Postoperative metabolic and nutritional complications of bariatric surgery

The role of dietitian follow-ups on nutritional outcomes post-bariatric surgery

BACKGROUND

Current evidence recommends dietary counselling with a registered dietitian (RD) for successful weight loss after metabolic bariatric surgery; however, there are limited data on the effect of RD follow-ups on micronutrient deficiencies. This study evaluated the effects of the number of postoperative RD visits on nutritional outcomes, including weight loss and micronutrient deficiencies.

OBJECTIVES

The aim of this study was to evaluate the effects of the number of postoperative registered dietitian visits on nutritional outcomes, including weight loss and micronutrient deficiencies after metabolic and bariatric surgery.

SETTING

Cleveland Clinic Abu Dhabi, United Arab Emirates METHODS: This retrospective study included patients who underwent bariatric surgery between September 2015 and June 2020. Demographics, weight loss, micronutrients, and the number of postoperative RD visits were evaluated. Baseline and 12-month postsurgery outcomes were compared based on the number of RD follow-ups.

RESULTS

A total of 174 primary and 46 revisions were included. Patients were 73.6% female, with a mean age of 40 years. The initial mean body mass index was 42.8 kg/m2. Number of RD visits were as follows: 0-1 (39 patients), 2 (59 patients), 3 (55 patients), and 4 or more (67 patients). Baseline (pre-operative) micronutrient values were within normal range. In comparison with the reference group (REF = 0-1 post-op RD visits), patients with 3 RD visits had 7% higher total body weight loss (P < .001) and maintained micronutrients within the normal range at 12 months postoperative. Mean differences in postoperative values were statistically significant (P < .05) for weight, vitamin B12, and vitamin D but not for hemoglobin, ferritin, calcium, folate, vitamin B1, copper, and zinc.

CONCLUSION

Our study suggests that three or more RD visits during the first 12 months after bariatric surgery are associated with improved outcomes, including significant percent total body weight loss and lower rates of micronutrient deficiencies.

Pre- and Post-surgical Prevalence of Thiamine Deficiency in Patients Undergoing Bariatric Surgery: a Systematic Review and Meta-analysis

Thiamine deficiency is a life-threatening nutritional abnormality observed in the patients with obesity and following bariatric surgery. The aim of the present study is to determine the prevalence of thiamine deficiency prior to and after bariatric procedures. PubMed, Web of Science, Google scholar, CENTRAL, ProQuest, and Scopus were searched to retrieve relevant studies containing data on thiamine deficiency in patients with obesity who underwent bariatric surgery. A proportional meta-analysis approach was used to pool the prevalence of thiamine deficiency prior and after surgery. Our comprehensive literature search retrieved 41 studies with relevant data. The pooled prevalence of thiamine deficiency was 7% (95% CI: 4-12%) at baseline. We observed that 19% (95% CI: 0-68%), 9% (95% CI: 3-17%), and 6% (95% CI: 3-9%) of patients had developed thiamine deficiency at 3 months, 6 months, and 1 year after surgery, respectively. We also report that the prevalence of thiamine deficiency in pregnant women who had history of bariatric surgery. The rate was highest in the first trimester (12%) compared to that in the second (8%) and third (10%) trimesters. The baseline prevalence is 7% for thiamine deficiency in bariatric surgery candidates. The prevalence rate of thiamin deficiency increased to 19% and 9% 3 and 6 months after surgery; however, the rate decreased to 6% 1 year after surgery. Due to the higher prevalence of thiamine deficiency in the early post-operative phase, close monitoring during this period is recommended. A similar strategy should be implemented for pregnant women with history of bariatric surgery in their first trimester.

Long-term effectiveness, outcomes and complications of bariatric surgery

Dietary imbalance and overeating can lead to an increasingly widespread disease - obesity. Aesthetic considerations aside, obesity is defined as an excess of adipose tissue that can lead to serious health problems and can predispose to a number of pathological changes and clinical diseases, including diabetes; hypertension; atherosclerosis; coronary artery disease and stroke; obstructive sleep apnea; depression; weight-related arthropathies and endometrial and breast cancer. A body weight 20% above ideal for age, gender and height is a severe health risk. Bariatric surgery is a set of surgical methods to treat morbid obesity when other treatments such as diet, increased physical activity, behavioral changes and drugs have failed. The two most common procedures currently used are sleeve gastrectomy and gastric bypass. This procedure has gained popularity recently and is generally considered safe and effective. Although current data show that perioperative mortality is low and better control of comorbidities and short-term complications is achieved, more randomized trials are needed to evaluate the long-term outcomes of bariatric procedures. This review aims to synthesize and summarize the growing evidence on the long-term effectiveness, outcomes and complications of bariatric surgery.

Which nutritional prognosis is better? comparison of the three most commonly performed bariatric surgeries: A systematic review and network meta-analysis

Background

Obesity is one of the most important public health conditions in the world, and surgical intervention is the only medical treatment recognized by the medical community as a complete and permanent cure for morbid obesity and its complications. The choice of surgical modality is also based more on the experience of the physician or the requirements of people with obesity, rather than on scientific data. In this issue, a thorough comparison of the nutritional deficiencies caused by the three most commonly used surgical modalities is needed.

Objectives

We aimed to use the network meta-analysis to compare the nutritional deficiencies caused by the three most common BS procedures in many subjects who underwent BS to help physicians determine the best BS surgical approach to apply to their clinical people with obesity.

Setting

A systematic review and network meta-analysis of world literature.

Methods

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, systematically reviewed the literature, and conducted a network meta-analysis using R Studio.

Results

For the four vitamins calcium, vitamin B12, iron and vitamin D, the micronutrient deficiency caused by RYGB is the most serious.

Conclusions

RYGB causes slightly higher nutritional deficiencies in Bariatric surgery, but RYGB remains the most commonly used modality for Bariatric surgery.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022351956, identifier: CRD42022351956.

Bariatric Surgery: Targeting pancreatic β cells to treat type II diabetes

Pancreatic β-cell function impairment and insulin resistance are central to the development of obesity-related type 2 diabetes mellitus (T2DM). Bariatric surgery (BS) is a practical treatment approach to treat morbid obesity and achieve lasting T2DM remission. Traditionally, sustained postoperative glycemic control was considered a direct result of decreased nutrient intake and weight loss. However, mounting evidence in recent years implicated a weight-independent mechanism that involves pancreatic islet reconstruction and improved β-cell function. In this article, we summarize the role of β-cell in the pathogenesis of T2DM, review recent research progress focusing on the impact of Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) on pancreatic β-cell pathophysiology, and finally discuss therapeutics that have the potential to assist in the treatment effect of surgery and prevent T2D relapse.

The relationship between preoperative weight loss and intra and post-bariatric surgery complications: an appraisal of the current preoperative nutritional strategies

Preoperative weight loss before a bariatric surgery reduces long-term complications, but there is no solid evidence for short-term or perioperative complications. This review highlights recent evidence on dietary protocols and the possible correlation between weight loss and surgical complications. Updated evidence was searched in PubMedDirect with the terms "preoperative very low-calorie diet or very-low-calorie ketogenic diet or low-fat diet or intermittent fasting or Mediterranean diet and bariatric surgery or bariatric surgery complications." The main characteristics of each diet, achievements related to weight loss, liver reduction, peri and postoperative outcomes, surgical complications, tolerance, and adherence to the diet are presented from the selected studies. There are few reports about the Mediterranean diet as a strategy to reach these goals. The VLCKD has been associated with better body weight reduction and lesser postoperative complications risk. However, the results in animal models are still controversial. When comparing VLCD with an LCD, there is no apparent superiority between one against the other one. However, LCD has shown better tolerance and adherence than VLCD. There is still a need for more controlled studies to define the best preoperative dietary treatment for weight loss before bariatric surgery since there are controversial positions regarding this issue.

The Impact of Pregnancy on Outcomes After Bariatric Surgery

BACKGROUND

Bariatric surgery is performed mostly on obese women of reproductive age. Many studies have analyzed pregnancy outcomes after bariatric surgery, but only a small number have studied the impact of pregnancy on the postoperative outcomes.

PURPOSE

To study the effect of pregnancy on outcomes after bariatric surgery in women of childbearing age.

METHODS

From January 2010 to October 2017, a retrospective study of a prospectively maintained database was conducted at the University Hospital of Geneva (HUG), where 287 women between the ages of 18 and 45 years had undergone Roux-en-Y gastric bypass (RYGB). A comparison of the results during a 5-year follow-up was performed between women who became pregnant after their bariatric surgery (pregnancy group, n = 40) and postoperative non-pregnant women (non-pregnancy group, n = 247). The two groups were compared for weight loss, complications, and nutritional deficiencies.

RESULTS

The pregnancy group was significantly younger (29.2 ± 5.5 vs. 36.4± 6.3 years, p < 0.001) and heavier (124.0 ± 18.0 kg vs. 114.7 ± 17.1, p < 0.001) compared with the non-pregnancy group at the time of surgery. The percentage of excess BMI loss (%EBMI loss) was similar in both groups during the 5-year follow-up. Complications after RYGB and nutritional deficiencies were nearly identical in the two groups. The interval of time between bariatric surgery and first pregnancy was a median of 20.8 months. Out of 40 first pregnancies, 28 women completed pregnancy successfully with live birth.

CONCLUSION

Pregnancy after bariatric surgery is safe and does not adversely affect outcomes after RYGB.

Prevalence of Low Plasma Vitamin B1 in the Stroke Population Admitted to Acute Inpatient Rehabilitation

OBJECTIVE

To determine the prevalence of vitamin B1 (VitB1) deficiency in the stroke population admitted to acute inpatient rehabilitation.

DESIGN

Retrospective cohort study.

SETTING

Acute inpatient rehabilitation facility at an academic medical center.

PARTICIPANTS

119 consecutive stroke patients admitted to stroke service from 1 January 2018 to 31 December 2018.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Plasma VitB1 level.

RESULTS

There were 17 patients (14%; 95% CI 9-22%) with low VitB1 with a range of 2-3 nmol/L, an additional 58 (49%; CI 40-58%) patients had normal low VitB1 with a range of 4-9 nmol/L, twenty-five patients (21%; CI 15-29%) had normal high VitB1 with a range of 10-15 nmol/L, and nineteen patients (16%; CI 10-24%) had high VitB1 with a range of 16-43 nmol/L.

CONCLUSIONS

In this cohort of patients admitted to the stroke service at an acute rehabilitation facility, there is evidence of thiamine deficiency. Moreover, the data suggest that there is inadequate acute intake of VitB1. Given the role of thiamine deficiency in neurologic function, further study of the role of thiamine optimization in the acute stroke rehabilitation population is warranted.

Bariatric Surgery in Obesity: Effects on Gut Microbiota and Micronutrient Status

Obesity is associated with reduced gut microbial diversity and a high rate of micronutrient deficiency. Bariatric surgery, the therapy of choice for severe obesity, produces sustained weight loss and improvements in obesity-related comorbidities. Also, it significantly alters the gut microbiota (GM) composition and function, which might have an important impact on the micronutrient status as GM is able to synthesize certain vitamins, such as riboflavin, folate, B12, or vitamin K2. However, recent data have reported that GM is not fully restored after bariatric surgery; therefore, manipulation of GM through probiotics represents a promising therapeutic approach in bariatric patients. In this review, we discuss the latest evidence concerning the relationship between obesity, GM and micronutrients, the impact of bariatric surgery on GM in relation with micronutrients equilibrium, and the importance of the probiotics' supplementation in obese patients submitted to surgical treatment.

Malnutrition in obesity before and after bariatric surgery

Bariatric surgeries are considered the only effective way of weight loss therapy in morbidly obese patients, i.e. body mass index ≥ 35. However, micronutrient deficiencies and malnutrition are common after most bariatric procedures and thus, pre- and postoperative nutritional assessment and corrections are advised. The present review is presented in an effort to describe in some detail about prevalence, and mechanisms of macro- and micronutrient deficiencies in obese and post-bariatric surgery individuals. We also aimed to summarize the data on screening and supplementation of macro- and micronutrients before and after bariatric surgeries.

Vitamin K-what is known regarding bariatric surgery patients: a systematic review

Vitamin K, a fat-soluble vitamin, is involved in blood coagulation, bone mineralization, inhibition of vascular calcification, and regulation of numerous enzyme systems. Patients who undergo bariatric surgery (BS), especially procedures that involve a malabsorptive component, are prone to develop vitamin K deficiency (VKD). The causes of VKD include decreased absorptive surface areas, steatorrhea, bacterial overgrowth, marked reduction of carriers of vitamin K, decrease in vitamin K intake, and modifications of gut microbiota. Data on vitamin K status among BS patients are scarce and the strength of evidence supporting vitamin K supplementation is weak. Thus, this systematic review summarized the scientific literature on vitamin K and examined the status among patients before and after BS, as well as among pregnant women with a history of BS. A MEDLINE/Pubmed and Embase electronic search was performed. After a thorough screening of 204 titles, 19 articles were selected by 2 independent reviewers. Five studies on BS candidates (n = 750), 12 studies after BS (n = 1442), and 4 studies on pregnant woman after BS (n = 83, of them n = 7 from case reports) were included. Results of the current review suggest that patients who undergo major malabsorptive surgeries are at a higher risk of developing VKD and should be better monitored. At this point, it is still unclear whether supplementation of vitamin K is required, and what oral dose or vitamer type should be used to normalize serum levels after different types of bariatric procedures. It should be noted that the current protocols for VKD treatment are still experiential in these patients. It is also unknown at what intervals screening tests for vitamin K should be performed and what assay is most appropriate for screening purposes. Future studies are needed to answer these unresolved issues.

Obesity and hypovitaminosis D: causality or casualty?

Epidemiological studies reported that vitamin D deficiency represents an increasingly widespread phenomenon in various populations. Vitamin D deficiency is considered a clinical syndrome determined by low circulating levels of 25-hydroxyvitamin D (25(OH)D), which is the biologically-inactive intermediate and represents the predominant circulating form. Different mechanisms have been hypothesized to explain the association between hypovitaminosis D and obesity, including lower dietary intake of vitamin D, lesser skin exposure to sunlight, due to less outdoor physical activity, decreased intestinal absorption, impaired hydroxylation in adipose tissue and 25(OH)D accumulation in fat. However, several studies speculated that vitamin D deficiency itself could cause obesity or prevent weight loss. The fat-solubility of vitamin D leads to the hypothesis that a sequestration process occurs in body fat depots, resulting in a lower bioavailability in the obese state. After investigating the clinical aspects of vitamin D deficiency and the proposed mechanisms for low 25(OH)D in obesity, in this manuscript we discuss the possible role of vitamin D replacement treatment, with different formulations, to restore normal levels in individuals affected by obesity, and evaluate potential positive effects on obesity itself and its metabolic consequences. Food-based prevention strategies for enhancement of vitamin D status and, therefore, lowering skeletal and extra-skeletal diseases risk have been widely proposed in the past decades; however pharmacological supplementation, namely cholecalciferol and calcifediol, is required in the treatment of vitamin D insufficiency and its comorbidities. In individuals affected by obesity, high doses of vitamin D are required to normalize serum vitamin D levels, but the different liposolubility of different supplements should be taken into account. Although the results are inconsistent, some studies reported that vitamin D supplementation may have some beneficial effects in people with obesity.

Warfarin Dose Adjustment After Biliopancreatic Diversion/Duodenal Switch Bariatric Surgery

BACKGROUND

The absorption of drugs and fat-soluble vitamins is impaired after bariatric surgery on which intestinal length and function are altered. In this context, the anticoagulant effect of warfarin is difficult to predict in the postoperative period.

OBJECTIVE

This study aimed at describing the average weekly warfarin dose required to maintain a therapeutic international normalized ratio (INR) before and up to 1 year after sleeve gastrectomy with biliopancreatic diversion and duodenal switch (BPD/DS). Secondary end points included the number of patients requiring a minimal 20% reduction in their weekly dose of warfarin following the BPD/DS.

METHODS

This descriptive and retrospective longitudinal population study included 20 patients using warfarin who underwent BPD/DS. An INR was considered nontherapeutic if it was below or above 15% of the targeted therapeutic range for any given patient.

RESULTS

One month after the surgery, the median weekly dose of warfarin was 55% lower than the preoperative dose ( P < 0.0001). In the 9 patients with full follow-up data, the warfarin dose at 1 year was still 39% lower than the preoperative dose ( P < 0.05). At that time, all patients presented a minimal dose reduction of 20%.

CONCLUSIONS

BPD/DS robustly reduced the requirement of warfarin, which resulted in lower doses after surgery. This persisted over the first year after the surgery, likely because of enhanced sensitivity. The mechanisms for this effect remain multifactorial, and the exact extent of change in dose cannot be predicted.

Vitamin D alteration associated with obesity and bariatric surgery

Obesity and severe obesity constitute growing serious health problems reaching epidemic proportion in most countries. Interactions and relationships between obesity and bone tissue and its metabolism are complex but are more and more studied and recognized. Obesity is associated with an altered hormonal profile including particularly bone-regulating hormones like vitamin D. Bariatric surgery procedures, thanks to their effectiveness to achieve therapeutic endpoints for comorbidities associated with obesity, have had an increasing success. However, these surgeries by producing mechanical restriction and or malabsorption syndrome lead to nutritional deficiencies including vitamin D. In this review, we aim to (1) discuss the nutritional deficiency of vitamin D in the obese, (2) to summarize the different surgical options in bariatric surgery and to present the evidence concerning these procedures and their associated profile in vitamin D post-operative insufficiency, (3) to present the different recommendations in clinical practice to prevent or treat vitamin D deficiencies or insufficiencies in patients treated by bariatric surgery and finally to introduce emerging assumptions on the relationship between vitamin D, microbiota composition and circulating bile acids. Impact statement Obesity and severe obesity constitute growing serious health problems reaching epidemic proportion in most countries with a prevalence increasing from 6.4 in 1975 to 14.9% in 2014. This present review summarizes currently available data on vitamin D deficiencies in the obese population before and after bariatric surgery. The important evidence emerging from our evaluation confirms that obese patients are at risk of multiple nutritional deficiencies, especially vitamin D deficiency, before bariatric surgery. Our survey confirms that the precise role of the gut microbiome and its associated changes on the vitamin D metabolism after the different bariatric surgery procedures has not yet been studied. Furthermore, whether differences in the microbiota may alter the therapeutic responses to vitamin D is not known.

The Surgical Management of Obesity

In the United States, more than one-third of the population is obese. Currently, bariatric surgery is the best known treatment for obesity, and multiple meta-analyses have shown bariatric surgery to be more effective for treating obesity than diet and exercise or pharmacologic treatment. The modern era of bariatric surgery began in 2005, which is defined by a drastic increase in the use of laparoscopy. Bariatric surgery has the potential to improve obesity-related comorbidities, such as type 2 diabetes, cardiovascular disease, and sleep apnea. The effect of bariatric surgery on weight loss and comorbidities varies by the type of procedure.

Type 2 Diabetes Mellitus remission eighteen months after Roux-en-Y gastric bypass

OBJECTIVE

to evaluate the effectiveness of Roux-en-Y gastric bypass in improving the glycemic profile of obese patients with type 2 Diabetes Mellitus (DM2) after 18 months of follow-up.

METHODS

four hundred sixty-eight pacients with DM2 and BMI ≥35 were submitted to Roux-en-Y gastric bypass, from 1998 to 2010. All patients were submitted to glycemic control analysis in the 3rd, 6th, 9th, 12th and 18th postoperative months. We considered: type 2 diabetic patients, the ones with fasting glucose ≥126mg/dl and HbA1C ≥6.5 in two dosages; high risk patients for diabetes, those who presented fasting glucose ≥ 100 to 125 mg/dl and HbA1C between 5.7%-6.4%; and normal patients, those presenting glucose <100mg/dl and HbA1C <5.7%. Such diagnostic criteria were based on the official position of Sociedade Brasileira de Diabetes, published in July, 2011.

RESULTS

The remission of DM2 was seen in 410 (87.6%) out of 468 patients 18 months after the surgery, that being a meaningful difference, with p<0.001. Fourty-eight (10.3%) patients sustained criteria for the disease and ten (2.1%) continued at high risk for DM2.

CONCLUSIONS

Roux-en-Y gastric bypass was effective in the promotion and maintaince of long-term glycemic control. There are evidences showing that the remission of DM2 is not only related to weight loss and that other enteroinsular axis mechanisms must be involved.

OBJETIVO

avaliar a eficácia da gastroplastia com derivação em Y-de-Roux, em pacientes obesos e portadores de Diabetes Mellitus tipo 2 (DM2), na melhoria do perfil glicêmico após 18 meses de seguimento.

MÉTODOS

foram submetidos à derivação gástrica em Y-de-Roux 468 pacientes com IMC ≥35 e portadores de DM2, no período de 1998 a 2010. Todos os pacientes tiveram a análise do controle glicêmico realizadas no terceiro, sexto, nono, 12o e 18o meses de pós-operatório. Os critérios diagnósticos de diabetes foram baseados no Posicionamento Oficial da Sociedade Brasileira de Diabetes, publicado em julho de 2011.

RESULTADOS

observou-se a remissão do DM2 em 410 pacientes (87,6%) após 18 meses da cirurgia, sendo essa diferença significativa com p-valor <0,001. A doença se manteve inalterada em 48 pacientes (10,3%), e dez pacientes (2,1%) permaneceram com o risco aumentado para DM2.

CONCLUSÃO

a gastroplastia com derivação em Y-de-Roux foi efetiva na promoção e manutenção do controle glicêmico em longo prazo.

Bacterial Lipopolysaccharide, Lipopolysaccharide-Binding Protein, and Other Inflammatory Markers in Obesity and After Bariatric Surgery

Obesity is associated with altered gut microbiota and low-grade inflammation. A key factor in the inflammatory process is endotoxin lipopolysaccharide (LPS). Plasma LPS levels and sensory agent lipopolysaccharide-binding protein (LBP) are shown to be elevated in obesity. This elevation may be due to increased intestinal permeability and incorporation of a high-fat diet accompanied by overfeeding. Bariatric surgery has become a popular treatment option that results in stable weight loss and improvement of obesity-related conditions. Studies outlined in this review show reduced LPS and LBP levels after different bariatric procedures. LPS receptor CD14 and mRNA expression toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4) were also shown to have reduced levels following surgery. Changes in LPS and LPS components after bariatric surgery are shown to be linked to the surgical technique of the procedure and restriction of caloric intake. Additionally, changes in the gut microbiota provide some insight to the reduction of inflammatory markers after surgery. The beneficial effects of bariatric surgery are not dependent on weight loss alone. The inflammatory pathway plays a key role in the improvement of metabolic complications following surgery that should be further examined. Additional research is needed to evaluate short- and long-term changes of LPS and LPS components after bariatric surgery, including how those assessments can be applied to clinical practice.

[Total hip arthroplasty in overweight osteoarthritis patients]

BACKGROUND

An increasing number of patients scheduled for total hip arthroplasty (THA) are obese and exhibit a different risk profile from that of patients of normal weight.

OBJECTIVES

To provide an overview of the impact of obesity on the outcome of primary THA.

MATERIALS AND METHODS

Literature review and discussion of own epidemiological data.

RESULTS

Obese patients can expect as much functional improvement as non-obese patients after THA. However, peri- and postoperative complication (e.g., periprosthetic infection and dislocation) rates are reported to be increased in obese THA patients.

CONCLUSIONS

The knowledge of obesity-associated risks is the prerequiste for successful THA in obese patients.

Advances in clinical determinants and neurological manifestations of B vitamin deficiency in adults

B vitamin deficiency is a leading cause of neurological impairment and disability throughout the world. Multiple B vitamin deficiencies often coexist, and thus an understanding of the complex relationships between the different biochemical pathways regulated in the brain by these vitamins may facilitate prompter diagnosis and improved treatment. Particular populations at risk for multiple B vitamin deficiencies include the elderly, people with alcoholism, patients with heart failure, patients with recent obesity surgery, and vegetarians/vegans. Recently, new clinical settings that predispose individuals to B vitamin deficiency have been highlighted. Moreover, other data indicate a possible pathogenetic role of subclinical chronic B vitamin deficiency in neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. In light of these findings, this review examines the clinical manifestations of B vitamin deficiency and the effect of B vitamin deficiency on the adult nervous system. The interrelationships of multiple B vitamin deficiencies are emphasized, along with the clinical phenotypes related to B vitamin deficiencies. Recent advances in the clinical determinants and diagnostic clues of B vitamin deficiency, as well as the suggested therapies for B vitamin disorders, are described.

Effect of vitamin D supplementation alone or with calcium on adiposity measures: a systematic review and meta-analysis of randomized controlled trials

CONTEXT

The independent or interactive effects of vitamin D and calcium on adiposity remain inconclusive.

OBJECTIVE

The objective of this systematic review and meta-analysis was to assess whether vitamin D and calcium supplements cause changes in adiposity.

DATA SOURCES

MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials databases were searched for literature published from 1966 to March 2014.

STUDY SELECTION

A systematic search was conducted for randomized clinical trials with ≥ 50 participants aged ≥ 18 years at baseline who had received at least 12 weeks of treatment. Among the inclusion criteria were supplementation with vitamin D with or without calcium and measurement of adiposity (weight, body mass index [BMI], and/or fat mass).

DATA EXTRACTION

The primary endpoints assessed were changes in weight, BMI, or fat mass.

DATA SYNTHESIS

Of 953 trials identified, 26 randomized clinical trials (n = 12, vitamin D alone; n = 10, vitamin D plus calcium versus calcium control; n = 4, vitamin D plus calcium versus placebo) with a total of 42,430 participants (median duration, 12 months) met the inclusion criteria. When compared with placebo, vitamin D supplementation had no significant effect on BMI (weighted mean difference [WMD], -0.06 kg/m(2); 95% confidence interval [95%CI], -0.14 to 0.03), weight (WMD, -0.05 kg; 95%CI, -0.32 to 0.23), or fat mass (WMD, -0.43 kg; 95%CI, -1.69 to 0.84). Likewise, no significant reduction in BMI (WMD, 0.02 kg/m(2); 95%CI, -0.11 to 0.14), weight (WMD, 0.12 kg; 95%CI, -0.24 to 0.49), or fat mass (WMD, 0.12 kg; 95%CI, -0.22 to 0.45) was observed in participants who received vitamin D plus calcium compared with those who received calcium control.

CONCLUSIONS

Supplementation with vitamin D showed no effect on adiposity measures in adults.

Thiamin deficiency in people with obesity

Although obesity has been viewed traditionally as a disease of excess nutrition, evidence suggests that it may also be a disease of malnutrition. Specifically, thiamin deficiency was found in 15.5-29% of obese patients seeking bariatric surgery. It can present with vague signs and symptoms and is often overlooked in patients without alcohol use disorders. This review explores the relatively new discovery of high rates of thiamin deficiency in certain populations of people with obesity, including the effects of thiamin deficiency and potential underlying mechanisms of deficiency in people with obesity. The 2 observational studies that examined the prevalence in preoperative bariatric surgery patients and gaps in our current knowledge (including the prevalence of thiamin deficiency in the general obese population and whether the current RDA for thiamin meets the metabolic needs of overweight or obese adults) are reviewed. Suggestions for future areas of research are included.

Skin changes after bariatric surgery

Today, obesity is considered an epidemic all over the world and it is recognized as one of the major public health problems. Bariatric surgery is considered an appropriate therapeutic option for obesity with progressively increasing demands. The changes resulting from massive weight loss after bariatric surgery are related to numerous complications. This article will present the dermatological alterations that can be found after bariatric surgery. They will be subdivided into dermatoses that are secondary to metabolic and nutritional disorders, those derived from cutaneous structural modifications after major weight loss and the influence the latter may have in improving of certain dermatoses.

Review article: The nutritional and pharmacological consequences of obesity surgery

BACKGROUND

Obesity surgery is acknowledged as a highly effective therapy for morbidly obese patients. Beneficial short-term effects on common comorbidities are practically undisputed, but a growing data pool from long-term follow-up reveals increasing evidence of potentially severe nutritional and pharmacological consequences.

AIMS

To assess the prevalence, causes and symptoms of complications after obesity surgery, to elucidate and compare therapy recommendations for macro- and micronutrient deficiencies, and to explore surgically-induced effects on drug absorption and bioavailability, discussing ramifications for long-term therapy and prophylaxis.

METHODS

PubMed, Embase and MEDLINE were searched using terms including, but not limited to, bariatric surgery, gastric bypass, obesity surgery and Roux-en-Y, coupled with secondary search terms, e.g. anaemia, micronutrients, vitamin deficiency, bacterial overgrowth, drug absorption, pharmacokinetics, undernutrition. All studies in English, French or German published January 1980 through March 2014 were included.

RESULTS

Macro- and micronutrient deficiencies are common after obesity surgery. The most critical, depending on surgical technique, are hypoalbuminemia (3-18%) and deficiencies of vitamins B1 (≤49%), B12 (19-35%) and D (25-73%), iron (17-45%) and zinc (12-91%). Many drugs commonly administered to obese patients (e.g. anti-depressants, anti-microbials, metformin) are subject to post-operative and/or PPI-associated changes affecting bioavailability and absorption.

CONCLUSIONS

Complications are associated with pre-operative and/or post-operative malnutrition or procedure-related changes in intake, absorption and drug bioavailability. The high prevalence of nutrient deficiencies after obesity surgery makes life-long nutritional monitoring and supplementation essential. Post-operative changes to drug absorption and bioavailability in bariatric patients cast doubt on the validity of standard drug dosage and administration recommendations.

Pharmacotherapy prevention and management of nutritional deficiencies post Roux-en-Y gastric bypass

Roux-en-Y gastric bypass is the most commonly performed bariatric procedure. It is associated with nutritional deficiencies due to gastric reduction, intestinal bypass, reduced caloric intake, avoidance of nutrient-rich foods, noncompliance with supplementation and poor food tolerability. Although there are multiple publications on this topic, there is a lack of consistent guidance for the healthcare practitioner caring for the bariatric patient. This article will encompass literature reviewing the pharmacotherapy approach to prevention and management of nutritional deficiencies since the American Society of Metabolic and Bariatric Surgery guidelines were published in 2008.

Dermatological complications after bariatric surgery: report of two cases and review of the literature

Bariatric surgery aims at weight reduction of severely obese patients. The Roux-en-Y technique is one of the most common bariatric procedures and is occasionally accompanied by nutrient insufficiencies and metabolic changes. According to the literature, skin architecture and immunity change after bariatric surgery and may lead to inflammation and increased susceptibility to pathogens. Additionally, vitamin and mineral deficiencies frequently develop in these patients and affect the skin's defense mechanisms, possibly contributing to dermatological complications. Knowledge and recognition of skin changes after bariatric surgery make an important asset for the dermatologist and help in the proper treatment of these patients. We report 2 cases of infectious skin lesions where vitamin and trace element deficiencies have possibly contributed to their persistence and resistance to traditional treatments.

Bariatric emergencies: current evidence and strategies of management

BACKGROUND

The demand for bariatric surgery is increasing and the postoperative complications are seen more frequently. The aim of this paper is to review the current outcomes of bariatric surgery emergencies and to formulate a pathway of safe management.

METHODS

The PubMed and Google search for English literatures relevant to emergencies of bariatric surgery was made, 6358 articles were found and 90 papers were selected based on relevance, power of the study, recent papers and laparoscopic workload. The pooled data was collected from these articles that were addressing the complications and emergency treatment of bariatric patients. 830,998 patients were included in this review.

RESULTS

Bariatric emergencies were increasingly seen in the Accident and Emergency departments, the serious outcomes were reported following complex operations like gastric bypass but also after gastric band and the causes were technical errors, suboptimal evaluation, failure of effective communication with bariatric teams who performed the initial operation, patients factors, and delay in the presentation. The mortality ranged from 0.14%-2.2% and increased for revisional surgery to 6.5% (p = 0.002). Inspite of this, mortality following bariatric surgery is still less than that of control group of obese patients (p = value 0.01).

CONCLUSIONS

Most mortality and catastrophic outcomes following bariatric surgery are preventable. The awareness of bariatric emergencies and its effective management are the gold standards for best outcomes. An algorithm is suggested and needs further evaluation.

Gastrointestinal changes after bariatric surgery

Severe obesity is a preeminent health care problem that impacts overall health and survival. The most effective treatment for severe obesity is bariatric surgery, an intervention that not only maintains long-term weight loss but also is associated with improvement or remission of several comorbidies including type 2 diabetes mellitus. Some weight loss surgeries modify the gastrointestinal anatomy and physiology, including the secretions and actions of gut peptides. This review describes how bariatric surgery alters the patterns of gastrointestinal motility, nutrient digestion and absorption, gut peptide release, bile acids and the gut microflora, and how these changes alter energy homeostasis and glucose metabolism.

The effect of bariatric surgery on psychiatric course among patients with bipolar disorder

OBJECTIVE

Bariatric surgery is the most effective therapy for severe obesity. People with bipolar disorder have increased risk of obesity, yet are sometimes considered ineligible for bariatric surgery due to their bipolar disorder diagnosis. This study aimed to determine if bariatric surgery alters psychiatric course among stable patients with bipolar disorder.

METHODS

A matched cohort study (2006-2009) with mean follow-up of 2.17 years was conducted within Kaiser Permanente Northern California, a group practice integrated health services delivery organization that provides medical and psychiatric care to 3.3 million people. Participants were 144 severely obese patients with bipolar disorder who underwent bariatric surgery, and 1,440 control patients with bipolar disorder, matched for gender, medical center, and contemporaneous health plan membership. Controls met referral criteria for bariatric surgery. Hazard ratio for psychiatric hospitalization, and change in rate of outpatient psychiatric utilization from baseline to Years 1 and 2, were compared between groups.

RESULTS

A total of 13 bariatric surgery patients (9.0%) and 153 unexposed to surgery (10.6%) had psychiatric hospitalization during follow-up. In multivariate Cox models adjusting for potential confounding factors, the hazard ratio of psychiatric hospitalization associated with bariatric surgery was 1.03 [95% confidence interval (CI): 0.83-1.23]. In fully saturated multivariate general linear models, change in outpatient psychiatric utilization was not significantly different for surgery patients versus controls, from baseline to Year 1 (-0.4 visits/year, 95% CI: -0.5 to 0.4) or baseline to Year 2 (0.4 visits/year, 95% CI: -0.1 to 1.0).

CONCLUSIONS

Bariatric surgery did not affect psychiatric course among stable patients with bipolar disorder. The results of this study suggest that patients with bipolar disorder who have been evaluated as stable can be considered for bariatric surgery.

Laboratory testing for and diagnosis of nutritional deficiencies in pregnancy before and after bariatric surgery

OBJECTIVE

Bariatric surgery can reduce the risk of obesity-related complications of pregnancy, but may cause essential nutrient deficiencies. To assess adherence to laboratory testing guidelines, we examined frequency of testing for and diagnosis of deficiency during preconception and pregnancy using claims data in women with a delivery and bariatric surgery.

METHODS

Retrospective analysis of claims from seven Blue Cross/Blue Shield plans between 2002 and 2008. We included women with a delivery and bariatric surgery within the study period. We used common procedural terminology (CPT) and ICD-9 codes to define laboratory testing and deficiencies for iron, folate, vitamin B12, vitamin D, and thiamine. Using Student's t-test and chi-square testing, we compared frequency of laboratory tests and diagnoses during 12 months preconception and 280 days of pregnancy between women with pregnancy before versus after surgery. We used multivariate logistic regression to evaluate for predictors of laboratory testing.

RESULTS

We identified 456 women with pregnancy after bariatric surgery and 338 before surgery. The frequency of testing for any deficiency was low (9%-51%), but higher in those with pregnancy after surgery (p<0.003). The most common deficiency was vitamin B12 (12%-13%) with pregnancy after surgery (p<0.006). Anemia and number of health provider visits were independent predictors of laboratory testing.

CONCLUSION

Women with pregnancy after bariatric surgery were tested for and diagnosed with micronutrient deficiencies more frequently than those with pregnancy before surgery. However, most laboratory testing occurred in less than half the women and was triggered by anemia. Increased testing may help identify nutrient deficiencies and prevent consequences for maternal and child health.

Vitamin B12 deficiency in patients undergoing bariatric surgery: preventive strategies and key recommendations

BACKGROUND

Advances in bariatric surgery have brought about a paradigm shift in the management of obesity, with benefits extending beyond weight loss. However, nutritional deficiencies are an inherent problem in the postoperative period and often require lifelong supplementation. Vitamin B12, also referred to as cobalamin, is one of the most common micronutrient deficiencies affecting this population. This review explores the pathophysiology of cobalamin deficiency in patients undergoing bariatric surgery and provides an overview of the effectiveness of various available vitamin B12 formulations.

METHODS

To identify the relevant literature, a systematic review of MEDLINE was conducted from the earliest dates through September 2012 for English-language articles describing the prevention and management of vitamin B12 deficiency in patients undergoing bariatric surgery.

RESULTS

Intramuscular vitamin B12 continues to be the gold standard of therapy for vitamin B12 deficiency, especially in symptomatic patients. In select patients with asymptomatic vitamin B12 deficiency after Roux-en-Y gastric bypass (RYGB), high-dose oral cyanocobalamin should be given a consideration, especially when there are concerns with the adherence to intramuscular therapy or if compliance comes into question. Unlike patients post-RYGB, those undergoing restrictive procedures such as gastric banding and sleeve gastrectomy may be maintained postoperatively on a lower-dose daily vitamin B12 supplementation. Efficacy data of nasal and sublingual routes for maintenance therapy is currently awaited.

CONCLUSION

Patients undergoing bariatric surgery must be continuously educated on proper nutrition, the risk of developing significant vitamin B12 deficiency, and the role of supplements in avoiding catastrophic consequences.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, the Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, the Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Quick fix or long-term cure? Pros and cons of bariatric surgery

The past decade has seen an enormous increase in the number of bariatric, or weight loss, operations performed. This trend is likely to continue, mirroring the epidemic of obesity around the world and its rising prevalence among children. Bariatric surgery is considered by many to be the most effective treatment for obesity in terms of maintenance of long-term weight loss and improvement in obesity-related comorbid conditions. Although overly simplified, the primary mechanisms of the surgical interventions currently utilized to treat obesity are the creation of a restrictive or malabsorptive bowel anatomy. Operations based on these mechanisms include the laparoscopic adjustable gastric band and laparoscopic vertical sleeve gastrectomy (considered primarily restrictive operations), the laparoscopic biliopancreatic diversion with or without a duodenal switch (primarily malabsorptive operation), and the laparoscopic Roux-en-Y gastric bypass (considered a combination restrictive and selective malabsorptive procedure). Each operation has pros and cons. Important considerations, for the patient and surgeon alike, in the decision to proceed with bariatric surgery include the technical aspects of the operation, postoperative complications including long-term nutritional problems, magnitude of initial and sustained weight loss desired, and correction of obesity-related comorbidities. Herein, the pros and cons of the contemporary laparoscopic bariatric operations are reviewed and ongoing controversies relating to bariatric surgery are discussed: appropriate patient selection, appropriate operation selection for an individual patient, surgeon selection, and how to measure success after surgery.

Overview of bariatric surgery for the physician

The worldwide pandemic of obesity carries alarming health and socioeconomic implications. Bariatric surgery is currently the only effective treatment for severe obesity. It is safe, with mortality comparable to that of cholecystectomy, and effective in producing substantial and sustainable weight loss, along with high rates of resolution of associated comorbidities, including type 2 diabetes. For this reason, indications for bariatric surgery are being widened. In addition to volume restriction and malabsorption, bariatric surgery brings about neurohormonal changes that affect satiety and glucose homeostasis. Increased understanding of these mechanisms will help realise therapeutic benefits by pharmacological means. Bariatric surgery improves long-term mortality but can cause long-term nutritional deficiencies. The safety of pregnancy after bariatric surgery is still being elucidated.

Total knee arthroplasty in morbidly obese patients treated with bariatric surgery: a comparative study

Our objective was to compare outcomes (anesthesia time, total operative time, tourniquet time, duration of hospital stay, 90-day complication rate, and transfusion rates) of patients with total knee arthroplasty (TKA) who underwent bariatric surgery before or after TKA. One hundred twenty-five patients were included: TKA before bariatric surgery (group 1; n = 39), TKA within 2 years of bariatric surgery (group 2; n = 25), and TKA more than 2 years after bariatric surgery (group 3; n = 61). Patients with TKA more than 2 years after bariatric surgery had shorter anesthesia and total operative and tourniquet times than other groups; differences were significant between groups. Ninety-day complication and transfusion rates approached but did not meet statistical significance. Ninety-day complication rates and duration of hospital stay did not differ significantly between the 3 groups. The level of evidence was level II (cohort study).

Update on micronutrients in bariatric surgery

PURPOSE OF REVIEW

Obesity is a growing worldwide epidemic. Obese patients are often deficient in micronutrients despite macronutrient excess. Bariatric surgery is an increasingly utilized modality in the treatment of obesity and obesity-related conditions. Bariatric surgery itself may cause or exacerbate micronutrient deficiencies with serious sequelae. This review will focus on perioperative strategies to detect, prevent and treat micronutrient deficiencies in patients undergoing bariatric surgery, and will highlight practical and clinical aspects of these nutritional problems.

RECENT FINDINGS

Micronutrient deficiency is common in obese patients undergoing bariatric surgery both preoperatively and postoperatively. Bariatric procedures with a malabsorptive component are more likely to result in postoperative micronutrient deficiency. A system-based approach will facilitate clinical suspicion of specific or combined micronutrient deficiencies, leading to appropriate laboratory tests for confirmation. Supplementation by the oral route is always tried first, reserving parenteral administration for specific situations.

SUMMARY

Clinicians should be aware that micronutrient deficiencies are common in obese patients who may have macronutrient excess. Micronutrient deficiency may exist preoperatively or be caused by bariatric procedures themselves. A systematic and team-based approach will decrease morbidity associated with delays in diagnosis and treatment.

Assessment of different bariatric surgeries in the treatment of obesity and insulin resistance in mice

OBJECTIVE

To assess the effects of different bariatric surgical procedures on the treatment of obesity and insulin resistance in high fat diet-induced obese (DIO) mice.

BACKGROUND

Bariatric surgery is currently considered the most effective treatment for morbid obesity and its comorbidities; however, a systematic study of their mechanisms is still lacking.

METHODS

We developed bariatric surgery models, including gastric banding, sleeve gastrectomy, Roux-en-Y gastric bypass (RYGB), modified RYGB (mRYGB) and biliopancreatic diversion (BPD), in DIO mice. Body weight, body fat and lean mass, liver steatosis, glucose tolerance and pancreatic beta cell function were examined.

RESULTS

All bariatric surgeries resulted in significant weight loss, reduced body fat and improved glucose tolerance in the short term (4 weeks), compared with mice with sham surgery. Of the bariatric surgery models, sleeve gastrectomy and mRYGB had higher success rates and lower mortalities and represent reliable restrictive and gastrointestinal (GI) bypass mouse bariatric surgery models, respectively. In the long term, the GI bypass procedure produced more profound weight loss, significant improvement of glucose tolerance and liver steatosis than the restrictive procedure. DIO mice had increased insulin promoter activity, suggesting overactivation of pancreatic beta cells, which was regulated by the mRYGB procedure. Compared with the restrictive procedure, the GI bypass procedure showed more severe symptoms of malnutrition following bariatric surgery.

DISCUSSIONS

Both restrictive and GI bypass procedures provide positive effects on weight loss, fat composition, liver steatosis and glucose tolerance; however, in the long term, the GI bypass shows better results than restrictive procedures.