompany these chronic diseases and need to be addressed for successful surgical outcome. Laparoscopic Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy (LSG) are the most commonly used bariatric procedures worldwide. The bariatric benefits of RYGB and LSG are similar, but emerging evidence indicates that RYGB is more effective than LSG in improving glycemic control and induces higher rates of long-term DM remission. Several scoring systems have been formulated that are utilized to predict the chances of remission. A glycemic target of glycated hemoglobin < 7% is a reasonable goal before surgery. Cardiovascular, pulmonary, gastrointestinal, hepatic, renal, endocrine, nutritional, and psychological optimization of surgical candidates improves perioperative and long-term outcomes. Various guidelines for preoperative care of individuals with obesity have been formulated, but very few specifically focus on the concerns arising from the presence of concomitant DM. It is hoped that this statement will lead to the standardization of presurgical management of individuals with DM undergoing metabolic surgery.

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.

The Effects of Bariatric Surgery on Vitamin B Status and Mental Health

Diet is a modifiable factor that ensures optimal growth, biochemical performance, improved mood and mental functioning. Lack of nutrients, notably vitamin B, has an impact on human health and wellbeing. The United Arab Emirates is facing a serious problem of micronutrient deficiencies because of the growing trend for bariatric surgery, including Roux-en-Y gastric bypass and sleeve gastrectomy. People undergoing bariatric surgery are at high risk of developing neurological, cognitive, and mental disabilities and cardiovascular disease due to deficiency in vitamin B. Vitamin B is involved in neurotransmitter synthesis, including γ-aminobutyric acid, serotonin, dopamine, and noradrenaline. Deficiency of vitamin B increases the risk of depression, anxiety, dementia and Alzheimer's disease. In addition, vitamin B deficiency can disrupt the methylation of homocysteine, leading to hyperhomocysteinemia. Elevated homocysteine levels are detrimental to human health. Vitamin B deficiency also suppresses immune function, increases the production of pro-inflammatory cytokines and upregulates NF-κB. Considering the important functions of vitamin B and the severe consequences associated with its deficiency following bariatric surgery, proper dietary intervention and administration of adequate supplements should be considered to prevent negative clinical outcomes.

Vitamin B12 supplementation orally and intramuscularly in people with obesity undergoing gastric bypass

PURPOSE

Although bariatric surgery can facilitate weight loss and improve many diseases, it impairs the absorption of many vitamins and micronutrients. Vitamin B12 is important for these patients and should be controlled and supplemented postoperatively. The aim of this paper is to compare serum vitamin B12 levels in two forms of supplementation (oral vs. intramuscular) for 6 months after gastric bypass.

METHODS

In a prospective controlled cohort study, people with obesity patients undergoing gastric bypass received vitamin B12 supplementation either orally or intramuscularly. The patients were followed for 6 months, receiving serial doses of vitamin B12 and methylmalonic acid assessment at 6 months.

RESULTS

A total of 53 patients were divided into two homogeneous groups: an oral group (n=24) and an intramuscular group (n=29). Serum vitamin B12 was measured preoperatively and postoperatively at 1, 2, 3, and 6 months. Serum methylmalonic acid was measured at 6 months. At each point, the serum vitamin B12 level remained within reference values in both groups, although it was higher in the oral group (p<0.001). Methylmalonic acid also remained within reference values in both groups, with no significant differences.

CONCLUSION

Despite the anatomical and functional alterations that impair vitamin B12 absorption after gastric bypass, oral vitamin B12 supplementation was as effective as intramuscular in this population.

British Obesity and Metabolic Surgery Society Guidelines on perioperative and postoperative biochemical monitoring and micronutrient replacement for patients undergoing bariatric surgery-2020 update

Bariatric surgery is recognized as the most clinically and cost-effective treatment for people with severe and complex obesity. Many people presenting for surgery have pre-existing low vitamin and mineral concentrations. The incidence of these may increase after bariatric surgery as all procedures potentially cause clinically significant micronutrient deficiencies. Therefore, preparation for surgery and long-term nutritional monitoring and follow-up are essential components of bariatric surgical care. These guidelines update the 2014 British Obesity and Metabolic Surgery Society nutritional guidelines. Since the 2014 guidelines, the working group has been expanded to include healthcare professionals working in specialist and non-specialist care as well as patient representatives. In addition, in these updated guidelines, the current evidence has been systematically reviewed for adults and adolescents undergoing the following procedures: adjustable gastric band, sleeve gastrectomy, Roux-en-Y gastric bypass and biliopancreatic diversion/duodenal switch. Using methods based on Scottish Intercollegiate Guidelines Network methodology, the levels of evidence and recommendations have been graded. These guidelines are comprehensive, encompassing preoperative and postoperative biochemical monitoring, vitamin and mineral supplementation and correction of nutrition deficiencies before, and following bariatric surgery, and make recommendations for safe clinical practice in the U.K. setting.

Effects of Microecological Preparations on Obese Patients after Bariatric Surgery: A Systematic Review and Meta-Analysis

Vitamin deficiency, bacterial overgrowth, and gastrointestinal symptoms can be detected in obese patients after bariatric surgery that influences their quality of life (QoL) and weight. It is unclear if microecological preparations benefit obese patients following bariatric surgery. The aim of this study is to investigate the effects of microecological preparations on QoL, excess weight loss (EWL), and levels of vitamin B₁₂ and inflammatory markers. We searched seven databases to identify reports published till December 1, 2019, and included randomized controlled trials investigating the effects of microecological preparations in obese adults undergoing bariatric surgery. The primary outcomes included QoL and EWL, while secondary outcomes comprised serum levels of vitamin B₁₂, interleukin 6, TNF-α, and C-reactive protein (CRP). Study bias was analyzed using the Cochrane risk-of-bias tool. Statistical analyses were performed using Review Manager. The mean difference in outcomes was calculated using standardized mean difference (SMD) with a confidence interval (CI) of 95%. A majority of the studies showed a low or moderate risk of bias. Meta-analysis showed significantly higher levels of vitamin B₁₂ in postoperative patients administered with microecological preparations (SMD = 0.52; 95% CI = 0.08–0.95; P = 0.02). There were no significant differences in QoL (SMD = −0.14; 95% CI = −0.45–0.17; P = 0.38), EWL (SMD = 0.45; 95% CI = −0.16–1.05; P = 0.15), and levels of TNF-α (SMD = −0.29; 95% CI = −0.64–0.05; P = 0.09), interleukin 6 (SMD = −0.1; 95% CI = −0.81–0.61; P = 0.78]), and CRP (SMD = 0.02; 95% CI = −0.32–0.36; P = 0.93). The trials examined indicated that microecological preparations had limited efficacy in improving QoL, EWL, and inflammatory response, but they stimulated the synthesis of vitamin B₁₂. This may help in designing efficient microecological preparations to supplement bariatric surgery in obese individuals.

Clinical Practice Guidelines for the Perioperative Nutrition, Metabolic, and Nonsurgical Support of Patients Undergoing Bariatric Procedures - 2019 Update: Cosponsored by American Association of Clinical Endocrinologists/American College of Endocrinology, The Obesity Society, American Society for Metabolic and Bariatric Surgery, Obesity Medicine Association, and American Society of Anesthesiologists

OBJECTIVE

The development of these updated clinical practice guidelines (CPGs) was commissioned by the American Association of Clinical Endocrinologists (AACE), The Obesity Society (TOS), American Society for Metabolic and Bariatric Surgery (ASMBS), Obesity Medicine Association (OMA), and American Society of Anesthesiologists (ASA) Boards of Directors in adherence with the AACE 2017 protocol for standardized production of CPGs, algorithms, and checklists.

METHODS

Each recommendation was evaluated and updated based on new evidence from 2013 to the present and subjective factors provided by experts.

RESULTS

New or updated topics in this CPG include: contextualization in an adiposity-based chronic disease complications-centric model, nuance-based and algorithm/checklist-assisted clinical decision-making about procedure selection, novel bariatric procedures, enhanced recovery after bariatric surgery protocols, and logistical concerns (including cost factors) in the current health care arena. There are 85 numbered recommendations that have updated supporting evidence, of which 61 are revised and 12 are new. Noting that there can be multiple recommendation statements within a single numbered recommendation, there are 31 (13%) Grade A, 42 (17%) Grade B, 72 (29%) Grade C, and 101 (41%) Grade D recommendations. There are 858 citations, of which 81 (9.4%) are evidence level (EL) 1 (highest), 562 (65.5%) are EL 2, 72 (8.4%) are EL 3, and 143 (16.7%) are EL 4 (lowest).

CONCLUSIONS

Bariatric procedures remain a safe and effective intervention for higher-risk patients with obesity. Clinical decision-making should be evidence based within the context of a chronic disease. A team approach to perioperative care is mandatory, with special attention to nutritional and metabolic issues.

A Spanish Society joint SECO and SEEDO approach to the Post-operative management of the patients undergoing surgery for obesity

PURPOSE

Bariatric surgery is the method of choice for the management or treatment of obesity. Bariatric surgery brings about several physiological changes in the body and is associated with set of complications. The aim of this study is to provide guidelines on post bariatric surgery management based on consensus by the Spanish society for Obesity Surgery (Sociedad Española de Cirugía de la Obesidad) (SECO) and the Spanish Society for the Study of Obesity (Sociedad Española para el Estudio de la Obesidad) (SEEDO).

METHOD

The boards proposed seven experts from each society. The experts provided the evidence and a grade of recommendation on the selected topics based on systematic reviews/meta-analysis. A list of clinical practical recommendations levels of evidence and grades of these recommendations was derived from the consensus statements from the members of these societies.

RESULTS

Seventeen topics related to post-operative management were reviewed after bariatric surgery. The experts came with 47 recommendations and statements. The mean number of persons voting at each statement was 54 (range 36-76).

CONCLUSION

In this consensus, we have designed a set of guidelines to be followed while managing patients after bariatric surgery. Expertise and knowledge of the clinicians are required to convey suitable considerations to the post-bariatric patients. There should also be extensive follow-up plans for the bariatric surgery patients.

Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures - 2019 update: cosponsored by American Association of Clinical Endocrinologists/American College of Endocrinology, The Obesity Society, American Society for Metabolic & Bariatric Surgery, Obesity Medicine Association, and American Society of Anesthesiologists

OBJECTIVE

The development of these updated clinical practice guidelines (CPG) was commissioned by the American Association of Clinical Endocrinologists, The Obesity Society, the American Society of Metabolic and Bariatric Surgery, the Obesity Medicine Association, and the American Society of Anesthesiologists boards of directors in adherence to the American Association of Clinical Endocrinologists 2017 protocol for standardized production of CPG, algorithms, and checklists.

METHODS

Each recommendation was evaluated and updated based on new evidence from 2013 to the present and subjective factors provided by experts.

RESULTS

New or updated topics in this CPG include contextualization in an adiposity-based, chronic disease complications-centric model, nuance-based, and algorithm/checklist-assisted clinical decision-making about procedure selection, novel bariatric procedures, enhanced recovery after bariatric surgery protocols, and logistical concerns (including cost factors) in the current healthcare arena. There are 85 numbered recommendations that have updated supporting evidence, of which 61 are revised and 12 are new. Noting that there can be multiple recommendation statements within a single numbered recommendation, there are 31 (13%) Grade A, 42 (17%) Grade B, 72 (29%) Grade C, and 101 (41%) Grade D recommendations. There are 858 citations, of which 81 (9.4%) are evidence level (EL) 1 (highest), 562 (65.5%) are EL 2, 72 (8.4%) are EL 3, and 143 (16.7%) are EL 4 (lowest).

CONCLUSIONS

Bariatric procedures remain a safe and effective intervention for higher-risk patients with obesity. Clinical decision-making should be evidence-based within the context of a chronic disease. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Neuropathy by folic acid supplementation in a patient with anaemia and an untreated cobalamin deficiency: a case report

The rising rates of bariatric surgery (BS) are accompanied by neurological complications related to nutrient deficiencies. One of the risk factors for neurological complications in BS patients is poor vitamin and mineral supplementation. Prevention, diagnosis and treatment of these disorders are necessary parts of lifelong care after BS. Particularly important for optimal functioning of the nervous system are vitamin B₁ , B₆ , B₁₂ (cobalamin), E, copper and possibly vitamin B₁₁ (folic acid). In this case report, we narrate about a patient with anaemia and multiple vitamin and mineral deficiencies after Roux-en-Y gastric bypass (RYGB) with an alimentary limb of 150 cm and a biliopancreatic limb of 100 cm. RYGB is associated with an increased risk of vitamin deficiencies, especially a vitamin B₁₂ deficiency. The patient in this case report developed psychiatric-neurological symptoms due to folic acid supplementation in an untreated cobalamin deficiency. Second, we tried to elucidate the vitamin physiology to understand specific mechanisms after BS.

Problems in bariatric patient care - challenges for dieticians

Obesity management options include a low-calorie diet, behavioral therapy, regular physical activity and pharmacological therapy. However, treatment failure is frequently encountered, most of these methods are ineffective, and a positive outcome is rarely maintained in the long term. In morbidly obese patients, bariatric surgery is considered the most effective treatment for obesity as well as the accompanying diseases. Bariatric surgery promotes much greater weight loss than conservative treatment, regardless of the applied surgical technique. Bariatric surgery patients should receive professional perioperative (preoperative, intraoperative and postoperative) care from a multidisciplinary team of specialists, including a bariatric surgeon, a general practitioner, a dietitian and a health psychologist. Patients require postoperative nutritional counseling to be able to stabilize their weight and maintain long-term weight loss after surgery. Patients are guided by bariatric dietitians through the process of adopting new eating habits and behavior, learning how to make healthy food choices.