Risk and Prophylactic Management of Gallstone Disease in Bariatric Surgery: a Systematic Review and A Bayesian meta-analysis

BACKGROUND

The frequency and management of gallstone disease (GD) in bariatric patients, including the role of routine prophylactic concomitant cholecystectomy (CCY), are still a matter of debate. This study aims to assess the risk of de novo GD in patients undergoing bariatric surgery (BS) and their predictive factors, as well as mortality and morbidity in prophylactic CCY compared to BS alone.

METHODS

We performed a systematic review, searching PubMed, EMBASE, and Web of Science until April 2021. We performed a Bayesian meta-analysis to estimate the risk of GD development after BS and the morbidity and mortality associated with BS alone versus BS + prophylactic CCY. Sources of heterogeneity were explored by meta-regression analysis.

RESULTS

The risk of de novo post bariatric GD was 20.7% (95% credible interval [95% CrI] = 13.0-29.7%; I² = 75.4%), and that of symptomatic GD was 8.2% ([95% CrI] = 5.9-11.1%; I² = 66.9%). Pre-operative average BMI (OR = 1.04; 95% CrI = 0.92-1.17) and female patients' proportion (OR = 1.00; 95% CrI = 0.98-1.04) were not associated with increased risk of symptomatic GD. BS + prophylactic CCY was associated with a 97% probability of a higher number of postoperative major complications compared to BS alone (OR = 1.74, 95% CrI = 0.97-3.55; I² = 56.5%). Mortality was not substantially different between the two approaches (OR = 0.79; 95% CrI = 0.03-3.02; I² = 20.7%).

CONCLUSION

The risk of de novo symptomatic GD after BS is not substantially high. Although mortality is similar between groups, odds of major postoperative complications were higher in patients submitted to BS + prophylactic CCY. It is still arguable if prophylactic CCY is a fitting approach for patients with a preoperative lithiasic gallbladder.

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.

Incidence of symptomatic gallstones after bariatric surgery: the impact of expectant management

BACKGROUND

Bariatric surgery is the most effective treatment for sustained weight reduction and obesity-related comorbidities. The development of gallstones as a result of rapid weight loss is a well-known consequence of bariatric procedures. It remains unclear, if there is an increased risk of these gallstones becoming symptomatic.

METHODS

A retrospective analysis of 505 consecutive patients submitted to either Roux-en-Y Gastric Bypass or Sleeve Gastrectomy between January and December 2019 was performed. The aim of our study was to determine the incidence of symptomatic cholelithiasis in asymptomatic patients with their gallbladder in situ after bariatric surgery and to identify potential risk factors for its development.

RESULTS

Of the 505 patients included, 79 (15.6%) underwent either previous cholecystectomy. (n = 67, 84.8%) or concomitant cholecystectomy during bariatric surgery (n = 12, 15.2%). Among the remaining 426 (84.4%) patients, only 8 (1.9%) became symptomatic during the 12-month follow-up period. When compared with patients who remained asymptomatic, they had a higher median preoperative BMI (47.0 vs. 42.8, p = 0.046) and prevalence of cholelithiasis on preoperative ultrasound (62.5% vs. 10.7%, p = 0.001). Multivariate analysis revealed preoperative BMI and cholelithiasis on preoperative ultrasound as independent risk factors for symptomatic biliary disease (OR 1.187, 95%CI 1.025-1.376, p = 0.022 and OR 10.720, 95%CI 1.613-71.246, p = 0.014, respectively).

CONCLUSION

Considering a low incidence of symptomatic gallstones after bariatric surgery, concomitant cholecystectomy should only be performed in symptomatic patients undergoing bariatric surgery. Preoperative factors, such as a higher BMI and positive ultrasound for cholelithiasis, may be related to the development of symptomatic gallstones.

Comparative Effectiveness of Bariatric Surgeries in Patients with Type 2 Diabetes Mellitus and BMI ≥ 25 kg/m2: a Systematic Review and Network Meta-Analysis

PURPOSE

In patients with type 2 diabetes mellitus (T2DM), bariatric surgery appears to be more effective than medical treatment (MT) at improving glycaemic control and decreasing cardiovascular risk. However, long-term effectiveness has not been systematically assessed using randomised controlled trials. In this study, we aimed to systematically assess randomised controlled trials, with at least 5 years of follow-up, on bariatric surgery in patients with T2DM and BMI ≥ 25 kg/m2, as well as to compare different bariatric procedures.

MATERIAL AND METHODS

PubMed, SCOPUS and Web of Science were searched. We performed a network meta-analysis to evaluate the comparative effectiveness of the different procedures and MT in terms of full T2DM remission, weight loss, complications and cardiometabolic biomarkers. The quality of evidence was assessed using the Cochrane Risk of Bias Tool and CINeMA.

RESULTS

We included 11 primary studies. Laparoscopic one-anastomosis gastric bypass (LOAGB) was found to be one of the most effective treatments for full remission of T2DM (I2 = 0, inconsistency p value = 0.9223). Biliopancreatic diversion without duodenal switch was found to be more effective than laparoscopic Roux-en-Y gastric bypass and laparoscopic adjustable gastric banding regarding percent total cholesterol and low-density lipoprotein change. Regarding percent high-density lipoprotein and weight change, all analysed surgical treatments were shown to be more effective than MT. The confidence rating in our results was overall moderate, but most studies had high risk of performance and detection bias.

CONCLUSION

Bariatric surgery seems to be effective for T2DM remission. LOAGB appears to be a good option in this context, and a possible alternative to laparoscopic duodenal switch, but the included primary studies in our review are not sufficiently powered to establish a more definitive conclusion. More studies with longer follow-up times are needed to comprehensively assess bariatric surgery in T2DM.

Preoperative risk factors for early postoperative bleeding after Roux-en-Y gastric bypass surgery: a systematic review and meta-analysis

PURPOSE

Although bariatric surgery is an effective intervention for obesity, it comes with risks such as early postoperative bleeding (EPB). Identifying preoperative risk factors for this complication can help patients' risk stratification and optimization. We performed a systematic review and meta-analysis to find predictors for early postoperative bleeding after Roux-en-Y gastric bypass (RYGB).

METHODS

We conducted a systematic review, searching PubMed, Cochrane Library, and Web of Science until November 2023. We performed a random-effects meta-analysis to explore preoperative risk factors associated with early postoperative bleeding after RYGB. Sources of heterogeneity were explored by leave-one-out analyses.

RESULTS

23 studies were included, comprising 232,488 patients. Male gender (meta-analytical RR = 1.42, 95%CI = 1.21-1.66, I2 = 18%, Q Cochran test p-value = 0.29) and revisional surgery (meta-analytical RR = 1.35, 95%CI = 1.12-1.62, I2 = 22%, Q Cochran test p = 0.21) were associated with higher risk of EPB. On average, patients with EPB were older than the remainder (MD for the mean age = 2.82 years, 95%CI = 0.97-4.67, I2 = 0.00%, Q Cochran test p = 0.46). Except for hypertension (meta-analytical RR = 1.33, 95%CI = 1.02-1.73, I2 = 66%, Q Cochran test p < 0.0001), comorbidities were not associated with a higher risk of EPB.

CONCLUSION

Preoperative risk factors, including age, gender, hypertension, and revisional bariatric surgery, are associated with early postoperative bleeding after RYGB. Further primary studies, with higher methodological quality, are required to detail more risk factors.

Portomesenteric Venous Thrombosis after Bariatric Surgery: A Case Series and Systematic Review Comparing LSG and LRYGB

(1) Background: Portomesenteric Venous Thrombosis (PMVT) is a rare but serious complication of Metabolic Bariatric Surgery (MBS). Although more frequently reported after laparoscopic sleeve gastrectomy (LSG), the risk factors for PMVT remain unclear. This study aims to compare the incidence and determinants of PMVT between LSG and laparoscopic Roux-en-Y gastric bypass (LRYGB). (2) Methods: A retrospective analysis of 5235 MBSs conducted at our institution between 2015 and 2023 identified five cases of PMVT. Additionally, a systematic review in March 2023, covering PubMed, Web of Science and Scopus, was performed. Several data were analyzed regarding risk factors. (3) Results: In our case series, the incidence of PMVT was 0.1%. The five cases described involved four females with a BMI between 39.7 and 56.0 kg/m2. Their comorbidities were associated with metabolic syndrome, all women used oral contraceptive and two patients were diagnosed with thrombophilia or pulmonary embolism. Per protocol, thromboprophylaxis was administered to all patients. Diagnosis was made at a median of 16 days post-surgery, with abdominal pain being the main presenting symptom. Acute cases were managed with enoxaparin, unfractionated heparin and fibrinolysis. One patient required surgery. Ten studies were included in the systematic review and 205 patients with PMVT were identified: 193 (94.1%) post-LSG and 12 post-LRYGB. The most common comorbidities were dyslipidemia, hypertension, diabetes, sleep apnea and liver disorders; (4) Conclusions: PMVT is a potentially life-threatening complication after MBS, requiring preventive measures, timely diagnosis and several treatments. Our findings suggest a higher occurrence in women with an elevated BMI and post-LSG. Tailored thromboprophylaxis for MBS patients at risk of PMVT may be warranted.

Efficiency and safety of single anastomosis sleeve ileal (SASI) bypass in the treatment of obesity and associated comorbidities: a systematic review and meta-analysis

INTRODUCTION

The Single Anastomosis Sleeve Ileal (SASI) bypass is a new bariatric surgery corresponding to an adaptation of the Santoro approach, consisting of a sleeve gastrectomy (SG) followed by loop gastroileostomy. Therefore, we aimed to systematically assess all the current literature on SASI bypass in terms of safety, weight loss, improvement in associated comorbidities, and complications.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta- Analyses (PRISMA) recommendations, we conducted a systematic review and meta-analysis by searching three databases (PubMed, Scopus, and Web of Science). We performed a meta-analysis of risk ratios and mean differences to compare surgical approaches for excessive weight loss, improvement/remission in type 2 diabetes mellitus (T2DM), hypertension (HT), dyslipidemia (DL), obstructive sleep apnea (OSA), and complications. Heterogeneity was assessed using the I2 statistic.

RESULTS

Eighteen studies were included in the qualitative analysis and four in the quantitative analysis, comparing SASI bypass with SG and One-Anastomosis Gastric Bypass (OAGB). A comparison between Roux-en-Y Gastric Bypass (RYGB) and SASI bypass could not be performed. Compared to SG, the SASI bypass was associated with improved weight loss (MD = 11.32; 95% confidence interval (95%CI) [7.89;14.76]; p < 0.0001), and improvement or remission in T2DM (RR = 1.35; 95%CI [1.07;1.69]; p = 0.011), DL (RR = 1.41; 95%CI [1.00;1.99]; p = 0.048) and OSA (RR = 1.50; 95%CI [1.01;2.22]; p = 0.042). No statistically significant differences in any of the assessed outcomes were observed when compared with OAGB. When compared to both SG and OAGB, the complication rate of SASI was similar.

CONCLUSION

Although studies with longer follow-up periods are needed, this systematic review and meta-analysis showed that SASI bypass has a significant effect on weight loss and metabolic variables. Variations in outcomes between studies reinforce the need for standardization.

The Impact of Cholecystectomy in Patients with Post-Bariatric Surgery Hypoglycemia

BACKGROUND

Metabolic surgery is the foremost treatment for obesity and its associated medical conditions. Nonetheless, post-bariatric hypoglycemia (PBH) emerges as a prevalent complication. PBH pathophysiology implicates heightened insulin and glucagon-like peptide 1 (GLP-1) levels, with bile acids (BA) contributing to GLP-1 release. A plausible association exists between cholecystectomy and PBH, which is attributed to alterations in BA metabolism and ensuing hormonal responses. The objective of this retrospective cohort study was to evaluate the impact of cholecystectomy on PBH pharmacological treatment, diagnostic timelines and metabolic parameters.

MATERIALS AND METHODS

Patients diagnosed with PBH after bariatric surgery were evaluated based on their history of cholecystectomy. Demographic, anthropometric and clinical data were collected. Mixed meal tolerance tests (MMTT) results were compiled to assess metabolic responses.

RESULTS

Of the 131 patients with PBH included in the study, 29 had prior cholecystectomy. The time to PBH diagnosis was similar across groups. Patients with prior cholecystectomy required higher doses of acarbose (p = 0.046), compared to those without prior cholecystectomy. Additionally, MMTT revealed higher insulin (t = 60 min: p = 0.010 and t = 90 min: p = 0.034) and c-peptide levels (t = 60 min: p = 0.008) and greater glycemic variability in patients with prior cholecystectomy (p = 0.049), highlighting the impact of cholecystectomy on glucose metabolism.

CONCLUSION

Our study offers novel insights into PBH pharmacotherapy, indicating that PBH patients with a history of cholecystectomy require elevated doses of acarbose for symptom control than PBH patients without such surgical history. Furthermore, our findings underscore the pivotal role of hyperinsulinism in PBH aetiology, emphasizing the significance of the BA-GLP-1-insulin axis.

O-glicosylation alterations of proteins in gastric carcinoma

62

Background: The expression of immature forms of carbohydrates could help to better understand the biological behavior of gastric cancer.

Methods: From a universe of 50 patients with gastric or gastroesophageal junction carcinoma submitted to surgical treatment between January and October 2009, in our department, 36 out of 38 carcinomas ressected during this period, were selected for a tumor tissue immunohistochemical study of the simple mucin-type carbohydrate antigens (Tn, STn, T and ST) and the Lewis carbohydrate antigens (SLea and SLex). Several clinico-pathological parameters were evaluated according to the expression pattern of the antigens studied.

Results: The ressected gastric carcinomas presented a high incidence of tissue expression of the simple mucin-type and the Lewis carbohydrate antigens, with all cases presenting expression of at least 2 of the antigens and two thirds the expression of 4 or 5. The correlation between the simple mucin-type carbohydrate antigens was high, just as the same as with the Lewis carbohydrate antigens. The analysis of the clinico-pathological profile of gastric carcinomas according to the expression of these antigens revealed the following associations: Tn with venous invasion and perineural invasion; STn with tumor location and macroscopic form; T with age, gender, tumor dimensions and location; ST with macroscopic form and WHO classification; SLea and SLex with the tumor dimensions. Staging of the tumors also revealed associations with the expressions of these antigens: Tn with serosal invasion, lymph node metastases and stage; STn with lymph node ratio; SLea with serosal invasion and lymph node metastases; SLex with depth wall invasion, lymph node metastases and stage. The antigens T e ST did not reveal differences in the expression pattern according to staging.

Conclusions: O-glicosylation alterations of proteins are related with gastric carcinoma, not only their incidence is high but they can also be linked with various clinico-pathological characteristics. The knowledge obtained from this study might serve as a starting point for future investigations taking into account the identification of new biomarkers based on glicosylation alterations of proteins.

No significant financial relationships to disclose.

Assessing Nutritional Deficiencies in Bariatric Surgery Patients: A Comparative Study of Roux-en-Y Gastric Bypass versus Sleeve Gastrectomy

Obesity is a worldwide epidemic, and bariatric surgery is considered the primary treatment for long-term weight loss and managing obesity-related health issues. Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) are the most performed procedures. Nutritional deficiencies are a significant concern following bariatric surgery and can have serious consequences. This study aims to compare the incidence of nutritional deficiencies in patients undergoing RYGB and SG. A retrospective analysis was conducted on the nutritional status of 505 consecutive patients who underwent either RYGB or SG between January and December 2019. Data were collected regarding vitamin B12, folic acid, vitamin D, calcium, PTH, magnesium, hemoglobin, iron, ferritin, and transferrin at preoperative, 6-month, and 12-month intervals post-surgery. The RYGB group showed significantly higher excess weight loss. Vitamin B12, hemoglobin, and ferritin levels were consistently higher in the SG group throughout the study. Vitamin D deficiency was prevalent, with no significant difference between the groups. Vitamin B12 deficiency was significantly more common in the RYGB group (6 months: 17.46% vs. 4.69%, p < 0.001; 12 months: 16.74% vs. 0.93%, p < 0.001). Despite differences in their mechanisms, bariatric surgeries were associated with nutritional deficiencies. It is crucial to efficiently assess, prevent, and manage these deficiencies tailored to each surgical procedure.

Roux-en-Y gastric bypass and sleeve gastrectomy as revisional bariatric procedures after adjustable gastric banding: a retrospective cohort study

INTRODUCTION

The frequency of revisional bariatric surgery is increasing, but its effectiveness and safety are not yet fully established. The aim of our study was to compare short-term outcomes of primary (pRYGB and pSG) and revisional bariatric surgeries (rRYGB and rSG).

METHODS

We performed a retrospective cohort study assessing all patients submitted to primary and revisional (after a failed AGB) RYGB and SG in 2019. Each patient was followed-up at 6 months and 12 months after surgery. We compared pRYGB vs. rRYGB, pSG vs. rSG and rRYGB vs. rSG on weight loss, surgical complications, and resolution of comorbidities.

RESULTS

We assessed 494 patients, of which 18.8% had undergone a revisional procedure. Higher weight loss at 6 and 12 months was observed in patients undergoing primary vs. revisional procedures. Patients submitted to rRYGB lost more weight than those with rSG (%EWL 12 months = 82.6% vs. 69.0%, p < 0.001). Regarding the resolution of obesity-related comorbidities, diabetes resolution was more frequent in pRYGB than rRYGB (54.2% vs. 25.0%; p = 0.038). Also, 41.7% of the patients who underwent rRYGB had dyslipidemia resolution vs. 0% from the rSG group (p = 0.035). Dyslipidemia resolution was also more common in pSG vs. rSG (68.6% vs. 0.0%; p = 0.001). No significant differences in surgical complications were found.

CONCLUSION

Revisional bariatric surgery is effective and safe treating obesity and related comorbidities after AGB. Primary procedures appear to be associated with better weight loss outcomes. Further prospective studies are needed to better understand the role of revisional bariatric surgery.

Nutritional Deficiencies Before and After Metabolic and Bariatric Surgery in Patients Above 50.0 kg/m2: A Single Center Study

Purpose

Metabolic and bariatric surgery (MBS) is an effective treatment for patients with body mass index (BMI) above 50.0 kg/m2 but nutritional deficiencies (ND) may arise. This study aimed to assess if patients with BMI above 50.0 kg/m2 have more ND and require more supplementation after MBS compared to patients in lower BMI groups.

Materials and Methods

Retrospective single center study including all patients submitted to MBS from 2019-2020. Several parameters were collected. Statistical analysis was performed to compare ND between BMI groups (<40.0 kg/m2; 40.0 to 49.9 kg/m2; ≥50.0 kg/m2), and between surgeries (Roux-en-Y gastric bypass [RYGB] vs. sleeve gastrectomy [SG]) in the group with BMI ≥50.0 kg/m2.

Results

We identified 951 patients, 85 (9.0%) with BMI ≥50.0 kg/m2, with RYGB performed in 644 (68.4%) patients. Pre-operatively, vitamin D deficiency was observed in 80.0% of patients with BMI ≥50.0 kg/m2, with significant differences between BMI groups. At follow-up there were no significant differences in ND according to BMI groups. In patients with BMI ≥50.0 kg/m2, vitamin B12 deficiency was more frequent after RYGB. At 2-year follow-up, 95.4% patients were taking multivitamin supplementation, and 52.4% required additional supplements, namely vitamin D.

Conclusion

ND are common in patients with BMI ≥50.0 kg/m2, even before MBS. After surgery, patients with BMI ≥50.0 kg/m2 may not have increased risk for ND, compared to other BMI groups. In these patients, RYGB resulted in an increased risk for vitamin B12 deficiency. Adequate supplementation and clinical follow-up are essential to mitigate these complications.