Journal watch 17/9/2025

Welcome to our regular 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 SADISLEEVE outcomes, metabolic surgery versus GLP-1, impact of preoperative muscle and fat indices on post-sleeve gastrectomy weight loss, adverse outcomes in patients with hypothyroidism undergoing bariatric surgery and obesity treatment as a bridge to solid organ transplantation – MBS vs GLP-1s, and more (please note, log-in maybe required to access the full paper).

Efficacy and safety of single-anastomosis duodeno-ileal bypass with sleeve gastrectomy versus Roux-en-Y gastric bypass in France (SADISLEEVE): results of a randomised, open-label, superiority trial at 2 years of follow-up

Single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) showed superior weight loss compared with Roux-en-Y gastric bypass (RYGB) at two years, with a similar safety profile, according to researchers writing on behalf of the SADISLEEVE Collaborative Group.

Writing in The Lancet, the investigators conducted a multicentre randomised trial, with the hypothesis that SADI-S could be more effective than RYGB at 2-year follow-up. This multicentre, open-label, individually randomised superiority trial was conducted in France; patients were recruited from 22 bariatric institutions, mostly public academic hospitals. Participants were randomly assigned (1:1) to SADI-S or RYGB, stratified by centre, failure of sleeve gastrectomy, and presence of type 2 diabetes. The primary endpoint was percentage excess weight loss (%EWL) at 2 years.

A total of 381 patients were randomly assigned (intention-to-treat population) and included in the primary analysis (SADI-S: 190, RYGB: 191). At two years, the mean %EWL was statistically significantly higher in the SADI-S group compared with the RYGB group (–76·0% [SD 26·7] vs –68·1% [28·7], confirming the superiority of SADI-S (mean difference –6·72% [95% CI –12·64 to –0·80], p=0·026). The number of serious adverse events related to the surgical technique in the safety population, including all operated patients, was 40 in the SADI-S group including three anastomotic leaks and eight severe diarrhoea compared with 35 in the RYGB group including five internal hernia and five severe abdominal pain cases of which two required diagnostic laparoscopy.

To access this paper, please click here

Macrovascular and microvascular outcomes of metabolic surgery versus GLP-1 receptor agonists in patients with diabetes and obesity’, published in Nature Medicine.

People with obesity and type 2 diabetes who undergo metabolic and bariatric surgery (MBS) live longer and face fewer serious health problems, compared with those treated with GLP-1 receptor agonist medicines alone, according to a study by researchers from the Cleveland Clinic.

The M6 study (Macrovascular and Microvascular Morbidity and Mortality after Metabolic Surgery versus Medicines) followed 3,932 adults with diabetes and obesity who received care at Cleveland Clinic for up to 10 years. Among them, 1,657 underwent metabolic surgery (including gastric bypass or sleeve gastrectomy), while 2,275 were treated with GLP-1 medicines (including liraglutide, dulaglutide, exenatide, semaglutide, and tirzepatide).

At the end of the study, patients who had metabolic surgery had:

• 32% lower risk of death

• 35% lower risk of major heart problems (such as heart attack, heart failure, or stroke)

• 47% lower risk of serious kidney disease

• 54% lower risk of diabetes-related eye damage (retinopathy)

On average, people who had metabolic surgery lost 21.6% of their body weight over ten years, compared with 6.8% weight loss in people who took GLP-1 medicines. Haemoglobin A1c, a marker of average blood sugar, improved more with surgery (-0.86%) than with GLP-1 medicines (-0.23%). Patients in the surgery group also required fewer prescriptions for diabetes, blood pressure, and cholesterol.

The researchers noted that future studies should directly compare surgery with newer GLP-1 therapies, such as semaglutide and tirzepatide, to further guide treatment decisions.

To access this paper, please click here

Impact of Preoperative Muscle and Fat Indices on Post-Sleeve Gastrectomy Weight Loss

Preoperative body composition, particularly core muscle mass and subcutaneous fat distribution, is strongly associated with postoperative weight loss outcomes after sleeve gastrectomy (SG), according to researchers from the West China Hospital, Sichuan University, Chendu, China.

Reporting in Obesity Surgery, the study sought to investigate the relationship between preoperative body composition and postoperative weight loss outcomes in patients undergoing SG. Preoperative body composition was assessed using abdominal computed tomography (CT) and bioelectrical impedance analysis (BIA).

In a study of 315 individuals (63.5% female), CT analysis showed that males had significantly higher core muscle mass, including psoas major index (10.71 ± 2.35 vs. 7.12 ± 1.54 cm2/m2, p<0.001) and abdominal wall muscle index (58.19 ± 7.51 vs. 46.69 ± 5.83 cm2/m2, p=0.01), with no significant sex differences in fat distribution.

Multivariate regression identified age (OR = 0.925, 95% CI 0.861–0.993; p=0.032), wall muscle area (OR = 0.557, 0.349–0.888; p=0.014) and wall muscle index (OR = 4.214, 1.226–14.489; p=0.02) as independent predictors of weight loss. The combined model had better predictive accuracy for percent weight loss than body mass index alone (AUC = 0.840 vs ≤ 0.682; p<0.001).

CT-based assessments may offer valuable prognostic insight predict surgical outcomes and adjust interventions accordingly, the authors concluded.

To access this paper, please click here

Adverse outcomes in patients with hypothyroidism undergoing bariatric surgery: A retrospective study using TriNetX

Preexisting hypothyroidism in bariatric patients increases the risks of adverse outcomes. However, the risk of obesity-related outcomes is decreased in this population when compared to nonsurgical care, according to researchers from the University of Texas Medical Branch, Galveston, TX.

Writing in The Journal of Clinical Endocrinology & Metabolism, they evaluated the impact of preexisting hypothyroidism on adverse health outcomes following bariatric surgery.

Used data from the TriNetX Global Collaborative Network database, there were 5,700 patients in each cohort (46.7±12 years, 88% female). In the short term, patients with hypothyroidism exhibited higher risks of readmission (RR:1.25;CI:1.14-1.36), incisional hernia (RR:1.56;CI:1.12-2.18), and biliary diseases (RR:1.39;CI:1.05-1.86). In the long term, patients with hypothyroidism had higher risks of incident cerebrovascular events (HR:1.25;CI:1.00-1.55), diabetes (HR:1.39;CI:1.12-1.74), and dyslipidaemia (HR:1.20;CI:1.02-1.42). There were also higher risks of fall (HR:1.20;CI:1.02-1.40), osteoporosis (HR:1.30;CI:1.07-1.58), polyneuropathy (HR:1.34;CI:1.08-1.66), hypoglycemia (HR:1.51;CI:1.23-1.87), as well as iron (HR:1.17;CI:1.04-1.31) and vitamin B (HR:1.34;CI:1.20-1.49) deficiencies.

Hypothyroidism-associated risks of poor outcomes were higher in patients who underwent gastric bypass. Compared to the nonsurgical care, patients with hypothyroidism who underwent BS showed a lower risk of obesity-related outcomes but a higher risk of iron and vitamin B deficiencies, osteoporosis and hypoglycaemia.

To access this paper, please click here

Obesity treatment as a bridge to solid organ transplantation: A comparison of bariatric surgery to medical therapy

The current generation of weight loss medications produce a degree of weight loss comparable to bariatric surgery, supporting the hypothesis that medications could revolutionize the organ transplant process by providing a reasonable non-surgical weight loss option for individuals with obesity.

Researchers from the University of Oklahoma, School of Community Medicine, USA, writing in Obesity Pillars, compared peri-transplant weight loss in individuals treated with bariatric surgery alone, GLP-1 or GLP-1/GIP medication without surgical intervention, and GLP-1 or GLP-1/GIP medication with surgical intervention. Nineteen (N = 19) patients pursuing kidney transplant met inclusion criteria.

Individuals treated with tirzepatide (n = 9) demonstrated 8 % less weight loss than the surgical-intervention group, and 77.8 % (n = 7) met BMI cutoff for transplant after treatment. Among patients treated with semaglutide (n = 4), 50 % (n = 2) met BMI cutoff for transplant. In the bariatric-surgery only group, 66.7 % (n = 2) met the BMI cutoff for transplant. Among those who received both bariatric surgery and GLP-1 medication (n = 3), all met the BMI cutoff for transplant.

They concluded, that further study with a larger, prospective randomized trial is needed to fully evaluate the viability of utilising anti-obesity medications for this unique clinical indication.

To access this paper, please click here