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 same-day discharge after sleeve gastrectomy, weight loss factors post-LSG, metabolic changes post-RYGB, internalised weight stigma and surgery, measures to reduce post-op bleeding and a Brazilian study effect of socioeconomic status on weight loss after surgery (please note, log-in maybe required to access the full paper).
Outcomes of Same-day Discharge Sleeve Gastrectomy and Roux-en-Y Gastric Bypass: A Systematic Review and Meta-analysis
A study by researchers at University of Illinois at Chicago, Chicago, IL, have reported that same-day discharge (SDD) after sleeve gastrectomy (SG) seems feasible and safe.
Writing in SOARD, the systematic review and meta-analysis sought to evaluate the safety and success of SDD following SG and Roux-en-Y gastric bypass (RYGB). SDD was defined as discharging the patient during the day of the bariatric operation, without an overnight stay. Primary outcomes were successful SDD, readmission and morbidity rates. Secondary endpoints included reoperation and mortality rates.
The researchers identified a total of 14 studies with 33,403 patients who had SDD SG (32,165) or RYGB (1,238). SDD success rate was 63-100% after SG and 88-98.1% after RYGB. Readmission rate ranged from 0.6-20.8% after SDD SG and 2.4-4% after SDD RYGB. Overall morbidity, reoperation and mortality were 1.1-10%, 0.3-2.1%, and 0-0.1% (PP: 0%), respectively, for SDD SG, and 2.5-4%, 1.9-2.5% and 0-0.9%, respectively, for SDD RYGB.
The researchers concluded that SDD RYGB seem promising, but the evidence is still limited to draw definitive conclusions.
A cross-sectional survey of patients attending follow-up visits after sleeve gastrectomy: Factors affecting weight loss
Pre-operative BMI, weight-loss regimens and childhood-onset as well as post-operative duration, can improve weight loss outcomes after laparoscopic sleeve gastrectomy (LSG), according to a paper published in Obesity Pillars by investigators from the Alexandria University, Egypt.
The study was designed to identify factors associated with improved or in-progress EWL among patients who had undergone LSG. In total, 100 adult surgical patients who had undergone LSG were selected from patients who attended follow-up in the study setting. Group A had an EWL% ≥50 and group B had an EWL <50. Body Mass Index classes were defined as 25–30kg/m2, >30–35kg/m2, >35–40 kg/m2 and >40 ≥ 45 kg/m2.
Six months post-op, 100% of the patients in group A had a BMI between 25 and 30 mg/m2, compared to 0% in group B. Patients in group EWL<50 (group B) who had pre-operatively BMI class ≥45 mg/m2, had a reduction in weight of 89.5% post-operatively, (n=2 still had a BMI >45 kg/m2 post operatively). In total, 63.9% of the patients in group B managed to get towards a BMI of 30–35 kg/m2 post-operatively.
The main factors associated with group B (less %EWL after six months) were found to be related to higher preoperative BMI, the onset of obesity started in childhood, less preoperative weight loss, longer postoperative duration towards weight reduction, and lower postoperative compliance to dietary instructions (p=0.0001, 0.048, 0.0001, 0.017 and 0.016, respectively).
The authors conclude that a focus on pre-operative BMI, weight-loss regimens and childhood-onset as well as post-operative duration, low responders, and compliance with clinical assessment could improve weight loss outcomes.
Changes in plasma free fatty acids in obese patients before and after bariatric surgery highlight alterations in lipid metabolism
UK researchers have highlighted the changes to non-esterified fatty acids (NEFAs) that take place following gastric bypass surgery in patients with severe obesity.
Writing in Scientific Reports, the investigators stated that the role of NEFAs in obesity-related morbidity is interesting as NEFAs constitute a reservoir of metabolic energy, are principal components of cell membranes and are precursors for signalling molecules. In this study they measure changes in circulating NEFA species in plasma samples taken from 25 individuals with obesity before and nine months after Roux-en-Y gastric bypass surgery.
The mean weight of the cohort reduced by 29.2% from 149.0±25.1kg pre-surgery to 105.5±19.8kg post-surgery and the BMI by 28.2% from 51.8±6.3kg/m2 pre-surgery to 37.2±5.4kg/m2. Mean glycated haemoglobin (HbA1c) reduced from 6.5±1.3 to 5.5±0.5%, consistent with the intervention leading to improved glycaemic control, particularly in those who were dysglycemic prior to surgery. Total and LDL cholesterol concentrations were markedly reduced following surgery. Concentrations of seven NEFAs were found to decrease nine months after surgery compared to pre-surgery levels: myristate, palmitoleate, palmitate, linoleate, oleate, stearate and arachidonate.
They report bariatric surgery led to increased lipogenesis and elongase activity and decreased stearoyl-CoA desaturase 1 activity.
Internalised Weight Stigma Mediates Relationships Between Perceived Weight Stigma and Psychosocial Correlates in Individuals Seeking Bariatric Surgery: a Cross-sectional Study
Researchers from the Australian Catholic University, Fitzroy, Australia, have reported that interventions addressing internalised weight stigma may be a useful tool for clinicians to reduce the negative correlates associated with weight stigma.
Reporting their findings in Obesity Surgery, they used data from a cross-sectional study with individuals seeking bariatric surgery (n=217; 73.6% female) from Melbourne, Australia. Participants completed a battery of self-report measures on weight stigma and biopsychosocial variables, prior to their procedures. Bias-corrected bootstrapped mediations were used to test the mediating role of internalised weight stigma. Significance thresholds were statistically corrected to reduce the risk of Type I error due to the large number of mediation tests conducted.
Controlling for BMI, internalised weight stigma mediated the relationship between perceived weight stigma and psychological quality of life, symptoms of depression and anxiety, stress, adverse coping behaviours, self-esteem, exercise avoidance, some disordered eating measures and body image subscales, but not physical quality of life or pain.
Bariatric surgery: to bleed or not to bleed? This is the question
Investigators from University of Foggia, Foggia, Italy, have reported that increasing mean arterial pressure (MAP) by 30% compared to preoperative and reducing the pneumoperitoneum pressure of CO2 to 8mmHg in the last 15 minutes of the operation led to a decrease in bleeding cases.
Reporting in BMC Surgery, they examined patients undergoing bariatric surgery from July 2017 to June 2020 (Group A) and those operated from July 2020 to June 2022 (Group B). From July 2020, they implemented intraoperative measures to prevent postoperative bleeding, increasing mean arterial pressure (MAP) by 30% compared to preoperative and reducing the pneumoperitoneal pressure of CO2 to 8mmHg in the last 15 minutes of the operation.
In total, 200 patients divided into the two described groups. The mean age of Group A was 44±8.49 and 43.73±9.28. The mean preoperative BMI is 45.6 kg/m2±6.71 for Group A and 48.9±7.15 kg/m2 for Group B. Group A recorded a mean MAP of 83.06±18.58 mmHg and group B a value of 111.88±12.46 mmHg (p< 0.05).
There were nine cases of bleeding in group A, most of them being treated with medical therapy and transfusions; only 1 hemodynamically unstable patient underwent re-laparoscopy. They reported only two cases of bleeding in group B, one of which required blood transfusions.