Does preoperative weight loss in a specialist medical weight management centre influence postoperative weight loss after bariatric surgery?

Summary: Weight loss of 5%–10% is advised in medical weight management (MWM) programmes prior to bariatric surgery but it remains to be established whether it influences postoperative weight loss outcomes. We studied postoperative percent total weight loss (%TWL) in 168 patients categorized by preoperative referral weight loss <5% or ≥5% in a UK NHS bariatric centre. Eighty‐six (51.2%) patients achieved sustained referral weight loss <5% (Group A) and 82 (48.8%) ≥5% (Group B). Overall postoperative %TWL in Group A compared with Group B was 30.0% versus 28.3% (p = .30) at 12 months and 32.5% versus 29.6% (p = .20) at 24 months. There were no significant differences in postoperative %TWL at 12 and 24 months when categorized by procedure (gastric bypass, n = 106; or sleeve gastrectomy, n = 62), age or sex. Preoperative weight loss during intensive specialist MWM did not influence postoperative weight loss up to 24 months with gastric bypass or sleeve gastrectomy

Triacylglycerol Fatty Acid Composition in Diet-Induced Weight Loss in Subjects with Abnormal Glucose Metabolism – the GENOBIN Study

BACKGROUND: The effect of weight loss on different plasma lipid subclasses at the molecular level is unknown. The aim of this study was to examine whether a diet-induced weight reduction result in changes in the extended plasma lipid profiles (lipidome) in subjects with features of metabolic syndrome in a 33-week intervention. METHODOLOGY/PRINCIPAL FINDINGS: Plasma samples of 9 subjects in the weight reduction group and 10 subjects in the control group were analyzed using mass spectrometry based lipidomic and fatty acid analyses. Body weight decreased in the weight reduction group by 7.8+/-2.9% (p<0.01). Most of the serum triacylglycerols and phosphatidylcholines were reduced. The decrease in triacylglycerols affected predominantly the saturated short chain fatty acids. This decrease of saturated short chain fatty acid containing triacylglycerols correlated with the increase of insulin sensitivity. However, levels of several longer chain fatty acids, including arachidonic and docosahexanoic acid, were not affected by weight loss. Levels of other lipids known to be associated with obesity such as sphingolipids and lysophosphatidylcholines were not altered by weight reduction. CONCLUSIONS/SIGNIFICANCE: Diet-induced weight loss caused significant changes in global lipid profiles in subjects with abnormal glucose metabolism. The observed changes may affect insulin sensitivity and glucose metabolism in these subjects. TRIAL REGISTRATION: ClinicalTrials.gov NCT00621205