Oral Hydration, Food Intake, and Nutritional Status Before and After Bariatric Surgery

Gastric Bypass vs Diet and Cardiovascular Risk Factors: A Nonrandomized Controlled Trial

Importance

Roux-en-Y gastric bypass (RYGB) is associated with reduced cardiovascular (CV) risk factors, morbidity, and mortality. Whether these effects are specifically induced by the surgical procedure or the weight loss is unclear.

Objective

To compare 6-week changes in CV risk factors in patients with obesity undergoing matching caloric restriction and weight loss by RYGB or a very low-energy diet (VLED).

Design, Setting, and Participants

This nonrandomized controlled study (Impact of Body Weight, Low Calorie Diet, and Gastric Bypass on Drug Bioavailability, Cardiovascular Risk Factors, and Metabolic Biomarkers [COCKTAIL]) was conducted at a tertiary care obesity center in Norway. Participants were individuals with severe obesity preparing for RYGB or a VLED. Recruitment began February 26, 2015; the first patient visit was on March 18, 2015, and the last patient visit (9-week follow-up) was on August 9, 2017. Data were analyzed from April 30, 2021, through June 29, 2023.

Interventions

VLED alone for 6 weeks or VLED for 6 weeks after RYGB; both interventions were preceded by 3-week LED.

Main Outcomes and Measures

Between-group comparisons of 6-week changes in CV risk factors.

Results

Among 78 patients included in the analyses, the mean (SD) age was 47.5 (9.7) years; 51 (65%) were women, and 27 (35%) were men. Except for a slightly higher mean (SD) body mass index of 44.5 (6.2) in the RYGB group (n = 41) vs 41.9 (5.4) in the VLED group (n = 37), baseline demographic and clinical characteristics were similar between groups. Major atherogenic blood lipids (low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, apolipoprotein B, lipoprotein[a]) were reduced after RYGB in comparison with VLED despite a similar fat mass loss. Mean between-group differences were -17.7 mg/dL (95% CI, -27.9 to -7.5), -17.4 mg/dL (95% CI, -29.8 to -5.0) mg/dL, -9.94 mg/dL (95% CI, -15.75 to -4.14), and geometric mean ratio was 0.55 U/L (95% CI, 0.42 to 0.72), respectively. Changes in glycemic control and blood pressure were similar between groups.

Conclusions and Relevance

This study found that clinically meaningful reductions in major atherogenic blood lipids were demonstrated after RYGB, indicating that RYGB may reduce CV risk independent of weight loss.

Trial Registration

ClinicalTrials.gov Identifier: NCT02386917.

Changes in Nutritional Outcomes After Roux-en-Y Gastric Bypass: A Systematic Review and Meta-Analysis

BACKGROUND

Bariatric surgery (BS) is the most effective treatment for severe obesity and it has beneficial effects on glycemic control and metabolism outcomes. However, the effects of BS on nutritional outcomes are controversial. Therefore, we aimed to evaluate the changes in several nutritional outcomes after Roux-en-Y gastric bypass (RYGB).

METHODS

A comprehensive search was performed using the following databases: PubMed, Embase, Web of Science, Cochrane Library, WanFang and Chinese National Knowledge Infrastructure. The following outcomes were evaluated: vitamin A, 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, parathormone (PTH), iron, ferritin, vitamin B12, folate, and zinc. The pooled outcomes were expressed as standard mean difference (SMD) and 95% confidence interval (CI) using a random effects model.

RESULTS

Fifty-six studies including 5645 individuals with obesity met the inclusion criteria. Serum 25(OH)D (SMD = 0.78, 95%CI 0.38 to 1.20, P < 0.001), phosphorus (SMD = 0.48, 95%CI 0.22 to 0.74, P < 0.001), PTH (SMD = 0.35, 95%CI 0.11 to 0.59, P = 0.005), vitamin B12 (SMD = 1.11, 95%CI 0.41 to 1.80, P = 0.002), and folate (SMD = 1.53, 95%CI 0.77 to 2.28, P < 0.001) significantly increased after RYGB compared with the baseline. Serum ferritin (SMD =  - 1.67, 95%CI - 2.57 to - 0.77, P < 0.001), vitamin A (SMD =  - 0.64, 95%CI - 0.99 to - 0.29, P < 0.001), and plasma zinc (SMD =  - 0.58, 95%CI - 1.09 to - 0.06, P = 0.027) significantly decreased after RYGB. No significant changes in serum calcium (SMD =  - 0.14, 95%CI - 0.40 to 0.11, P = 0.219) and iron (SMD = 0.26, 95%CI - 0.11 to 0.64, P = 0.165) were observed after RYGB.

CONCLUSIONS

Despite the increased levels of 25(OH)D, phosphorus, vitamin B12 and folate, this meta-analysis revealed the unfavorable nutritional consequences after RYGB.

Micronutrient status 2 years after bariatric surgery: a prospective nutritional assessment

Background

Among commonly performed bariatric surgeries, biliopancreatic diversion with duodenal switch (BPD-DS) provides greater weight loss than Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG), with sustained metabolic improvements. However, the risk of long-term nutritional deficiencies due to the hypoabsorptive component of BPD-DS hinders its widespread use.

Objective

The aim of the study was to examine nutritional status over 2 years after BPD-DS, RYGB or SG.

Methods

Patients were recruited in the REMISSION trial (NCT02390973), a single-center, prospective study. Out of 215 patients, 73, 48 and 94, respectively, underwent BPD-DS, RYGB or SG. Weight loss, micronutrient serum levels (including iron, calcium, parathormone, vitamins A, B12 and D), and nutritional supplementation were assessed over 2 years. Patients were supplemented according to the type of surgery and individual micronutrient level evolution.

Results

At baseline, BPD-DS patients were younger than SG patients (p = 0.0051) and RYGB patients had lower body mass index (p < 0.001). Groups had similar micronutrient levels before surgery, with vitamin D insufficiency as the most prevalent nutritional problem (SG: 38.3%, RYGB: 39.9%, BPD-DS: 54.8%, p = 0.08). BPD-DS patients showed lower levels of iron, calcium and vitamin A than SG patients at 24 months. Groups had similar levels of vitamin D at 24 months. Prevalence of vitamin D, calcium, iron, vitamin A and vitamin B12 deficiency was similar among groups at 24 months. Rates of vitamin D insufficiency and iron deficiency were lower at 24 months than at baseline. Micronutrient intake was consistent with recommendations in groups post-surgery, but most BPD-DS patients took vitamin A and vitamin D supplement doses above initial recommendations.

Conclusion

With appropriate medical and nutritional management, all surgeries led to similar rates of vitamin D, calcium, iron, vitamin A and vitamin B12 deficiencies at 24 months. However, initial vitamin A and vitamin D supplementation recommendations for BPD-DS patients should be revised upwards.

Change in Mineral Status After Bariatric Surgery: a Meta-analysis

BACKGROUND

The risk of protein and vitamin deficiencies after bariatric surgery has been well studied, but the change in mineral status has not gotten enough attention. This study aimed to perform a meta-analysis regarding the change in mineral levels after bariatric surgery and the prevalence of postoperative mineral deficiency, with subgroup analyses of different surgical procedures, study regions, and follow-up time.

METHODS

CENTRAL, PubMed, and EMBASE were searched for related articles. Meta-analysis, subgroup analysis, and sensitivity analysis were performed if necessary.

RESULTS

A total of 107 articles with 47,432 patients were included. The most severe mineral deficiency after bariatric surgery was iron (20.1%), followed by zinc (18.3%), copper (14.4%), chlorine (12.2%), phosphorus (7.5%), and calcium (7.4%). Serum concentrations of potassium, sodium, selenium, manganese, and molybdenum showed no significant change before and after surgery. Subgroup analyses revealed that SG had fewer deficiencies in serum iron, calcium, zinc, magnesium, phosphorus, copper, and selenium than RYGB. OAGB showed a higher incidence of serum iron and zinc deficiencies than RYGB. Studies conducted in different regions also found various mineral statuses after surgery. Studies with follow-up ≥ 5 years had a lower prevalence of zinc, copper, and selenium deficiencies than follow-up < 5 years.

CONCLUSION

A high deficiency rate of serum iron, zinc, copper, chlorine, phosphorus, and calcium was seen after bariatric surgery. The difference in surgical procedures, study regions, and follow-up time may affect postoperative mineral status; more targeted mineral supplement programs are needed considering these influencing factors.

Prevalence and associated factors of vitamin D deficiency after Roux-en-Y gastric bypass: a systematic review and meta-analysis

OBJECTS

To estimate the prevalence and associated factors of vitamin D deficiency (VDD) after Roux-en-Y gastric bypass (RYGB).

METHODS

PubMed, EMBASE, and CENTRAL were searched for relevant records from inception to 17 March 2023, using search terms: vitamin D, vitamin D3, vitamin D deficiency, hypovitaminosis D, gastric bypass, and RYGB. Studies were eligible for inclusion if they provided related data on VDD prevalence after RYGB.

RESULTS

Of the 1119 screened studies, 72 studies involving 7688 individuals were enrolled in the final analysis. The prevalence estimates of VDD after RYGB were 42%. Subgroup analyses suggested the pooled prevalence of postoperative VDD was 35% for follow-up duration less than or equal to 1 year, 43% for greater than 1 and less than or equal to 5 years, and 54% for greater than 5 years. Meta-regression showed that VDD prevalence was positively correlated with follow-up time. Also, the prevalence was higher in studies with inadequate vitamin D supplementation than in those with adequate supplementation and in Asia population than in those from South America, Europe, and North America. Other factors associated with high VDD prevalence after RYGB included high presurgical VDD prevalence, noncompliant patients, and black populations. No significant association existed between VDD and alimentary length.

CONCLUSION

VDD presented a high prevalence in patients following RYGB. It occurred more frequently with longer postoperative follow-up time. Population-specific vitamin D supplementation measures, targeted treatment for presurgical VDD, improved patient compliance, and periodical follow-ups were necessary to reduce VDD and other adverse outcomes.

Factors Involved in the Evolution of the Basal Metabolic Rate over 30 Months After Roux-en-Y Gastric Bypass

INTRODUCTION

After Roux-en-Y gastric bypass (RYGB), the basal metabolic rate (BMR) falls. However, it is important to know how BMR per kilogram of body weight (BMR/kg) varies in the postoperative period. The present study evaluated the changes in the BMR/kg and its correlates over 30 months after RYGB.

METHODS

Eighty adult patients of both genders who underwent RYGB agreed to participate in the study. The following evaluations were performed before surgery (n=48) and 6 (n=27), 12 (n=28), 24 (n=40), and 30 months (n=29) after surgery: anthropometry, body composition (bioelectrical impedance), metabolic analysis (indirect calorimetry), and diet (food recall). Statistical analysis was performed (p = 0.05).

RESULTS

Although BMR decreased after surgery, BMR/kg increased significantly as compared to baseline from 12 months onward, peaking at 24 months and not significantly dipping at 30 months, suggesting stabilization of BMR/kg 2 years after surgery (pre, 10.68 ± 2.33 kcal/kg; 12 months, 12.46 ± 2.85 kcal/kg; 24 months, 18.78 ± 4.81 kcal/kg; 30 months, 18.12 ± 3.69 kcal/kg; p <0.001). Regarding the variables that influenced the BMR/kg, at 12 months, they were %LBM and intake of calcium-source foods (34%); at 24 months, it was protein intake (16%); and at 30 months, it was the intake of calcium-source foods (26.7%).

CONCLUSION

RYGB is associated with a significant increase in BMR when it is adjusted to body weight from 12 to 24 months postoperatively. Among the factors involved in the increase in BMR/kg are body composition and intake of protein-rich foods.

A Systematic Review and Meta-Analysis of Vitamin D Status of Patients with Severe Obesity in Various Regions Worldwide

INTRODUCTION

Managing nutritional deficiencies is an essential component in the treatment of severe obesity. Vitamin D deficiency is often reported in investigations in severely obese cohorts. However, no prior study has summarized findings on this topic. Consequently, the aim of this systematic review and meta-analysis was to investigate the 25-hydroxyvitamin D [25(OH)D] status in individuals with severe obesity in different regions worldwide. We also evaluated levels of calcium, parathyroid hormone (PTH), and magnesium as secondary outcome measures.

METHODS

We searched Medline, PubMed, Scopus, the Cochrane Library, and EMBASE for relevant observational studies published in English from 2009 to October 2021. The heterogeneity index among the studies was determined using the Cochran (Q) and I2 tests. Based on the heterogeneity results, the random-effect model was applied to estimate the prevalence of vitamin D deficiency.

RESULTS

We identified 109 eligible observational studies. Overall, 59.44% of patients had vitamin D deficiency [25(OH)D <20 ng/mL], whereas 26.95% had vitamin D insufficiency [25(OH)D 20-30 ng/mL]. Moreover, the mean 25(OH)D level was 18.65 ng/mL in 96 studies. The pooled mean estimate of the serum calcium, PTH, and magnesium was 9.26 mg/dL (95% confidence interval [CI]: 9.19-9.32, I2 = 99.7%, p < 0.001), 59.24 pg/mL (95% CI: 54.98, 63.51, I2 = 99.7%, p < 0.001), and 0.91 mg/dL (95% CI: 0.84, 0.98, I2 = 100.0%, p < 0.001), respectively. The results of the subgroup analysis indicated that the mean estimates of 25(OH)D were highest in North America (21.71 ng/mL [19.69, 23.74], [I2 = 97.2%, p < 0.001]) and lowest in Southeast Asia (14.93 ng/mL [14.54, 15.33], [I2 = 0.0%, p = 0.778]).

CONCLUSION

The results obtained showed a significant prevalence of vitamin D deficiency among severely obese individuals in various geographical regions, whereas the highest and lowest mean estimates were reported for North America and Southeast Asia, respectively.

Nutritional Intervention for a Patient With Sleeve Gastrectomy

Bariatric surgery is the most effective treatment for sustained weight reduction, and it can result in substantial improvements in the severity of type 2 diabetes, metabolic syndrome, nonalcoholic fatty liver disease, and quality of life. However, sleeve gastrectomy, a weight loss surgery that removes two-thirds of the stomach, reduces appetite and nutrient absorption, impairing digestion and the absorption of nutrients like iron, vitamin B12, and protein-bound nutrients. This case study aims to demonstrate that patients undergoing sleeve gastrectomy require long-term and periodic monitoring of biochemical data, weight changes, and caloric and protein intake by a professional nutritionist to prevent malnutrition and nutritional deficiencies. In this case study, a 48-year-old woman was diagnosed with morbid obesity, hypertension, sleep apnea syndrome, and chronic gastritis. At initial evaluation, she was 160 cm tall and weighed 89 kg, with a body mass index of 34.8 kg/m2. At 1 postoperative year, she consumed 650 kcal and 25 g of protein per day, the percentage of excess weight loss was 141.1%, and body mass index was 21 kg/m2. Compared to preoperative levels, calcium and folic acid levels did not decrease after 1 postoperative year, but hemoglobin, ferritin, and vitamin B12 levels decreased. In conclusion, when patients experience rapid weight loss after sleeve gastrectomy, follow-up should be frequent and long. Dietary education should be conducted according to digestive symptoms, and oral nutritional supplements, including vitamins and minerals.

Assessment of the Clinical Condition and Way of Patients' Nutrition before and after Laparoscopic Sleeve Gastrectomy

One of the most commonly performed bariatric procedures is the laparoscopic sleeve gastrectomy (LSG). It is highly effective in reducing body weight, but it carries the risk of developing nutritional deficiencies and their consequences. The aim of the study was to determine the clinical condition of obese patients after LSG in terms of nutritional status, metabolic disorders, and way of nutrition. Thirty participants (15 women and 15 men) took part in the study. A statistically significant reduction in the total body fat mass (women by 37.5% p < 0.05, men by 37.06% p < 0.05) and total fat free mass (women by 10% p < 0,05, men by 12.5% p < 0.05) was demonstrated 6 months after LSG. Moreover, insufficient protein intake has been shown in over 73% of women and 40% of men. Before and 6 months after LSG, insufficient intake of calcium, magnesium, potassium, folate, vitamin D, and iron was observed. Six months after the LSG, significant decreases of fasting glucose (p < 0.05), insulin (p < 0.05), TG (p < 0.05), and AST (p < 0.05) concentrations, were observed in both groups. Optimization of nutrition in order to prevent nutritional deficiencies and their complications is a key element of the therapy of obese patients treated surgically.

Does Bypass of the Proximal Small Intestine Impact Food Intake, Preference, and Taste Function in Humans? An Experimental Medicine Study Using the Duodenal-Jejunal Bypass Liner

The duodenal-jejunal bypass liner (Endobarrier) is an endoscopic treatment for obesity and type 2 diabetes mellitus (T2DM). It creates exclusion of the proximal small intestine similar to that after Roux-en-Y Gastric Bypass (RYGB) surgery. The objective of this study was to employ a reductionist approach to determine whether bypass of the proximal intestine is the component conferring the effects of RYGB on food intake and sweet taste preference using the Endobarrier as a research tool. A nested mechanistic study within a large randomised controlled trial compared the impact of lifestyle modification with vs. without Endobarrier insertion in patients with obesity and T2DM. Forty-seven participants were randomised and assessed at several timepoints using direct and indirect assessments of food intake, food preference and taste function. Patients within the Endobarrier group lost numerically more weight compared to the control group. Using food diaries, our results demonstrated similar reductions of food intake in both groups. There were no significant differences in food preference and sensory, appetitive reward, or consummatory reward domain of sweet taste function between groups or changes within groups. In conclusion, the superior weight loss seen in patients with obesity and T2DM who underwent the Endobarrier insertion was not due to a reduction in energy intake or change in food preferences.

Vitamin B Complex Deficiency After Roux-en-Y Gastric Bypass and Sleeve Gastrectomy-a Systematic Review and Meta-Analysis

Bariatric surgery, although an effective method, still has complications, like nutritional deficiencies. Our aim was to summarize the evidence on the frequency of complex B vitamin deficiencies in studies comparing Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). We included 25 studies for qualitative synthesis and 21 studies for quantitative synthesis. Relevant data was extracted, including proportion of patients with deficiency and mean serum vitamin values in 3 different timeframes. B12 and folate were the most prevalent deficiencies. B12 deficiency was more common after RYGB and folate serum mean levels were higher after RYGB. SG causes less nutrient deficiency and is therefore a better technique from this point of view. More studies are needed on B2, B3, and B6 vitamins to draw better conclusions.

Changes in Nutritional Outcomes After Sleeve Gastrectomy: a Systematic Review and Meta-analysis

PURPOSE

The aim of this meta-analysis is to evaluate the changes in nutritional indicators in individuals with obesity before and after SG.

MATERIALS AND METHODS

A systematic retrieval of the available literature was performed using PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure databases. The following indicators were evaluated: serum 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, iron, vitamin B12, folate, magnesium, and zinc from pre-operation to post-operation.

RESULTS

A total of 38 studies met inclusion criteria. A significant increase was observed in serum 25(OH)D (SMD = 0.70, 95%CI 0.38 to 1.02, P < 0.001), phosphorus (SMD = 0.40, 95%CI 0.14 to 0.67, P = 0.003), iron (SMD = 0.50, 95%CI 0.38 to 0.62, P < 0.001), and folate (SMD = 0.37, 95%CI 0.09 to 0.65, P = 0.01) after SG. Nevertheless, the increasing trend of serum phosphorus (P = 0.143) and folate (P = 0.774) disappeared in the unprescribed subgroup. A significant decrease in serum zinc (SMD =  - 0.41, 95%CI - 0.81 to - 0.01, P = 0.044) was found after SG. No significant changes in serum calcium (SMD = 0.08, 95%CI - 0.09 to 0.25, P = 0.372), vitamin B12 (SMD = 0.10, 95%CI - 0.13 to 0.33, P = 0.398), and magnesium (SMD = 0.24, 95%CI - 0.10 to 0.58, P = 0.169) were observed. However, a significant decrease in serum calcium (P = 0.042) and vitamin B12 (P = 0.037) was found in the unprescribed subgroup.

CONCLUSIONS

Serum 25(OH)D, phosphorus, iron, and folate levels improved after a careful monitoring and due to a rigorous supplementation. The optimal dose of calcium, magnesium, and zinc supplementation has yet to be established; therefore, a broader supplementation of trace elements and minerals has to be suggested.

Nutritional Deficiencies Among Adolescents Before and After Sleeve Gastrectomy: First Study with 9-Year Follow-up

BACKGROUND

Globally, only two studies appraised the long-term nutritional status of adolescents after laparoscopic sleeve gastrectomy (LSG).

METHODS

Retrospective chart review of all adolescents aged ≤ 18 years who underwent LSG with ≥ 5 years follow-up and had no subsequent revisional surgery (N = 146). We assessed 15 nutritional parameters preoperatively and at 1, 3, 5, 7, and 9 years post surgery.

RESULTS

Mean age was 16.51 ± 1.29 years, 51% were males. We identified three patterns: 1) Significant worsening of preoperative deficiencies: 4.7% and 0.8% of the sample exhibited zinc and vitamin B12 deficiencies, worsening to 20.8% and 12.8% at 1 year, respectively. Likewise, 0.7% of the sample had low total protein, worsening to 8.3% at year 3. A total of 32.4% of females had preoperative low hemoglobin worsening to 57.9% at year 5. 2) Significant improvement: the percentage of males with preoperative low hemoglobin (5.6%) was reduced to 4.1% and 5.1% at years 1 and 3, respectively. 3) Persistent deficiency: all (100%) of adolescents had preoperative vitamin D deficiency that persisted through years 3 and 9 at 90.5% and 100%, respectively. The most common complications were food intolerance (51%), vomiting (47.5%), gastritis/ esophagitis (35.7%), and gastroesophageal reflux disease (20.3%). We observed one case of Wernicke's encephalopathy. Across the 9 years, 15.4% of the adolescents underwent intra-abdominal surgeries where 12.6% had cholecystectomy and one patient had appendectomy.

CONCLUSION

Adolescents had several preoperative nutritional deficiencies, most of which worsened or persisted on the long term. This is the first study among adolescents to assess such deficiencies beyond 5 years.

Macro- and Micro-nutrient Intake Adequacy in Gastric Bypass Patients after 24 Months: a Cross-sectional Study

Decreased food intake is an effective mechanism for gastric bypass surgery (GBS) for successful weight loss. This cross-sectional study aimed to assess dietary intake, micro-and macro-nutrients in the patients undergoing GBS and determine the possible associations with weight changes. We assessed anthropometric indices and food intake at 24 month-post gastric bypass surgery. Dietary data was evaluated using three-day food records. After the 24 months of surgery, among 35 patients (mean age: 43.5 ± 11.2 years; 82.85% females), with the mean body mass index (BMI) of 30.5 ± 4.5 kg/m², 17 cases were < 50% of their excess weight. The average daily calorie intake was 1,733 ± 630 kcal, with 14.88% of calories from protein. Consumption amounts of protein (0.82 ± 0.27 g/kg of the current weight), as well as fiber, and some micro-nutrients (vitamin B9, E, K, B5, and D3) were lower than recommended amounts. Patients were classified into three groups based on their success in weight loss after surgery. Calorie intake was not significantly different between groups, but successful groups consumed considerably more protein and less carbohydrate than the unsuccessful group (p < 0.05). Based on our findings, the patients undergoing GBS had inadequate macro- and micro-nutrient intake after 24 months. However, protein intake can affect patients' success in achieving better weight loss. Long-term cohort and clinical studies need to be conducted to comprehend this process further.

Micronutrient status in bariatric surgery patients receiving postoperative supplementation per guidelines: Insights from a systematic review and meta-analysis of longitudinal studies

The micronutrient status and optimal monitoring schedule after bariatric surgery have not been sufficiently assessed. This systematic review and meta-analysis investigated the longitudinal changes in micronutrient status after bariatric surgery. PubMed, EMBASE, and Cochrane Library were searched for articles that measured preoperative and postoperative serum micronutrient levels in patients undergoing Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). Among guideline-adherent studies, the longitudinal changes in micronutrient status were investigated using weighted mean difference (WMD) using a random-effects model. Among the 82 included studies, the guideline adherence rates for micronutrient supplementation after bariatric surgery did not exceed 20%. In patients supplemented per guidelines, vitamin A significantly decreased after RYGB by -7.54 (95% confidence interval [CI], -10.16 to -4.92) μg/dl at 12-23 months, vitamin E decreased after RYGB by -2.35 (95% CI, -3.65 to -1.05) μg/dl at ≥24 months, and ferritin by -54.93 (95% CI, -77.19 to -32.67] μg/L at ≥24 months after SG, compared with baseline, with moderate level of evidence. Significant decreases in micronutrient levels at certain follow-up intervals in studies with supplementation per guidelines need to be considered to establish a post-bariatric micronutrient monitoring schedule for timely detection and management of micronutrient deficiencies.

Evaluation of Dietary Assessment Tools Used in Bariatric Population

Severe obesity is associated with major health issues and bariatric surgery is still the only treatment to offer significant and durable weight loss. Assessment of dietary intakes is an important component of the bariatric surgery process. Objective: To document the dietary assessment tools that have been used with patients targeted for bariatric surgery and patients who had bariatric surgery and explore the extent to which these tools have been validated. Methods: A literature search was conducted to identify studies that used a dietary assessment tool with patients targeted for bariatric surgery or who had bariatric surgery. Results: 108 studies were included. Among all studies included, 27 used a dietary assessment tool that had been validated either as part of the study per se (n = 11) or in a previous study (n = 16). Every tool validated per se in the cited studies was validated among a bariatric population, while none of the tools validated in previous studies were validated in this population. Conclusion: Few studies in bariatric populations used a dietary assessment tool that had been validated in this population. Additional studies are needed to develop valid and robust dietary assessment tools to improve the quality of nutritional studies among bariatric patients.

Nutritional consequences of endoluminal gastroplasty in the treatment of morbidly obese patients

BACKGROUND

The Endoscopic sleeve gastroplasty (ESG) is one of the new advanced restrictive techniques of bariatric endoscopy. The principle of this bariatric technique is the reduction of stomach volume through endoscopic plication. The long-term efficacy and metabolic effects of this procedure are the subject of this study.

METHODS

20 patients were enrolled; four men, sixteen women. Then they were followed for 24 months in terms of glycemic control, body composition, vitamin, and nutritional status. Observed parameters included glucose, triacylglycerols, high- and low-density lipoprotein cholesterol, micro and macro nutrients, fat mass, and lean body mass.

RESULTS

We observed significant weight loss and a decrease body composition resulted from procedure vs. baseline, with levels of blood glucose also showing statistically significant reductions. The most notable decline in measured values was observed in period six months after the procedure. No significant changes were observed in measurement of micronutrients.

CONCLUSIONS

Good restriction results were obtained following ESG, which might be mediated via altered glucose metabolism. The ESG method has shown a positive effect on fat and muscle mass. Unlike surgical methods, there were no deficits or deficiencies, especially in terms of essential vitamin levels.

A Qualitative Exploration of Patients' Experiences with Lifestyle Changes After Sleeve Gastrectomy in China

PURPOSE

Sleeve gastrectomy (SG) is the most widely used surgical treatment for severe obesity worldwide. Individuals who have undergone SG usually need to change lifestyle behaviors as a response to the anatomical changes imposed by SG, and patients need to sustain lifestyle changes for long-term surgical success. Little is known about how patients experience and manage lifestyle changes following SG. In China, where SG comprises over 70% of bariatric surgical procedures, there have been no reports addressing this issue. This study aimed to describe individuals' experiences related to lifestyle changes after SG in China.

MATERIALS AND METHODS

Semi-structured interviews were conducted at the Shanghai Huashan Hospital in China with adults who had undergone SG between 2012 and 2018. Two independent researchers used an interpretive thematic approach to analyze transcripts for themes and sub-themes.

RESULTS

Interviews (N = 15) revealed three major themes of participants' experiences with postoperative lifestyle changes: advantages outweigh disadvantages; developing self-management strategies (i.e., adopting new behaviors and developing habits, continuing self-monitoring, focusing on health over weight, staying determined); and experiencing culture-specific difficulties in adherence to follow-up visits and lifestyle recommendations.

CONCLUSION

The data from this study provided a rich description of the postoperative experiences of patients in China. Participants reported that surgical benefits supersede the surgery-related side effects, and participants were able to develop self-management strategies in order to achieve success. However, personal and social barriers, such as the challenges of applying postoperative dietary guidelines into daily practice, may impede patients making and sustaining recommended behavioral changes.

Vitamin E status among bariatric surgery patients: a systematic review

Vitamin E, a fat-soluble vitamin with antioxidant properties, is thought to modulate enzymes involved in signal transduction, affect gene expression, and have immunomodulatory capabilities. Severe vitamin E deficiency is associated with neuronal disorders, impaired immune response, hemolytic anemia, and oxidative-based disorders. Patients who undergo bariatric surgery (BS), especially malabsorptive procedures, are at greater risk of developing fat-soluble vitamin deficiencies. Current data on vitamin E statuses among BS patients are limited. Therefore, this systematic review has summarized the scientific literature on vitamin E and examined its status among patients following different types of BS. Searches of the MEDLINE and Embase databases were performed, followed by hand-searching of reference lists from all relevant papers. Of the 671 initially identified articles, 24 met the inclusion criteria: 1 study on adjustable gastric banding patients (n = 21), 4 studies on sleeve gastrectomy patients (n = 173), 12 studies on Roux-en-Y gastric bypass patients (n = 689) and 12 studies on biliopancreatic diversion with or without duodenal switch (n = 799) or single anastomosis duodeno-ileal bypass with sleeve gastrectomy patients (n = 163). Results suggest that patients who undergo malabsorptive procedures are at higher risk of developing vitamin E deficiency, although clinical manifestations of vitamin E deficits following BS are rarely documented. The optimal dose of vitamin E supplementation required for prevention of deficiency or for treatment following BS has yet to be established. Future observational and intervention studies are needed to bridge the gaps in existing knowledge.

Obesity, Hypertension, and Bariatric Surgery

PURPOSE OF REVIEW

Obesity increases the risk of hypertension. However, blood pressure decreases before any significant loss of body weight after bariatric surgery. We review the mechanisms of the temporal dissociation between blood pressure and body weight after bariatric surgery.

RECENT FINDINGS

Restrictive and bypass bariatric surgery lower blood pressure and plasma leptin levels within days of the procedure in both hypertensive and normotensive morbidly obese patients. Rapidly decreasing plasma leptin levels and minimal loss of body weight point to reduced sympathetic nervous system activity as the underlying mechanism of rapid blood pressure decline after bariatric surgery. After the early rapid decline, blood pressure does not decrease further in patients who, while still obese, experience a steady loss of body weight for the subsequent 12 months. The divergent effects of bariatric surgery on blood pressure and body weight query the role of excess body weight in the pathobiology of the obesity phenotype of hypertension. The decrease in blood pressure after bariatric surgery is moderate and independent of body weight. The lack of temporal relationship between blood pressure reduction and loss of body weight for 12 months after sleeve gastrectomy questions the nature of the mechanisms underlying obesity-associated hypertension.

Weight Loss After RYGB Is Associated with an Increase in Serum Vitamin D in a Population with Low Prevalence of Hypovitaminosis D at Low Latitude

PURPOSE

In Brazil and worldwide, few studies have investigated vitamin D deficiency in patients with severe obesity who underwent bariatric surgery associated with latitude and level of solar radiation. The objective of this study was to investigate the prevalence of vitamin D deficiency and the predictive factors of serum level changes after 12 months of RYGB in a low latitude region.

MATERIALS AND METHODS

This study included 50 patients from a low-latitude city (10° 10' 8″ S) in the north of Brazil. We collected data before surgery and after 3 and 12 months of surgery. The level of vitamin D was classified as deficiency (< 20 ng/ml), insufficiency (20-30 ng/ml), and sufficiency (≥ 30 ng/ml).

RESULTS

The mean age of the patients was 38.7 ± 8.9 years, 69% were women, and percent excess weight loss (% EWL) was 83% after 1 year of surgery. The prevalence of vitamin D deficiency in the preoperative period was 14%, and after 3 and 12 months of surgery, it decreased to 4% and 6%, respectively. The variation in vitamin D after 12 months of surgery was positively associated with changes in BMI, body fat, and % EWL.

CONCLUSIONS

The prevalence of vitamin D deficiency is low in patients undergoing bariatric surgery in the northern region of Brazil, which is possibly related to low latitude. Weight loss was positively associated with an increase in serum vitamin D after surgery.

Missing Something? Comparisons of Effectiveness and Outcomes of Bariatric Surgery Procedures and Their Preferred Reporting: Refining the Evidence Base

Comparisons of effectiveness of bariatric surgery (BS) procedures encompass weight loss, metabolic/clinical outcomes, and improvements or worsening of comorbidities. Post-operative physical activity (PA) and diet influence such outcomes but are frequently not included in comparisons of effectiveness. We assessed the value and necessity of including post-operative PA/diet data when comparing effectiveness of BS. Including post-operative PA/diet data has significant benefits for BS and patients. The paper proposes an explicit preferred reporting system (Preferred REporting of post-operative PHYsical activity and Diet data in comparisons of BS effectiveness: PRE-PHYD Bariatric). Including post-operative PA/diet data could result in more accurate appraisals of effectiveness of BS procedures. This could translate into better 'individualized' BS by achieving a better 'fit' between patient and procedure.