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 a systematic mapping of upcoming randomised controlled trials (RCTs) in bariatric surgery, the outcomes of patient attendance at a perioperative group-based bariatric lifestyle program, three-year outcomes from SG and RYGB in patients with BMI>50, pregnancy outcomes after bariatric surgery and a study examining the long-term effect of bariatric surgery on lipogenesis in abdominal fat cells (please note, log-in maybe required to access the full paper).
The future of bariatric surgery research: A worldwide mapping of registered trials
Researchers at the European Hospital Georges Pompidou, Paris, France, writing in Obesity Reviews, who conducted a systematic mapping of upcoming randomised controlled trials (RCTs) in bariatric surgery (BS) have performed a systematic review of RCTs evaluating BS versus another surgical procedure or versus a medical control group.
They reported a total of 62 RCTs with 10,800 potential individuals to be included, planned Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy surgeries are the most common. The median number of patients planned to be enrolled is 78 and the mean follow-up time is 12 months in 55% of trials and four years or more in 23%.
The authors noted that the rising number of BS procedures around the world has been followed by a subsequent surge in BS research with an increase in outcomes such as obesity-related diseases, intermediate metabolic markers, quality of life and body composition.
The association between patient attendance to a perioperative group-based lifestyle program and weight loss after bariatric surgery
A multi-centre retrospective cohort study in the Netherlands has reported that patient attendance to a perioperative group-based bariatric lifestyle program (GBLP), is associated with a small but significant increase in postoperative weight loss up to three - but not four years after surgery.
Reporting in SOARD, they assessed the association between patient attendance to a perioperative GBLP and weight loss up to 48 months postoperatively. Patients who underwent primary laparoscopic Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) attended a GBLP in 2016 consisting of 18 sessions were included.
In total, 3,015 patients were included in the study, average TWL was 33% at 12 months after surgery, 33% at 24 months, 31% at 36 months and 31% at 48 months. Independent factors associated with a low attendance rate were younger age, male gender and SG. Independent factors negatively associated with %TWL were male gender, SG and diabetes mellitus.
A higher patient attendance to GBLP sessions is associated with a small but significant increase in postoperative weight loss up to three - but not four years after surgery.
Outcome of Sleeve Gastrectomy Versus Roux-en-Y Gastric Bypass for Patients with Super Obesity (Body Mass Index > 50 kg/m2)
Researchers from Germany have reported the outcomes from sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) on perioperative morbidity and remission of comorbidities at three years in patients with BMI>50 kg/m2.
Their retrospective multi-centre analysis included 2,939 patients (1,278 RYGB and 1,661 SG patients). Three years after surgery, the percent excess weight loss (%EWL) was 62.21% in RYGB and 55.87% in SG (p<0.001). The change in hypertension (p<0.001) and reflux (p<0.001) was significantly in favour of RYGB. The change in diabetes mellitus was not significant between the two groups.
Both procedures positively affected comorbidities, BMI, and %EWL in patients with super obesity 3 years after surgery. In some categories, RYGB was better than SG. Nevertheless, the decision between the two methods remains a matter of the surgeon’s experience and the patient's general condition.
Maternal Nutritional Status and Pregnancy Outcomes Post-bariatric Surgery
Investigators from the King Saud University, Riyadh, Saudi Arabia, have presented an overview obesity-related complications during pregnancy, and the benefits and risks of bariatric surgery on pregnancy outcomes and maternal nutrition status.
Writing in Obesity Surgery, they assessed the evidence that bariatric surgery reduces obesity-related complications during and after pregnancy, in addition to the evidence that bariatric surgery might be associated with adverse outcomes, such as low birth weight and small-for-gestational-age infants.
In addition, they noted several studies suggest pregnancy occurring less than a year post-bariatric surgery adversely affects pregnancy outcomes and causes micronutrients deficiency since the dramatic weight loss occurs in the first year.
Long-term improvement of adipocyte insulin action during body weight relapse after bariatric surgery: a longitudinal cohort study
Authors from Karolinska Institutet, Stockholm, Sweden, have investigated the long-term effect of bariatric surgery on lipogenesis in abdominal fat cells and whether surgical treatment could induce an epigenetic memory that would maintain improved lipogenesis in spite of body weight relapse.
They recruited 22 women who were examined before, two, five and ten years after bariatric surgery. Abdominal adipose tissue biopsies were obtained and fat cells were isolated and spontaneous and insulin stimulated glucose incorporation into lipids were assayed
They found that bariatric surgery was associated with improvement in adipocyte spontaneous and insulin stimulated lipogenesis, which was maintained despite some later weight regain (29 % of initial weight loss).
They concluded that bariatric surgery leads to long-term improvement of lipogenesis and insulin responsiveness in subcutaneous adipocytes in women in spite of some partial body weight regain post-operatively.