Welcome to our weekly round-up of the latest bariatric and obesity-related papers published in the medical literature. As ever, we have looked far and wide to give you an overview of papers including an IFSO report on the benefits of registries, preoperative depression, the role of gastrin, preoperative comorbidities as a predictor of EBWL, prediction model for postoperative nausea and vomiting, and semaglutide trials, and more (please note, log-in maybe required to access the full paper).
Metabolic Bariatric Surgery Across the IFSO Chapters: Key Insights on the Baseline Patient Demographics, Procedure Types, and Mortality from the Eighth IFSO Global Registry Report
Registries enable meaningful comparisons between countries on the demographics, characteristics, operation types and approaches, and trends in MBS procedures, according to the latest outcomes from the IFSO Global Registry Collaboration.
Writing in Obesity Surgery, data was collected from 24 national and two regional registries, providing information on 502,150 procedures. The most performed primary MBS procedure was sleeve gastrectomy, whereas the most performed revisional MBS procedure was Roux-en-Y gastric bypass. Asian countries reported people with lower BMI undergoing MBS along with higher rates of diabetes. Mortality was a rare event.
Reported outcomes from these registries can be seen as indicators of potential issues or relationships that could be studied in more detail in specific research studies.
To access this paper, please click here
Preoperative depression and outcomes after metabolic and bariatric surgery: A systematic narrative review
While the impact of preoperative depression on weight loss after MBS remains unclear, there is early evidence that depression has negative consequences on other patient-important outcomes, according to researchers from the University of Toronto, Toronto, Canada.
Reporting in Obesity Reviews, the researcher identified 18 studies (5 prospective and 13 retrospective) reporting on 5933 participants were included. Most participants underwent gastric bypass or sleeve gastrectomy. Meta-analyses were not conducted due to heterogeneity in reported outcomes; findings were instead synthesized using a narrative and tabular approach.
Across 13 studies (n = 3390) the associations between preoperative depression and weight loss outcomes at 6–72 months were mixed overall. This may be related to differences in cohort characteristics, outcome definitions, and instruments used to measure depression. A small number of studies reported that preoperative depression was associated with lower quality of life, worse acute pain, and more perioperative complications after surgery. Most of the included studies were deemed to be at high risk of bias, resulting in low or very low certainty of evidence according to the Risk of Bias In Non-randomized Studies - of Exposure (ROBINS-E) tool.
Adequately powered studies using more sophisticated statistical methods are needed to accurately estimate these associations.
To access this paper, please click here
Gastrin: a new branch of the gastropancreatic axis that can explain the effect of sleeve gastrectomy on glucose metabolism
Spanish researchers have reported that gastrin plays a central role in glucose improvement after SG, writing in the Journal of Gastrointestinal Surgery.
Gastrin induces insulin release in isolated pancreatic islets, limiting somatostatin-14 intraislet release, and has been associated with blood glucose level improvement in diabetic models after SG. This study aimed to determine the role of gastrin in glucose metabolism improvement after SG with the aid of the gastrin antagonist netazepide.
In 12 sham-operated, 12 SG-operated, and 12 SG-operated/netazepide-treated Wistar rats, they compared medium- and long-term plasma insulin, oral glucose tolerance test (OGTT) results and plasma gastrin levels.
SG induced a medium-term elevation of the insulin response and plasma gastrin levels without modification of the OGTT results. However, long-term depletion of the insulin response with elevated OGTT areas under the curve and plasma gastrin levels appeared after SG. Netazepide prevented the SG effect on these parameters. Gastrin tissue expression was greater in SG animals than in SG/netazepide-treated or control animals. The beta-cell mass was lower in the SG group than in the control or SG/netazepide group.
Gastrin stimulates a medium-term strong insulin response but also causes long-term beta-cell mass depletion and a loss of insulin response, the researchers concluded, and these effects are prevented by gastrin antagonists such as netazepide.
To access this paper, please click here
Preoperative comorbidities as a predictor of EBWL after bariatric surgery: a retrospective cohort study
A higher baseline BMI, diabetes mellitus, hypothyroidism, and undergoing laparoscopic sleeve gastrectomy may lead to lower %EBWL in the postoperative period after bariatric surgery, according to researchers at University of South Florida Morsani College of Medicine, Tampa, FL.
Reporting in Surgical Endoscopy, data from 440 patients found that those who had a higher baseline BMI (p<0.001), diabetes mellitus (p=0.026), hypothyroidism (p=0.046), and who had a laparoscopic sleeve gastrectomy rather than Roux-en-Y gastric bypass (p<0.001) had a smaller %EBWL in the first year after bariatric surgery as compared to patients without these comorbidities at the time of surgery. Controversially, patients with anxiety or depression (p=0.73) or obstructive sleep apnoea (p=0.075) did not have a statistically significant difference in %EBWL.
“This study provides new insight into which comorbidities may need tighter control in order to optimize weight loss outcomes after bariatric surgery,” the researchers concluded.
To access this paper, please click here
Analysis of influencing factors and construction of prediction model for postoperative nausea and vomiting in patients undergoing laparoscopic sleeve gastrectomy: a single-center retrospective cohort study
Postoperative nausea and vomiting (PONV) in patients undergoing LSG is related to gender, type of anaesthesia, duration of surgery and combination therapy with antiemetic drugs, researcher from Peking University Shenzhen Hospital, Shenzhen, Guangdong, China, report in BMC Anesthesiology.
The researchers explored the influencing factors of PONV in 144 patients undergoing LSG and constructed a nomogram prediction model based on these factors.
In total, 46 patients developed PONV, resulting in a PONV incidence rate of 40.4%. Multivariate logistic regression analysis revealed that female gender, the use of inhalation anaesthesia, and operation time ≥120 min were risk factors for PONV in LSG. Additionally, the use of more than two kinds of antiemetic drugs was identified as a protective factor. Based on these factors, a nomogram model was constructed.
The nomogram prediction model constructed in this study demonstrates high accuracy and discrimination in predicting the occurrence of PONV in patients undergoing LSG.
To access this paper, please click here
Pharmacotherapy for adults with overweight and obesity: a systematic review and network meta-analysis of randomised controlled trials
In adults with overweight and obesity, phentermine–topiramate and GLP-1 receptor agonists proved the best drugs in reducing weight; of the GLP-1 agonists, and semaglutide might be the most effective, an international team of researchers report in The Lancet.
This systematic review and network meta-analysis included 132 eligible trials (48,209) participants. All drugs lowered bodyweight compared with lifestyle modification alone; all subsequent numbers refer to comparisons with lifestyle modification. High to moderate certainty evidence established phentermine–topiramate as the most effective in lowering weight (odds ratio [OR] of ≥5% weight reduction 8·02, 95% CI 5·24 to 12·27; mean difference [MD] of percentage bodyweight change −7·98, 95% CI −9·27 to −6·69) followed by GLP-1 receptor agonists (OR 6·33, 95% CI 5·00 to 8·00; MD −5·79, 95% CI −6·34 to −5·25).
Naltrexone–bupropion, phentermine–topiramate, GLP-1 receptor agonists and orlistat were associated with increased adverse events leading to drug discontinuation. In a post-hoc analysis, semaglutide, a GLP-1 receptor agonist, showed substantially larger benefits than other drugs with a similar risk of adverse events as other drugs for both likelihood of weight loss of 5% or more and percentage bodyweight change.
To access this paper, please click here
Semaglutide in Patients with Obesity-Related Heart Failure and Type 2 Diabetes
An international team of researchers have for patients with obesity-related heart failure with preserved ejection fraction and type 2 diabetes, semaglutide led to larger reductions in heart failure–related symptoms and physical limitations and greater weight loss than placebo at one year.
Reporting in the New England Journal of Medicine, they randomly assigned 616 patients who had heart failure with preserved ejection fraction, a body-mass index (the weight in kilograms divided by the square of the height in meters) of 30 or more, and type 2 diabetes to receive once-weekly semaglutide (2.4 mg) or placebo for 52 weeks.
The mean change in the KCCQ-CSS was 13.7 points with semaglutide and 6.4 points with placebo (p<0.001), and the mean percentage change in body weight was −9.8% with semaglutide and −3.4% with placebo (p<0.001). The results for the confirmatory secondary end points favoured semaglutide over placebo (p=0.008]; win ratio for hierarchical composite end point, 1.58 [95% CI, 1.29 to 1.94; p<0.001]; and estimated treatment ratio for change in CRP level, 0.67 [95% CI, 0.55 to 0.80; p<0.001]). Serious adverse events were reported in 55 participants (17.7%) in the semaglutide group and 88 (28.8%) in the placebo group.
To access this paper, please click here
Semaglutide versus placebo in people with obesity-related heart failure with preserved ejection fraction: a pooled analysis of the STEP-HFpEF and STEP-HFpEF DM randomised trials
Semaglutide is superior to placebo in improving heart failure-related symptoms and physical limitations, and reducing bodyweight in participants with obesity-related heart failure with preserved ejection fraction, according to a an international team of researchers writing in The Lancet.
The STEP-HFpEF and STEP-HFpEF DM trials, the GLP-1 receptor agonist semaglutide improved symptoms, physical limitations, bodyweight, and exercise function in people with obesity-related heart failure with preserved ejection fraction. In this prespecified pooled analysis of the STEP-HFpEF and STEP-HFpEF DM trials, the researchers sought to provide a more definitive assessment of the effects of semaglutide across a range of outcomes and to test whether these effects were consistent across key patient subgroups.
In total, 529 people were randomly assigned in STEP-HFpEF and 616 were randomly assigned in STEP-HFpEF DM. Overall, 1145 were included in our pooled analysis, 573 in the semaglutide group and 572 in the placebo group.
They reported improvements in KCCQ-CSS and reductions in bodyweight between baseline and week 52 were significantly greater in the semaglutide group than in the placebo group (mean between-group difference for the change from baseline to week 52 in KCCQ-CSS 7.5 points (p<0·0001; mean between-group difference in bodyweight at week 52 −8·4% [−9·2 to −7·5]; p<0·0001). For the confirmatory secondary endpoints, 6-min walk distance (mean between-group difference at week 52 17.1 metres and the hierarchical composite endpoint were significantly improved, and CRP concentrations were significantly reduced, in the semaglutide group compared with the placebo group (p<0·0001 for all comparisons). 161 serious adverse events were reported in the semaglutide group compared with 301 in the placebo group.
The effects were largely consistent across patient demographic and clinical characteristics.
To access this paper, please click here