Michelle Teixeira Frota Reichmann

Metabolic bariatric surgery is considered the most effective treatment for severe obesity, however it may be associated with the development of Small Intestinal Bacterial Overgrowth (SIBO) and other gastrointestinal symptoms (GIS). This study conducted a systematic review and meta-analysis to evaluate the effects of probiotics or synbiotics on GIS and SIBO in post- metabolic bariatric surgery patients. Five studies that investigated the effect of probiotics or synbiotics in the treatment of post-surgery GIS were included in the review, with three focusing on SIBO. For the meta-analysis, three studies assessed GIS, and two examined SIBO. The results showed that probiotics did not offer significant benefits in treating GIS or SIBO in these patients.

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. Graphical Abstract

Patients who undergo Roux-en-Y gastric bypass (RYGB) exhibit a reduction in total basal metabolic rate (BMR) after surgery, which seems to be intimately related to the amount of postoperative weight loss. The objective was to perform a systematic review and meta-analysis of the literature to determine and evaluate BMR changes after RYGB. The search was performed in certified databases, and the strategy was structured according to the PRISMA ScR. The quality evaluation of the articles included in this review was assessed with two different bias risk tools (ROBINS-I and NIH) according to each study design. Two meta-analyses were elaborated based on the results. 163 articles were selected (from 2016 to 2020), and 9 articles met the inclusion criteria. All of the selected studies evaluated only adult patients, mostly women. Postoperative BMR diminished in all of the included studies after surgery compared to preoperative values. The follow-up periods were 6, 12, 24 and 36 months. Eight articles were used for the meta-analysis after the quality assessment, a total of 434 participants. Compared to baseline values, mean postoperative reductions of 356.66 kcal/d after 6 months (p < 0.001) and 432.89 kcal/d (p < 0.001) after 1 year were observed. The BMR decreases during the first years after Roux-en-Y gastric bypass, especially during the first year postsurgery.

Introduction: the Roux-en-Y gastric bypass (RYGB) is considered to be an efficient treatment of obesity. There is an improvement in the dietary intake in the immediate postoperative period, but after the first year there is a tendency to return to the old pre-surgery habits. The objective of the present study was to compare the dietary intake of women in the late postoperative period after RYGB with the recommendations of the specific bariatric food pyramid. Methodology: the whole population of patients submitted to RYGB being accompanied by two out-patients departments of the Complexo Hospital de Clinicas of Universidade Federal do Parana in the period from March to September 2017 were considered, selecting only those who conformed to the inclusion criteria. The analyses carried out were: the hospital records, anthropometric evaluation, basal metabolic rate by indirect calorimetry, food consumption and questionnaires concerning physical activity, food intolerance and the dumping syndrome. The food consumption was separated into food groups in order to compare with the specific pyramid. Descriptive analyses were used to characterize the sample. Results: it can be seen that the percent of macronutrients in relation to the total energy value (TEV) was within the values established by the recommended dietary allowances (RDA), although with respect to fiber, 68% of the participants showed a consumption below the adequate intake (AI). Inadequacy was observed for practically all the components when comparing the number of portions per food group of the bariatric pyramid, with the exception of the protein group. Conclusion: after RYGB, the dietary consumption was compromised in quantity and quality. In addition, in the late postoperative period, women tended to choose high calorie dense foods poor in fiber, a fact that is aggravated by the presence of food intolerances.