Origins of and Recognition of Micronutrient Deficiencies After Gastric Bypass Surgery

Roux-en-Y gastric bypass surgery remains the major surgical option for individuals with medically complicated obesity. The importance of preoperative evaluation to permit identification of micronutrient deficiencies is being re-evaluated. The risk of complications related to pregnancy after gastric bypass supports careful follow-up. Micronutrient deficiencies are common in postoperative gastric bypass patients, despite the suggested use of routine vitamin and mineral supplements after surgery. Copper deficiency must be considered as an origin for visual disorders after gastric bypass. Vitamin D deficiency with metabolic bone disease remains common after gastric bypass and the results suggest that the present postoperative supplements of calcium and vitamin D are inadequate. Major nutritional complications of bariatric surgery are occurring more than 20 years after surgery. There is no evidence for intestinal adaptation as there remains decreased intestinal absorption of iron up to 18 months after gastric bypass surgery. This article supports ongoing examination of nutritional complications after gastric bypass surgery and supports the notion that the daily doses of micronutrient supplements, such as vitamin D, may need to be revised.     

Nutritional deficiencies after bariatric surgery

Lifestyle intervention programmes often produce insufficient weight loss and poor weight loss maintenance. As a result, an increasing number of patients with obesity and related comorbidities undergo bariatric surgery, which includes approaches such as the adjustable gastric band or the 'divided' Roux-en-Y gastric bypass (RYGB). This Review summarizes the current knowledge on nutrient deficiencies that can develop after bariatric surgery and highlights follow-up and treatment options for bariatric surgery patients who develop a micronutrient deficiency. The major macronutrient deficiency after bariatric surgery is protein malnutrition. Deficiencies in micronutrients, which include trace elements, essential minerals, and water-soluble and fat-soluble vitamins, are common before bariatric surgery and often persist postoperatively, despite universal recommendations on multivitamin and mineral supplements. Other disorders, including small intestinal bacterial overgrowth, can promote micronutrient deficiencies, especially in patients with diabetes mellitus. Recognition of the clinical presentations of micronutrient deficiencies is important, both to enable early intervention and to minimize long-term adverse effects. A major clinical concern is the relationship between vitamin D deficiency and the development of metabolic bone diseases, such as osteoporosis or osteomalacia; metabolic bone diseases may explain the increased risk of hip fracture in patients after RYGB. Further studies are required to determine the optimal levels of nutrient supplementation and whether postoperative laboratory monitoring effectively detects nutrient deficiencies. In the absence of such data, clinicians should inquire about and treat symptoms that suggest nutrient deficiencies.     

Nutritional deficiencies associated with bariatric surgery

Morbidly obese patients often have nutritional deficiencies, particularly in fat-soluble vitamins, folic acid and zinc. After bariatric surgery, these deficiencies may increase and others can appear, especially because of the limitation of food intake in gastric reduction surgery and of malabsorption in by-pass procedures. The latter result in more important weight loss but also increase the risk of more severe deficiencies. The protein deficiency associated with a decrease in the fat-free mass has been described in both procedures. It can sometimes require an enteral or parenteral support. Anemia can be secondary to iron deficiency, folic acid deficiency and even to vitamin B12 deficiency. Neurological disorders such as Gayet-Wernicke encephalopathy due to thiamine deficiency, or peripheral neuropathies may also be observed. Malabsorption of fat-soluble vitamins and other nutrients, especially if diagnosed after by-pass surgery, rarely cause clinical symptoms. However, some complications have been reported such as bone demineralization due to vitamin D deficiency, hair loss secondary to zinc deficiency or hemeralopia from vitamin A deficiency. A careful nutritional follow-up should be performed during pregnancy after obesity surgery, because possible deficiencies can affect the health of both the mother and child. In conclusion, increased awareness of the risk of deficiency and the systematic dosage of micronutrients are needed in the pre- and postoperative period in obese patients undergoing bariatric surgery. The case by case correction of these deficiencies is mandatory, and their systematic prevention should be evaluated.     

Bariatric surgery: a review of procedures and outcomes

The prevalence of obesity has increased in recent decades, and obesity is now one of the leading public health concerns on a worldwide scale. There is accumulating agreement that bariatric surgery is currently the most efficacious and enduring treatment for clinically severe obesity, and as a result, the number of bariatric surgery procedures performed has risen dramatically in recent years. This review will summarize historic and contemporary bariatric surgical techniques, including gastric bypass (open and laparoscopic), laparoscopic adjustable gastric banding, and biliopancreatic diversion (with or without duodenal switch). Data are presented on bariatric surgery outcomes, focusing on weight loss and obesity-related comorbidities. We also review possible complications from surgery. Bariatric surgery patients undergo many dramatic lifestyle changes, and comprehensive presurgical screening conducted by a multidisciplinary team is important to prepare patients for the numerous changes necessary for successful outcome. In addition, comprehensive presurgical screening can aid the treatment team in identifying patients who would benefit from additional services prior to or following surgery. Further research focused on presurgical variables that predict outcome-especially the longer term outcome-of bariatric surgery is needed. At present, approximately 1% of eligible individuals with morbid obesity receive bariatric surgery. In addition, there appears to be inequity in access to weight loss surgery. Given the accumulating evidence that bariatric surgery is efficacious in producing significant and durable weight loss, improving obesity-related comorbidities, and extending survival, the U.S. healthcare system should examine ways to improve access to this treatment for obesity.     

Metabolic bone disease after gastric bypass surgery for obesity

BACKGROUND: The popularity of gastric bypass surgery for treatment of morbid obesity has been increasing in recent years. Osteomalacia and osteoporosis are commonly observed in patients who have had partial gastric resections for treatment of peptic ulcer disease. Recently, we encountered four patients with previous gastric bypass surgery who had metabolic bone disease similar to that reported in the older literature in patients who had partial gastrectomies. METHODS: Review of clinical data of four patients who developed osteomalacia and osteoporosis 9 to 12 years after gastric bypass surgery for morbid obesity. RESULTS: All subjects were women, 43 to 58 years old. Three had Roux-en-Y gastric bypass, and the other had a biliopancreatic diversion 9 to 12 years prior to presentation. Weight loss averaged 41.8 kg. Patients reported fatigue, myalgias, and arthralgias. They had symptoms for many months or years before the correct diagnosis was established. All were osteopenic or osteoporotic with hypocalcemia, very low or undetectable 25-hydroxyvitamin D levels, secondary hyperparathyroidism, increased 1,25-dihydroxyvitamin D levels, and increased serum alkaline phosphatase. CONCLUSIONS: Relatively little has been published in the general medical literature about this postoperative complication of bariatric surgery. Yet, nearly all patients after bariatric surgery will receive their long-term follow-up from a primary care physician. Physicians and patients need to be aware of this complication and take measures to identify and prevent it.     

Complications of bariatric surgery: Dumping syndrome,reflux and vitamin deficiencies

Bariatric surgical procedure are increasingly and successfully applied in the treatment of morbid obesity. Nevertheless, these procedures are not devoid of potential long-term complications. Dumping syndrome may occur after procedures involving at least partial gastric resection or bypass, including Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy. Diagnosis is based on clinical alertness and glucose tolerance testing. Treatment may involve dietary measures, acarbose and somatostatin analogues, or surgical reintervention for refractory cases. Gastro-esophageal reflux disease (GERD) can be aggravated by vertical banded gastroplasty and sleeve gastrectomy procedures, but pre-existing GERD may improve after RYGB and with adjustable gastric banding. Nutrient deficiencies constitute the most important long-term complications of bariatric interventions, as they may lead to haematological, metabolic and especially neurological disorders which are not always reversible. Malabsorptive procedures, poor postoperative nutrient intake, recurrent vomiting and poor compliance with vitamin supplement intake and regular follow-up are important risk factors. Preoperative nutritional assessment and rigourous postoperative follow-up plan with administration of multi-vitamin supplements and assessment of serum levels is recommended in all patients.     

Hypoglycaemia following gastric bypass surgery—diabetes remission in the extreme?

Postprandial hypoglycaemia is increasingly recognised as a complication of gastric bypass surgery. While post-bypass hypoglycaemia is often responsive to dietary modification, a subset of individuals develop life-threatening neuroglycopenia, with loss of consciousness, seizures and motor vehicle accidents. Such patients require complex nutritional and medical management strategies to reduce postprandial insulin secretion and stabilise glucose excursions, using medications including acarbose, octreotide and diazoxide, and frequent monitoring of glucose values. In an article in this issue of Diabetologia, nationwide registry data from Sweden were used to assess the frequency of severe hypoglycaemia and potentially related diagnoses (e.g. confusion, syncope, seizures, accidental death) following obesity surgery. Relative risk of hypoglycaemia and related diagnoses were two- to sevenfold higher in the post-gastric bypass population, but absolute risk was small. While these data underscore that hypoglycaemia is an important complication of gastric bypass, many questions regarding frequency, pathogenesis and optimal therapy remain unanswered. Given that hypoglycaemia is usually evaluated in the outpatient setting, more precise assessments of hypoglycaemia frequency will require prospective longitudinal studies in post-bypass cohorts. Until such data are available, practitioners should have a higher awareness of symptoms consistent with neuroglycopenia in patients with a history of bariatric surgery. Understanding the beneficial and challenging metabolic consequences of bariatric surgery is a key imperative for the diabetes community, as such data may yield novel insights into mechanisms by which bariatric surgery can lead to diabetes remission.     

Endoscopic treatment: The past,the present and the future

The obesity epidemic asks for an active involvement of gastroenterologists: many of the co-morbidities associated with obesity involve the gastrointestinal tract; a small proportion of obese patients will need bariatric surgery and may suffer from surgical complications that may be solved by minimally invasive endoscopic techniques; and finally, the majority will not be eligible for bariatric surgery and will need some other form of treatment. The first approach should consist of an energy-restricted diet, physical exercise and behaviour modification, followed by pharmacotherapy. For patients who do not respond to medical therapy but are not or not yet surgical candidates, an endoscopic treatment might look attractive. So, endoscopic bariatric therapy has a role to play either as an alternative or adjunct to medical treatment. The different endoscopic modalities may vary in mechanisms of action: by gastric distension and space occupation, delayed gastric emptying, gastric restriction and decreased distensibility, impaired gastric accommodation, stimulation of antroduodenal receptors, or by duodenal exclusion and malabsorption. These treatments will be discussed into detail.     

Megaloblastic anemia after gastric bypass for obesity

A megaloblastic anemia occurred in a middle-aged woman 6 years after a gastric bypass performed for obesity. Marked deficiencies of both vitamin B₁₂ and folic acid were demonstrated. The Schilling test revealed that the vitamin B₁₂ deficiency was due primarily to inadequate intrinsic factor. Vitamin and mineral deficiencies are relatively common long-term complications in gastric bypass patients, and result from multiple factors including restricted food intake, inadequate gastric digestion, and inadequate intrinsic factor. Bypass patients should receive vitamin-mineral supplements routinely and should have long-term periodic clinical and laboratory evaluation in order to prevent late hematological complications.     

Molecular insights from bariatric surgery

Bariatric surgical procedures have become important therapeutic options for treatment of morbid obesity in both adults and adolescents co-morbidities of obesity such as glucose intolerance, type 2 diabetes (T2DM), metabolic syndrome, steatohepatitis, hyperlipidemia and cardiovascular disease. These co-morbidities of obesity have significant impacts on the overall quality of life of the individual and our society at large. Roux-en-Y gastric bypass (RYGB) and the relatively newer procedures of gastric banding (GB) and vertical sleeve gastrectomy (VSG) have proven to be efficacious in achieving rapid weight loss and reversing the comorbidities of obesity. Unfortunately, bariatric procedures are not without risks including micronutrient deficiency, failure to maintain lost weight, and mortality. Further, the resolution of T2DM has long been understood to precede weight loss, and this finding provides important clues about the physiologic underpinnings of the observation. In order to design more effective, safe, and widely available therapeutics for obesity, important and highly relevant questions need to be addressed regarding mechanisms behind the weight-loss-independent benefits of bariatric surgical procedures. This review will provide an overview of the molecular changes occurring across all biological systems after bariatric surgery including the changes in hepatic, adipocyte and gut derived signals after surgery. We will also discuss existing literature regarding the weight-loss-independent metabolic benefits including improvement in insulin sensitivity and central nervous system integration of these signals.     

Multivitamin prophylaxis in prevention of post-gastric bypass vitamin and mineral deficiencies.

One hundred forty patients were followed for a mean 24.2 months after gastric bypass. Postop multivitamin (MV) prophylaxis was recommended for all patients and 90 of 140 patients (64 percent) were regularly compliant. Deficiencies in iron, vitamin B-12 or folate were recognized in 88 of 140 patients (63 percent). Thirty of 45 patients (67 percent) with iron deficiency developed anemia. Forty-three of the 52 patients who did not have deficiencies were regularly taking MV vs 47 of 88 patients who developed deficiencies (P less than 0.001). MV prophylaxis was successful in preventing folate (P less than or equal to 0.05) and vitamin B-12 deficiencies (P less than or equal to 0.02) but did not prevent development of iron deficiency or subsequent anemia. There was no correlation between taking prescribed supplements and resolution of either iron deficiency of anemia. B-12 and folate supplements corrected deficiencies in 73 percent of cases. We conclude that oral MV prophylaxis is useful in preventing folate and B-12 deficiency after gastric bypass. Additional prophylactic iron supplements should be provided for women to prevent iron deficiency and associated anemia.     

Oral drug therapy following bariatric surgery: an overview of fundamentals,literature and clinical recommendations

Bariatric surgery is the most effective solution for severe obesity and obesity with comorbidities, and the number of patients going through bariatric surgery is rapidly and constantly growing. The modified gastrointestinal anatomy of the patient may lead to significant pharmacokinetic alterations in the oral absorption of drugs after the surgery; however, because of insufficient available literature and inadequate awareness of the medical team, bariatric surgery patients may be discharged from the hospital with insufficient instructions regarding their medication therapy. In this article, we aim to present the various mechanisms by which bariatric surgery may influence oral drug absorption, to provide an overview of the currently available literature on the subject, and to draw guidelines for the recommendations bariatric surgery patients should be instructed before leaving the hospital. To date, and until more robust data are published, it is essential to follow and monitor patients closely for safety and efficacy of their medication therapies, both in the immediate and distant time post‐surgery.     

Serum 25-Hydroxyvitamin D Levels After Bariatric Surgery

Vitamin D deficiency is common after Roux-en-Y gastric bypass surgery, as malabsorptive component of the procedure affects its absorption, and dietary intake is inadequate due to restricted postoperative diet. Obesity itself is associated with low 25-hydroxy vitamin D levels due to larger volume of distribution with increased body fat mass, and studies have confirmed the presence of fat-soluble vitamin D in human adipose tissue. Massive weight loss after gastric bypass surgery is associated with an increase in serum 25-hydroxy vitamin D levels; however, the effect is small, and thus supplementation remains the mainstay of treatment and prevention of vitamin D deficiency in this population. Higher doses of vitamin D are often required, as most patients remain obese after bariatric surgery, and its absorption is reduced. Guidelines recommended supplementing bariatric patients with at least 3,000 IU per day of vitamin D, while doses as high as 50,000 IU 1–3 times weekly may be required in some patients.     

Surgical Management of Obesity

Obesity continues to plague our society in epidemic proportions. Surgery for morbid obesity is considered by many as the most effective therapy for this complex disorder. Today, multiple surgical procedures for the treatment of obesity are available. As with most procedures, there are benefits and risks associated with open and laparoscopic gastric bypass surgery, as well as with laparoscopic adjustable gastric banding and partial biliopancreatic bypass with a duodenal switch. The risks and complications associated with bariatric surgery may be serious and in some cases life threatening. However, surgery for obesity has shown remarkable results in helping patients to achieve significant long-term weight control. In addition, it is associated with improvement and often resolution of co-morbid conditions, including type 2 diabetes mellitus, systemic hypertension, obesity hypoventilation, sleep apnea, venous stasis disease, pseudotumor cerebri, polycystic ovary syndrome, complications of pregnancy and delivery, gastroesophageal reflux disease, stress urinary incontinence, degenerative joint disease, and non-alcoholic steatohepatitis.     

Bariatric Surgery and Bone Loss: Do We Need to Be Concerned?

Despite significant improvement in weight and comorbid conditions, there is growing evidence that bariatric surgery may exert a negative effect on the skeleton. This review has focused on the impact of bariatric surgery on bone health, with the concern that bariatric surgery may increase skeletal fragility and fracture risk by accelerating bone loss. We have highlighted studies evaluating changes in bone metabolism after three commonly performed bariatric procedures including laparoscopic adjustable gastric banding, Roux-en-Y gastric bypass surgery and increasingly popular sleeve gastrectomy. This review has also discussed some of the technical issues faced in measuring bone in obese populations and during dynamic weight loss. There is limited evidence regarding potential mechanisms for the reported observations of increased bone turnover and/or bone loss after bariatric surgery. We have reviewed the evidence surrounding potential factors affecting bone health in bariatric patients such as rapid weight loss per se, nutritional deficiencies, effects of fat-derived adipokines and gut-derived appetite-regulatory hormones. Future prospective long-term cohort studies are needed to define how to quantify bone loss in individuals with obesity, particularly following massive weight loss, and for how long the bone changes continue. These studies will help clarify any negative clinical consequences of these changes, including future fracture risk in this unique group of patients.     

Medical complications of bariatric surgery: focus on malabsorption and dumping syndrome

Gastroenterologists increasingly see patients with symptoms after bariatric surgery. A number of gastrointestinal or extra-gastrointestinal symptoms should raise the suspicion of malabsorption or dumping syndrome. Little is known about long-term consequences of disordered intestinal anatomy and physiology resulting from bariatric surgical procedures. The latency phase of clinical problems is unknown, but may potentially be long, and postoperative courses over many decades have to be considered regarding the consequences of surgical alterations of gastrointestinal structure and function. Long-term nutritional requirements in patients with bariatric procedures are incompletely understood. This review focuses on the pathophysiology of long-limb Roux-en-Y gastric bypass (RYGB) because it has become the most common bariatric procedure in many parts of the world. Although several potential mechanisms for nutritional deficiencies after RYGB like deficiency of dietary intake, lack of gastric secretions, exclusion of proximal duodenum and jejunum, or asynergia between food bolus and biliopancreatic secretions have been postulated, it was only very recently that in-depth studies have been carried out to measure the extent to which the long-limb RYGB causes malabsorption. In order to improve care for these patients, specialists who are trained in understanding pathophysiological changes in digestion and absorption after bariatric surgery and who recognize and treat clinical symptoms and nutritional deficits after bariatric surgery are needed. In addition, clinical researchers should take advantage of the experimental setups provided by standardized surgical procedures, and scientific societies should design courses and scientific meetings which combine the expertise in gastroenterology, surgery and nutrition.     

Cardiovascular benefits of bariatric surgery in morbidly obese patients

Morbid obesity is associated with increased morbidity and represents a major healthcare problem with increasing incidence worldwide. Bariatric surgery is considered an effective option for the management of morbid obesity. We searched MEDLINE, Current Contents and the Cochrane Library for papers published on bariatric surgery in English from 1 January 1990 to 20 July 2010. We also manually checked the references of retrieved articles for any pertinent material. Bariatric surgery results in resolution of major comorbidities including type 2 diabetes mellitus, hypertension, dyslipidemia, metabolic syndrome, non‐alcoholic fatty liver disease, nephropathy, left ventricular hypertrophy and obstructive sleep apnea in the majority of morbidly obese patients. Through these effects and possibly other independent mechanisms bariatric surgery appears to reduce cardiovascular morbidity and mortality. Laparoscopic Roux‐en‐Y gastric bypass (LRYGB) appears to be more effective than laparoscopic adjustable gastric banding (LAGB) in terms of weight loss and resolution of comorbidities. Operation‐associated mortality rates after bariatric surgery are low and LAGB is safer than LRYGB. In morbidly obese patients bariatric surgery is safe and appears to reduce cardiovascular morbidity and mortality.     

Syndrome multicarentiel catastrophique post bypass gastrique

IntroductionBariatric surgery is a very effective treatment for obesity. After gastric bypass, micronutrient deficiencies frequently occur which can have dramatic consequences.Case reportWe report the case of a 55-year-old woman who was admitted for psychomotor retardation, bilateral leg pitting edema and psoriasis-like rash that had been ongoing for 3 months. Pancytopenia, encephalopathy and heart failure rapidly occurred leading to multiorgan dysfunction syndrome and death. We retrospectively identified severe selenium deficiency with possible secondary cardiomyopathy, niacin deficiency resulting in pellagrous encephalopathy with skin lesions and gelatinous transformation of bone marrow.ConclusionMicronutrient deficiency should systematically be assessed when new symptoms occur in a patient with a history of bariatric surgery. Selenium deficiency should be considered in the presence of any heart failure in this context.     

Nutritional and metabolic complications of bariatric surgery

Bariatric surgery is an effective treatment for patients with clinically severe obesity. In addition to significant weight loss, it is also associated with improvements in comorbidities. Unfortunately, bariatric surgery also has the potential to cause a variety of nutritional and metabolic complications. These complications are mostly due to the extensive surgically induced anatomical changes incurred by the patient's gastrointestinal tract, particularly with roux-en-Y gastric bypass and biliopancreatic diversion. Complications associated with vertical banded gastroplasty are mostly due to decreased intake amounts of specific nutrients. Macronutrient deficiencies can include severe protein-calorie malnutrition and fat malabsorption. The most common micronutrient deficiencies are of vitamin B12, iron, calcium, and vitamin D. Other micronutrient deficiencies that can lead to serious complications include thiamine, folate, and the fat-soluble vitamins. Counseling, monitoring, and nutrient and mineral supplementation are essential for the treatment and prevention of nutritional and metabolic complications after bariatric surgery.     

Anaemia in patients with self-reported use of iron supplements in the BAriatric surgery SUbstitution and nutrition study: A prospective cohort study

Background and aimsAfter bariatric surgery, micronutrient deficiencies may lead to anaemia. To prevent post-operative deficiencies, patients are recommended lifelong micronutrient supplementation. Studies investigating the effectiveness of supplementation to prevent anaemia after bariatric surgery are scarce. This study aimed to investigate the relationship between nutritional deficiencies and anaemia in patients who report use of supplementation two years after bariatric surgery versus patients who do not.Methods and resultsObese (BMI≥35 kg/m²) individuals (n = 971) were recruited at Sahlgrenska University Hospital in Gothenburg, Sweden between 2015 and 2017. The interventions were Roux-en-Y gastric bypass (RYGB), n = 382, sleeve gastrectomy (SG), n = 201, or medical treatment (MT), n = 388. Blood samples and self-reported data on supplements were collected at baseline and two years post treatment. Anaemia was defined as haemoglobin <120 g/L for females and <130 g/L for males. Standard statistical methods, including a logistic regression model and a machine learning algorithm, were used to analyse data. The frequency of anaemia increased from baseline in patients treated with RYGB (3·0% vs 10·5%; p < 0·05). Neither iron-dependent biochemistry nor frequency of anaemia differed between participants who reported use of iron supplements and those who did not at the two-year follow-up. Low preoperative level of haemoglobin and high postoperative percent excessive BMI loss increased the predicted probability of anaemia two years after surgery.ConclusionThe results from this study indicate that iron deficiency or anaemia may not be prevented by substitutional treatment per current guidelines after bariatric surgery and highlights there is reason to ensure adequate preoperative micronutrient levels.Trial registration: March 03, 2015; NCT03152617.