Biliopancreatic diversion requires multiple vitamin and micronutrient adjustments within 2 years of surgery

Hypoabsorption in Bariatric Surgery: Is the Benefit Worth the Risk?

Metabolic and bariatric surgery has been well described in the existing literature to be an effective and safe modality for weight loss in patients with obesity. Recently, hypoabsorptive procedures such as one-anastomosis gastric bypass (OAGB), biliopancreatic diversion with duodenal switch (BPD-DS), and single-anastomosis duodenoileostomy with sleeve (SADI-S) have gained traction, particularly among patients with severe obesity. These procedures combine restrictive and hypoabsorptive mechanisms, resulting in significant and sustainable weight loss, especially in those with severe obesity and associated comorbidities. However, the risk of malnutrition and nutritional deficiency following these procedures has been a deterrent for surgeons in their adoption. This review evaluates the existing literature on the safety, efficacy, and long-term outcomes of OAGB, BPD-DS, and SADI-S. While these hypoabsorptive procedures represent highly effective options for treating obesity, the associated nutritional complications necessitate the need for long-term follow-up and supplementation and highlight the need for careful patient selection.

Preventing and Managing Pre- and Postoperative Micronutrient Deficiencies: A Vital Component of Long-Term Success in Bariatric Surgery

Bariatric surgery (BS) is an effective treatment for severe obesity and its related comorbidities, such as type 2 diabetes and hypertension. However, the anatomical and physiological changes associated with these procedures significantly increase the risk of preoperative and postoperative micronutrient deficiencies, which can lead to severe complications such as anemia, osteoporosis, and neurological disorders. This narrative review examines the prevalence and clinical implications of micronutrient deficiencies in BS patients, as well as evidence-based strategies for their prevention and management. The most common deficiencies include iron, vitamin B12, folate, calcium, vitamin D, and fat-soluble vitamins (A, E, and K). Procedures with a hypoabsorptive component, such as Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion with duodenal switch (BPD/DS), pose higher risks of deficiencies compared to restrictive procedures like sleeve gastrectomy (SG). Effective strategies involve the preoperative correction of deficiencies, continuous monitoring, and tailored supplementation. However, long-term adherence to supplementation tends to decrease over time, influenced by behavioral and socioeconomic factors. Hence, preventing and managing micronutrient deficiencies are crucial for the long-term success of BS. While current guidelines provide valuable recommendations, many are based on low-certainty evidence, underscoring the need for more robust studies. A multidisciplinary approach, combined with innovative strategies, such as telemedicine, can enhance adherence and achieve sustainable clinical outcomes.

Bariatrisch-metabolische Operationstechniken

Bariatrisch-metabolische Operationen gelten als die effektivste Therapiemöglichkeit der morbiden Adipositas. In Langzeitstudien konnten sehr gute Erfolge bei der Reduktion des Übergewichts und bei der Behandlung Adipositas-assoziierter Komorbiditäten (u. a. arterielle Hypertonie, Diabetes mellitus Typ 2) gezeigt werden. Die bariatrischen Operationstechniken beruhen auf dem Wirkungsprinzip der Restriktion und Malabsorption. Die damit verbundenen metabolischen Effekte, die z. T. unabhängig vom Gewichtsverlust und der Kalorienreduktion schon früh postoperativ einsetzen, werden derzeit intensiv beforscht. Die am häufigsten angewandten restriktiven Verfahren sind Schlauchmagen, Magenband, Magenfaltung und Magenballon. Beim Magenbypass, der biliopankreatischen Diversion (mit und ohne duodenalem Switch) und dem „single anastomosis duodenal-ileal-bypass“ mit Sleeve werden die Wirkprinzipien kombiniert. Die Eingriffe werden üblicherweise laparoskopisch durchgeführt und haben akzeptable Komplikationsraten. Postoperativ sind lebenslange Stoffwechselkontrollen und Substitution mit Vitaminen und Spurenelementen (insbesondere bei malabsorptiven Verfahren) erforderlich, um einer Malnutrition vorzubeugen.

Malnutrition Following One-Anastomosis Gastric Bypass: a Systematic Review

Severe malnutrition following one-anastomosis gastric bypass (OAGB) remains a concern. Fifty studies involving 49,991 patients were included in this review. In-hospital treatment for severe malnutrition was needed for 0.9% (n = 446) of patients. Biliopancreatic limb (BPL) length was 150 cm in five (1.1%) patients, > 150 cm in 151 (33.9%), and not reported in 290 (65%) patients. OAGB was revised to normal anatomy in 126 (28.2%), sleeve gastrectomy in 46 (10.3%), Roux-en-Y gastric bypass in 41 (9.2%), and shortening of BPL length in 17 (3.8%) patients. One hundred fifty-one (33.8%) patients responded to treatment; ten (2.2%) did not respond and was not reported in 285 (63.9%) patients. Eight (0.02%) deaths were reported. Standardisation of the OAGB technique along with robust prospective data collection is required to understand this serious problem.

Vitamin D status and supplementation before and after Bariatric Surgery: Recommendations based on a systematic review and meta-analysis

Bariatric surgery is associated with a postoperative reduction of 25(OH) vitamin D levels (25(OH)D) and with skeletal complications. Currently, guidelines for 25(OH)D assessment and vitamin D supplementation in bariatric patients, pre- and post-surgery, are still lacking. The aim of this work is to analyse systematically the published experience on 25(OH)D status and vitamin D supplementation, pre- and post-surgery, and to propose, on this basis, recommendations for management. Preoperatively, 18 studies including 2,869 patients were evaluated. Prevalence of vitamin D insufficiency as defined by 25(OH)D < 30 ng/mL (75 nmol/L) was 85%, whereas when defined by 25(OH)D < 20 ng/mL (50 nmol/L) was 57%. The median preoperative 25(OH)D level was 19.75 ng/mL. After surgery, 39 studies including 5,296 patients were analysed and among those undergoing either malabsorptive or restrictive procedures, a lower rate of vitamin D insufficiency and higher 25(OH)D levels postoperatively were observed in patients treated with high-dose oral vitamin D supplementation, defined as ≥ 2,000 IU/daily (mostly D3-formulation), compared with low-doses (< 2,000 IU/daily). Our recommendations based on this systematic review and meta-analysis should help clinical practice in the assessment and management of vitamin D status before and after bariatric surgery. Assessment of vitamin D should be performed pre- and postoperatively in all patients undergoing bariatric surgery. Regardless of the type of procedure, high-dose supplementation is recommended in patients after bariatric surgery.

Single Versus Double Anastomosis Duodenal Switch in the Management of Obesity: A Meta-analysis and Systematic Review

BACKGROUND

Biliopancreatic diversion with duodenal switch (BPD-DS) is an effective yet technically challenging bariatric surgery with many complications. Alternatively, single anastomosis duodenal-ileal bypass with sleeve gastrectomy (SADI-S) was recently introduced as a simplified bariatric procedure. This meta-analysis aimed to assess the safety and efficacy of SADI-S compared with BPD-DS in the management of patients with obesity.

METHODS

Cochrane, Embase, PubMed, Scopus, and Web of Science were searched for articles from their inception to May 2022 by 2 independent reviewers using the Preferred Reporting Items for Systematic Reviews and Meta-analysis system. The review was registered prospectively with PROSPERO (CRD42022333521).

RESULTS

From 123 studies screened, 6 studies met the eligibility criteria, with a total of 1847 patients with obesity undergoing either SADI-S (n=818) or BPD-DS (n=1029). Preoperative body mass index was similar between the 2 groups, and the BPD-DS group had a greater % excess body mass index loss (EBMIL) (MD=-10.16%, 95% confidence interval: -11.80, -8.51, I2=0%) at 2 years compared with the SADI-S group. There was no difference observed in preoperative comorbidities and remission, including diabetes, hypertension, and dyslipidemia between SADI-S and BPD-DS cohorts. Compared with BPD-DS, SADI-S had shorter hospital stays (MD=-1.36 d, 95% CI: -2.39, -0.33, I2=86%), and fewer long-term (>30 d) complications (OR=0.56, 95% CI: 0.42, 0.74, I2=20%). Conversely, among nutritional deficiency outcomes, the SADI-S group had few patients with abnormal vitamin D (OR=0.51, 95% CI: 0.36, 0.72, I2=0%) values than the BPD-DS group.

CONCLUSIONS

SADI-S has shown to be a possible alternative treatment option to BPD-DS in managing patients with obesity. Despite the promising results, further randomized controlled studies with more extended follow-up periods are necessary to ascertain the safety and efficacy of the treatment.

Safety of biliopancreatic diversion with duodenal switch in patients with body mass index less than 50 kg/m2

INTRODUCTION

Biliopancreatic diversion with duodenal switch (BPD-DS) has often been reserved for patients with BMI > 50 kg/m². We aim to assess the safety of BPD-DS in patients with morbid obesity (BMI ³35 kg/m² and < 50 kg/m²) using a 150-cm common channel (CC), 150-cm Roux limb, and 60-fr bougie.

METHODS

A retrospective review was performed on patients with a BMI < 50 mg/k² who underwent a BPD-DS in 2016-2019 at a single institution. Limb lengths were measured with a laparoscopic instrument with minimal tension. Sleeve gastrectomy was created with 60-fr bougie. Variables were compared using paired t test, Chi-square analysis or repeated measures ANOVA where appropriate.

RESULTS

Forty-five patients underwent BPD-DS. CC lengths and Roux limb lengths were 158 ± 20 cm and 154 ± 18 cm, respectively. Preoperative BMI was 44.9 ± 2.3 kg/m² and follow-up was 2.7 ± 1.4 years. One patient required reoperation for bleeding and died from multiorgan failure and delayed sleeve leak. There was 1 (2.2%) readmission for contained anastomotic leak and 2 ED visits (4.5%) within 30 days. There were no marginal ulcers, limb length revisions, or need for parental nutrition. Percent excess weight loss was 67.2 ± 19.7%. 88.9% (N = 8), 86.6% (N = 13), and 55.5% (N = 5) of patients had resolution or improvement of their diabetes mellitus type II, hypertension, and hyperlipidemia, respectively. 40% (N = 4) of patients had resolution of their gastroesophageal reflux disease (GERD) and 11.4% (N = 5) developed de novo GERD. 32% (N = 14) of patients had vitamin D deficiency and 25% (N = 11) experienced zinc deficiency.

CONCLUSION

BPD-DS may be considered in patients with BMI < 50 kg/m² with 150-cm CC, 150-cm Roux limb, and a 60-fr bougie sleeve gastrectomy. There was sustained weight loss and no protein calorie malnutrition, but Vitamin D and zinc deficiency remained a challenge. Careful patient selection and proper counseling of the risks and benefits are necessary.

Improving vitamin D status in bariatric surgery subjects with monthly high-dose ergocalciferol

Background: Vitamin D insufficiency is common before and after bariatric surgery. Optimal supplementation to treat vitamin D insufficiency is not clearly defined. Objective: Determine if serum 25 (OH) D levels improve by the consumption of an additional monthly ergocalciferol supplement by subjects after bariatric surgery. Study design: Thirty-two subjects were randomly divided to receive an additional 100,000 IUs of ergocalciferol monthly after bariatric surgery (n=10) or standard level vitamin D supplement after bariatric surgery (n=22). Serum 25 (OH) D, calcium, and hemoglobin A1c levels were measured preoperatively and one year after bariatric surgery. Results: Mean changes in BMI at 1-year post-operation was -18.12±6.46 kg/m² in the control group versus -18.84±4.7 kg/m²; p=0.638 in the vitamin D group. One year after bariatric surgery, the mean changes from baseline in vitamin D levels were 2.69±9.4 and 12.4±17.0 ng/mL in control and intervention groups, respectively. The treated group showed a marginally higher mean increase in Vitamin D than the control group, p=0.059. Other mean changes at 1-year post-surgery that were not significantly different include calcium -0.264±0.45 and -0.21±0.509 mg/dl in control and intervention groups, respectively and Hgb A1c -1.0±1.21 and -0.95±0.071% in control and intervention groups, respectively. Conclusion: This study showed 100,000 IUs ergocalciferol once a month is a safe and effective treatment for vitamin D insufficiency in most patients having bariatric surgery.

Iron supplementation following bariatric surgery: A systematic review of current strategies

Iron deficiency (ID) and iron deficiency anemia (IDA) are common following bariatric surgery; however, there are limited standardized treatment recommendations for their management. The purpose of this study was to review the current strategies for iron supplementation following bariatric surgery and assess their relative efficacy in managing ID and IDA. MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched to January 2021. Primary outcomes of interest were prevention or improvement in ID or IDA with iron supplementation. Forty-nine studies with 12,880 patients were included. Most patients underwent Roux-en-Y gastric bypass (61.9%). Iron supplementation was most commonly administered orally for prevention of ID/IDA and was effective in 52% of studies. Both IV and oral iron were given for treatment of ID/IDA. Fifty percent (3/6) of the oral and 100% (3/3) of the IV supplementation strategies were effective at treating ID. Iron supplementation strategies employed following bariatric surgery are highly variable, and many do not provide sufficient iron to prevent the development of ID and IDA, potentially due to poor patient adherence. Further high-quality prospective trials, particularly comparing intravenous and oral iron, are warranted in order to determine the ideal dosage, route, and duration of iron supplementation.

Revisional Laparoscopic SADI-S vs. Duodenal Switch Following Failed Primary Sleeve Gastrectomy: a Single-Center Comparison of 101 Consecutive Cases

BACKGROUND

Single-anastomosis duodeno-ileal bypass (SADI-S) is being proposed for obese patients with insufficient weight loss or weight regain after sleeve gastrectomy (SG), but limited information is available. The purpose of this study is to assess the safety and efficacy of SADI-S as a revisional surgery after SG, compared with standard duodenal switch (DS).

METHODS

Unicentric cohort study including all patients submitted to SADI-S and DS after failed SG in a high-volume institution, between 2008 and 2020.

RESULTS

Forty-six patients submitted to SADI-S and 55 to DS were included, 37.2 and 41.5 months after SG (p = 0.447), with initial BMI of 56.2 vs. 56.6 (p = 0.777) and 39.2 vs. 39.7 before revisional surgery (p = 0.675). All surgeries were laparoscopic. Clavien-Dindo > II complication rate was 6.5% for SADI-S and 10.9% for DS (p = 0.095), with no 90-day mortality. Follow-up at 2 years was available for 38 SADI-S' and 38 DS' patients, with total weight loss of 35.3% vs. 41.7% (p = 0.009), and excess weight loss 64.1% vs. 75.3% (p = 0.014). Comorbidities resolution for SADI-S and DS was: 44.4% vs. 76.9% for diabetes (p = 0.029) and 36.4% vs. 87.5% for hypertension (p = 0.006); with no differences for resolution of dyslipidemia (72.7% vs. 88.9%, p = 0.369) and obstructive sleep apnea (93.3% vs. 91.7%, p = 0.869). DS' patients required more extra nutritional supplementation. Three SADI-S patients needed conversion to DS, two for biliary reflux and one for weight regain.

CONCLUSION

After a failed SG, revisional DS permits better weight control and diabetes and hypertension resolution than SADI-S, at the expense of higher supplementation needs.

Nutritional consequences of bariatric surgery - prevention, detection and management

PURPOSE OF REVIEW

Bariatric surgery is an effective treatment option for severe and complex obesity; however, those who undergo such surgery need access to nutritional monitoring and vitamin and mineral supplementation to avoid the development of nutritional deficiencies.

RECENT FINDINGS

The British Obesity and Metabolic Surgery Society and the American Society for Metabolic and Bariatric Surgery have recently updated their recommendations on preoperative and postoperative nutritional monitoring and supplementation. There is a growing interest in the more malabsorptive procedures that are associated with an increased risk of nutritional deficiencies. Nutritional monitoring and prevention of nutritional deficiencies are discussed.Long-term follow-up that includes annual nutritional monitoring and access to a dietetic annual review is recommended; however, in the United Kingdom, many bariatric surgery centres are only commissioned to provide 2 years of follow-up, after which care is transferred to the general practitioner. Consideration should be given to developing shared care models for aftercare and also for the aftercare of malabsorptive procedures to remain with specialist centres.

SUMMARY

Bariatric surgery is a safe and effective treatment option for severe and complex obesity. It is essential that patients have access to lifelong nutritional monitoring adjustment of vitamin and mineral supplements to prevent nutritional issues.

Recommendations for nutritional care after bariatric surgery: Recommendations for best practice and SOFFCO-MM/AFERO/SFNCM/expert consensus

Nutritional care after bariatric surgery is an issue of major importance, especially insofar as risk of deficiency has been extensively described in the literature. Subsequent to the deliberations carried out by a multidisciplinary working group, we are proposing a series of recommendations elaborated using the Delphi-HAS (official French health authority) method, which facilitates the drawing up of best practice and consensus recommendations based on the data of the literature and on expert opinion. The recommendations in this paper pertain to dietary management and physical activity, multivitamin and trace element supplementation and the prevention and treatment of specific deficiencies in vitamins B1, B9, B12, D and calcium, iron, zinc, vitamins A, E and K, dumping syndrome and reactive hypoglycemia.

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.

Recommendations Based on Evidence by the Andalusian Group for Nutrition Reflection and Investigation (GARIN) for the Pre- and Postoperative Management of Patients Undergoing Obesity Surgery

In order to develop evidence-based recommendations and expert consensus for nutrition management of patients undergoing bariatric surgery and postoperative follow-up, we conducted a systematic literature search using PRISMA methodology plus critical appraisal following the SIGN and AGREE-II procedures. The results were discussed among all members of the GARIN group, and all members answered a Likert scale questionnaire to assess the degree of support for every recommendation. Patients undergoing bariatric surgery should be screened preoperatively for some micronutrient deficiencies and treated accordingly. A VLCD (Very Low-Calorie Diet) should be used for 4-8 weeks prior to surgery. Postoperatively, a liquid diet should be maintained for a month, followed by a semi-solid diet also for one month. Protein requirements (1-1.5 g/kg) should be estimated using adjusted weight. Systematic use of specific multivitamin supplements is encouraged. Calcium citrate and vitamin D supplements should be used at higher doses than are currently recommended. The use of proton-pump inhibitors should be individualised, and vitamin B12 and iron should be supplemented in case of deficit. All patients, especially pregnant women, teenagers, and elderly patients require a multidisciplinary approach and specialised follow-up. These recommendations and suggestions regarding nutrition management when undergoing bariatric surgery and postoperative follow-up have direct clinical applicability.

The Effects of Bariatric Surgery on Islet Function, Insulin Secretion, and Glucose Control

Although bariatric surgery was developed primarily to treat morbid obesity, evidence from the earliest clinical observations to the most recent clinical trials consistently demonstrates that these procedures have substantial effects on glucose metabolism. A large base of research indicates that bariatric surgeries such as Roux-en-Y gastric bypass (RYGB), vertical sleeve gastrectomy (VSG), and biliopancreatic diversion (BPD) improve diabetes in most patients, with effects frequently evident prior to substantial weight reduction. There is now unequivocal evidence from randomized controlled trials that the efficacy of surgery is superior to intensive life-style/medical management. Despite advances in the clinical understanding and application of bariatric surgery, there remains only limited knowledge of the mechanisms by which these procedures confer such large changes to metabolic physiology. The improvement of insulin sensitivity that occurs with weight loss (e.g., the result of diet, illness, physical training) also accompanies bariatric surgery. However, there is evidence to support specific effects of surgery on insulin clearance, hepatic glucose production, and islet function. Understanding the mechanisms by which surgery affects these parameters of glucose regulation has the potential to identify new targets for therapeutic discovery. Studies to distinguish among bariatric surgeries on key parameters of glucose metabolism are limited but would be of considerable value to assist clinicians in selecting specific procedures and investigators in delineating the resulting physiology. This review is based on literature related to factors governing glucose metabolism and insulin secretion after the commonly used RYGB and VSG, and the less frequently used BPD and adjustable gastric banding.

Serum Parathyroid Hormone and 25-Hydroxyvitamin D Concentrations Before and After Biliopancreatic Diversion

BACKGROUND

Biliopancreatic diversion with duodenal switch (BPD-DS) decreases vitamin D and calcium absorption, which may result in secondary hyperparathyroidism. This study aimed at evaluating the prevalence of vitamin D deficiency and secondary hyperparathyroidism before and after BPD-DS.

METHODS

A retrospective analysis of patients who had undergone BPD-DS at a tertiary bariatric center between 2003 and 2010 and for whom simultaneous measurements of serum 25-hydroxyvitamin D and parathyroid hormone were available within 5 years post-op was performed. The prevalence of vitamin D deficiency (< 20 ng/ml) and secondary hyperparathyroidism (> 65 pg/mL) at different time points was calculated.

RESULTS

Included were 1436 patients (mean ± SD, age 42.7 ± 10.4 years; BMI 51.5 ± 8.6 kg/m²; 69.8% women). Prevalence of vitamin D deficiency decreased up to 6-12 months after surgery (from 35.8% at baseline down to 6-9%) then rose progressively, plateauing at 15.5% after 36 months. Prevalence of hyperparathyroidism was 28.5% before surgery and rose progressively after surgery, reaching 68.6% at 5 years. Mean serum corrected calcium increased from 0 to 6 months then decreased up to 36 months. Preoperatively, the prevalence of hypocalcemia was 7.3%. It increased after 12 months, attaining 26.9% at 48 months.

CONCLUSIONS

Prevalence of vitamin D deficiency and secondary hyperparathyroidism is high before BPD-DS. Despite a low prevalence of vitamin D deficiency after surgery, prevalence of hyperparathyroidism increased steadily 1 year after surgery, preceded by a decrease in serum calcium. Factors explaining the high prevalence of secondary hyperparathyroidism after BPD-DS and its long-term impact on bone health should be addressed.

Metabolic surgery and iron homeostasis

Iron deficiency and anaemia after metabolic surgery, potentially modifiable nutritional complications, are becoming an increasing cause for concern as prevalence increases with time and there is limited evidence supporting the effectiveness of the current guidelines for prophylactic oral iron supplementation and treatment for deficiency. Abnormalities in iron nutrition predisposing to deficiency are common in severely obese patients, and the low-grade systemic inflammation, also common to these patients, reduces the effectiveness of oral iron supplementation. The surgical procedures result in alterations of foregut anatomy and physiology, which limit iron absorptive capacity and daily food intake. These alterations and the limited effects of oral iron supplementation explain the high prevalence of postoperative iron deficiency and anaemia. This review outlines current mechanisms concerning the pathogenesis of disordered iron nutrition in patients with severe obesity, current gaps in knowledge, and opportunities for quality improvement.

Transient osteoporosis of the hip after bariatric surgery

Transient osteoporosis is a rare manifestation of acute hip pain which typically resolves with weight-bearing restrictions and pain management. Our case report presents a patient who experienced atraumatic right hip pain a few weeks after an uncomplicated bariatric surgery and was diagnosed with transient osteoporosis of the hip. Her condition resolved after weeks of protected weight-bearing restrictions and nonsteroidal anti-inflammatories. Transient osteoporosis should be considered in the differential diagnosis of hip pain in patients who have undergone previous bariatric surgery.

Roux-en-Y Gastric Bypass Aggravates Vitamin A Deficiency in the Mother-Child Group

OBJECTIVE

The objectives of this study are to compare the nutritional status of vitamin A in women who previously underwent Roux-en-Y gastric bypass (RYGB) who became pregnant or did not, in the same period after surgery, and to assess its effects on mother and child health.

METHODOLOGY

A retrospective longitudinal study conducted with women who previously underwent RYGB, paired by age and BMI measured before surgery, divided into group 1 (G1) comprising 77 women who did not become pregnant and group 2 (G2) with 39 women in their third gestational trimester. Both groups were assessed before surgery (T0) and in the same interval after surgery: less than or equal to 1 year (T1) or over 1 year (T2), during a maximum of 2 years. Serum concentrations of retinol and β-carotene, night blindness (NB), and gestational and neonatal complications were investigated [urinary tract infection, iron deficiency anemia, hypertensive syndrome of pregnancy, dumping syndrome, birth weight, gestational age at birth (GAB), and correlation between weight and GAB]. Data were analyzed by the Statistical Package for Social Sciences 21.0 (p < 0.05).

RESULTS

RYGB reduced the serum levels of retinol and β-carotene, especially before the first postsurgical year. When associated with pregnancy, inadequacy rate was 55% higher in T1 and T2. Comparing G1 to G2, we noted that pregnancy in women undergoing RYGB can contribute to increased inadequacy of retinol and β-carotene, reaching a higher percentage of women with NB after 1 postsurgical year. High prevalence of pregnancy/neonatal complications was found in T1 and T2. NB was correlated with inadequacy of β-carotene.

CONCLUSION

Pregnancy after RYGB aggravates vitamin A deficiency, increases the percentage of NB cases, and can contribute to pregnancy and neonatal complications even in 1 postsurgical year.

Cirrhosis following single anastomosis duodeno-ileal switch: A case report

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We report a rare case of a liver cirrhosis in a patient who underwent single anastomosis duodenal switch procedure.

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We describe the possible presentation of the patient with a liver cirrhosis.

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Management of single anastomosis duodenal switch patients should include close monitoring of liver function.

Introduction

Single anastomosis duodeno-ileal switch (SADI-S) involves a single, loop duodeno-ileal anastomosis with omission of the traditional Roux-en-Y distal ileo-ileal anastomosis. Not much has been published on the complications of SADI-S.

Presentation of case

The patient is a 40 year-old male who underwent robot-assisted SADI-S three years prior. At the time of surgery, his body mass index (BMI) was 69 kg/m². His BMI was 31 kg/m² at the time of presentation. Computed tomography of the abdomen and pelvis showed a liver with a nodular appearance and moderate ascites throughout the abdomen and above the liver. Liver function showed AST 73 U/L, ALT 63 U/L, alkaline phosphatase 128 U/L, bilirubin 1.0 mg/dL, and albumin 2.8 g/dL. He underwent diagnostic and therapeutic paracentesis with removal of 6L of fluid that was negative for infection or malignant cells. Esophagogastroduodenoscopy showed grade I esophageal varices and diffuse mild gastritis.

Discussion

Mild hepatic dysfunction is common after biliopancreatic diversion and usually manifests as a temporary rise in liver enzymes that peak several months after surgery and normalize by one year. Cirrhosis and liver failure are rare sequelae that may develop at any time after surgery. Potential mechanisms include the absorption of hepatotoxic compounds from the bypassed small intestine in the context of bacterial overgrowth, protein malnutrition, and excessive free fatty acid mobilization causing steatosis and oxidative damage to hepatocytes.

Conclusion

Close laboratory monitoring is important after SADI-S in order to detect worsening hepatic dysfunction, which may occur many years after the surgery in the absence of other etiologies for liver failure.

Disturbed Vitamin A Metabolism in Non-Alcoholic Fatty Liver Disease (NAFLD)

Vitamin A is required for important physiological processes, including embryogenesis, vision, cell proliferation and differentiation, immune regulation, and glucose and lipid metabolism. Many of vitamin A’s functions are executed through retinoic acids that activate transcriptional networks controlled by retinoic acid receptors (RARs) and retinoid X receptors (RXRs).The liver plays a central role in vitamin A metabolism: (1) it produces bile supporting efficient intestinal absorption of fat-soluble nutrients like vitamin A; (2) it produces retinol binding protein 4 (RBP4) that distributes vitamin A, as retinol, to peripheral tissues; and (3) it harbors the largest body supply of vitamin A, mostly as retinyl esters, in hepatic stellate cells (HSCs). In times of inadequate dietary intake, the liver maintains stable circulating retinol levels of approximately 2 μmol/L, sufficient to provide the body with this vitamin for months. Liver diseases, in particular those leading to fibrosis and cirrhosis, are associated with impaired vitamin A homeostasis and may lead to vitamin A deficiency. Liver injury triggers HSCs to transdifferentiate to myofibroblasts that produce excessive amounts of extracellular matrix, leading to fibrosis. HSCs lose the retinyl ester stores in this process, ultimately leading to vitamin A deficiency. Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome and is a spectrum of conditions ranging from benign hepatic steatosis to non-alcoholic steatohepatitis (NASH); it may progress to cirrhosis and liver cancer. NASH is projected to be the main cause of liver failure in the near future. Retinoic acids are key regulators of glucose and lipid metabolism in the liver and adipose tissue, but it is unknown whether impaired vitamin A homeostasis contributes to or suppresses the development of NAFLD. A genetic variant of patatin-like phospholipase domain-containing 3 (PNPLA3-I148M) is the most prominent heritable factor associated with NAFLD. Interestingly, PNPLA3 harbors retinyl ester hydrolase activity and PNPLA3-I148M is associated with low serum retinol level, but enhanced retinyl esters in the liver of NAFLD patients. Low circulating retinol in NAFLD may therefore not reflect true “vitamin A deficiency”, but rather disturbed vitamin A metabolism. Here, we summarize current knowledge about vitamin A metabolism in NAFLD and its putative role in the progression of liver disease, as well as the therapeutic potential of vitamin A metabolites.

Biliopancreatic Diversion for Severe Obesity: Long-Term Effectiveness and Nutritional Complications

BACKGROUND

Bariatric surgery is currently the treatment of choice for those patients with severe obesity, but the procedure of choice is not clearly established. We describe weight loss and nutritional parameters in severely obese patients after biliopancreatic diversion for 10 years of follow-up.

METHODS

Patients were followed by the same multidisciplinary team, and data are shown for 10 years. Bariatric Analysis and Reporting Outcome System (BAROS) questionnaire, data regarding the evolution of obesity-related diseases, and nutritional parameters are reported.

RESULTS

Two hundred ninety-nine patients underwent biliopancreatic diversion, 76.1 % women, initial BMI 50.1 kg/m(2) (7.2). Weight loss was maintained throughout 10 years with EWL% around 65 % and EBMIL% around 70 %. More than 80 % of the patients showed EWL higher than 50 %. Blood pressure, glucose metabolism, and lipid profile clearly improved after surgery. Mean nutritional parameters remained within the normal range during follow-up. Protein malnutrition affected less than 4 % and anemia up to 16 %. Fat-soluble vitamin levels decreased along the time, with vitamin D deficiency in 61.5 % of patients. No significant differences were found either in nutritional parameters or weight loss regarding gastrectomy or gastric preservation, or common limb length longer or shorter than 55 cm

CONCLUSIONS

Biliopancreatic diversion is an effective surgical procedure in terms of weight loss, quality of life, and evolution of obesity-related diseases. Nutritional deficiencies are less frequent than feared for a malabsorptive procedure, but must be taken into account, especially for fat-soluble vitamins.

Recent advances in metabolic and bariatric surgery

Obesity and its associated medical conditions continue to increase and add significant burden to patients, as well as health-care systems, worldwide. Bariatric surgery is the most effective treatment for severe obesity and its comorbidities, and resolution of diabetes is weight loss-independent in the case of some operations. Although these weight-independent effects are frequently described clinically, the mechanisms behind them are not well understood and remain an intense area of focus in the growing field of metabolic and bariatric surgery. Perceptions of the mechanisms responsible for the beneficial metabolic effects of metabolic/bariatric operations have shifted from being mostly restrictive and malabsorption over the last 10 to 15 years to being more neuro-hormonal in origin. In this review, we describe recent basic and clinical findings of the major clinical procedures (adjustable gastric banding, vertical sleeve gastrectomy, Roux-en-Y gastric bypass, and biliopancreatic diversion) as well as other experimental procedures (ileal interposition and bile diversion) that recapitulate many of the metabolic effects of these complex operations in a simpler fashion. As the role of bile acids and the gut microbiome on metabolism is becoming increasingly well described, their potential roles in these improvements following metabolic surgery are becoming better appreciated. Bile acid and gut microbiome changes, in light of recent developments, are discussed in the context of these surgical procedures, as well as their implications for future study.

Hypovitaminosis D in bariatric surgery: A systematic review of observational studies

BACKGROUND

Obesity is a public health problem that carries global and substantial social and economic burden. Relative to non-surgical interventions, bariatric surgery has the most substantial and lasting impact on weight loss. However, it leads to a number of nutritional deficiencies requiring long term supplementation.

OBJECTIVES

The aims of this paper are to review 25-hydroxyvitamin D [25(OH)D] status pre and post bariatric surgery, describe the dose response of vitamin D supplementation, and assess the effect of the surgical procedure on 25(OH)D level following supplementation.

METHODS

We searched Medline, PubMed, the Cochrane Library and EMBASE, for relevant observational studies published in English, from 2000 to April 2015. The identified references were reviewed, in duplicate and independently, by two reviewers.

RESULTS

We identified 51 eligible observational studies assessing 25(OH)D status pre and/or post bariatric surgery. Mean pre-surgery 25(OH)D level was below 30ng/ml in 29 studies, and 17 of these studies showed mean 25(OH)D levels ≤20ng/ml. Mean 25(OH)D levels remained below 30ng/ml following bariatric surgery, despite various vitamin D replacement regimens, with only few exceptions. The increase in post-operative 25(OH)D levels tended to parallel increments in vitamin D supplementation dose but varied widely across studies. An increase in 25(OH)D level by 9-13ng/ml was achieved when vitamin D deficiency was corrected using vitamin D replacement doses of 1100-7100IU/day, in addition to the usual maintenance equivalent daily dose of 400-2000IU (total equivalent daily dose 1500-9100IU). There was no difference in mean 25(OH)D level following supplementation between malabsorptive/combination procedures and restrictive procedures.

CONCLUSION

Hypovitaminosisis D persists in obese patients undergoing bariatric surgery, despite various vitamin D supplementation regimens. Further research is needed to determine the optimal vitamin D dose to reach desirable 25(OH)D levels in this population, and to demonstrate whether this dose varies according to the surgical procedure.

Peripheral signals mediate the beneficial effects of gastric surgery in obesity

Obesity is nowadays a public health problem both in the industrialized world and developing countries. The different treatments to fight against obesity are not very successful with the exception of gastric surgery. The mechanism behind the achievement of this procedure remains unclear although the modifications in the pattern of gastrointestinal hormones production appear to be responsible for the beneficial effect. The gastrointestinal tract has emerged in the last time as an endocrine organ in charge of response to the different stimulus related to nutritional status by the modulation of more than 30 signals acting at central level to modulate food intake and body weight. The production of some of these gastric derived signals has been proved to be altered in obesity (ghrelin, CCK, and GLP-1). In fact, bariatric surgery modifies the production of both gastrointestinal and adipose tissue peripheral signals beyond the gut microbiota composition. Through this paper the main peripheral signals altered in obesity will be reviewed together with their modifications after bariatric surgery.

Revision and reversal after biliopancreatic diversion for excessive side effects or ineffective weight loss: a review of the current literature on indications and procedures

BACKGROUND

Biliopancreatic diversion is a powerful bariatric procedure that relies on gastric restriction combined with a large malabsorptive component. This can lead to excessive side effects and/or weight loss. Despite this, long-term weight regain can also occur.

OBJECTIVES

To determine the rate of and options for revision in patients who experience excessive side effects and weight loss. To explore the revisional procedures available to overcome weight regain.

METHODS

A PubMed search was conducted of all reports published between 1979 and August 31, 2014. Series and case reports on revision or reversal after biliopancreatic diversion with duodenal switch (BPD/DS) or without (BPD) were included.

RESULTS

Revision rates for excessive malabsorption ranges from .5%-4.9% and 3%-18.5% after BPD/DS and BPD respectively. Revisions increase common channel by up to 150 cm. Reversal is necessary in .2%-7% of cases, with an increased risk when the common channel is ≤ 50 cm. In most instances, reversal (of the malabsorptive component only) is indicated after the revision failure. A proximal, side-to-side anastomosis between the biliopancreatic and alimentary limbs is the preferred option. Most reoperations are performed within 2 years of the initial procedure and for protein malnutrition in about half of the cases. Revision for insufficient weight loss is reported in .5%-2.78% of cases. Except inadequate channel lengths, little is to be gained by common channel shortening. Additional gastric restriction, which results in an average 9-14 kg weight loss, is another option.

CONCLUSIONS

Biliopancreatic diversion can be relatively easily revised to control excessive side effects and protein malnutrition. Early diagnosis is essential and warrants a close nutritional monitoring. In case of weight regain, limited results can be obtained by reducing the gastric volume provided the lengths of the small bowel channels are adequate.

Metabolic surgery: action via hormonal milieu changes, changes in bile acids or gut microbiota? A summary of the literature

Obesity and type 2 diabetes remain epidemic problems. Different bariatric surgical techniques causes weight loss and diabetes remission to varying degrees. The underlying mechanisms of the beneficial effects of bariatric surgery are complex, and include changes in diet and behaviour, as well as changes in hormones, bile acid flow, and gut bacteria. We summarized the effects of multiple different bariatric procedures, and their resulting effects on several hormones (leptin, ghrelin, adiponectin, glucagon-like peptide 1 (GLP-1), peptide YY, and glucagon), bile acid changes in the gut and the serum, and resulting changes to the gut microbiome. As much as possible, we have tried to incorporate multiple studies to try to explain underlying mechanistic changes. What emerges from the data is a picture of clear differences between restrictive and metabolic procedures. The latter, in particular the roux-en-Y gastric bypass, induces large and distinctive changes in most measured fat and gut hormones, including early and sustained increase in GLP-1, possible through intestinal bile acid signalling. The changes in bile flow and the gut microbiome are causally inseparable so far, but new studies show that each contributes to the effects of weight loss and diabetes resolution.