Changes in Lipid Profile of Obese Patients Following Contemporary Bariatric Surgery: A Meta-Analysis

Abstract

Background Although metabolic surgery was originally performed to treat hypercholesterolemia, the effects of contemporary bariatric surgery on serum lipids have not been systematically characterized. Methods and Results MEDLINE, EMBASE and Cochrane databases were searched for studies with ≥20 obese adults undergoing bariatric surgery [Roux-en-Y Gastric Bypass (RYGBP), Adjustable Gastric Banding, Bilio-Pancreatic Diversion (BPD), or Sleeve Gastrectomy]. The primary outcome was change in lipids from baseline to one-year after surgery. The search yielded 178 studies with 25,189 subjects (pre-operative BMI 45.5±4.8kg/m2) and 47,779 patient-years of follow-up. In patients undergoing any bariatric surgery, compared to baseline, there were significant reductions in total cholesterol (TC; -28.5mg/dL), low density lipoprotein cholesterol (LDL-C; -22.0mg/dL), triglycerides (-61.6mg/dL) and a significant increase in high density lipoprotein cholesterol (6.9mg/dL) at one year (P<0.00001 for all). The magnitude of this change was significantly greater than that seen in non-surgical control patients (eg LDL-C; -22.0mg/dL vs -4.3mg/dL). When assessed separately, the magnitude of changes varied greatly by surgical type (Pinteraction<0.00001; eg LDL-C: BPD -42.5mg/dL, RYGBP -24.7mg/dL, Adjustable Gastric Banding -8.8mg/dL, Sleeve Gastrectomy -7.9mg/dL). In the cases of Adjustable Gastric Banding (TC and LDL-C) and Sleeve Gastrectomy (LDL-C), the response at one year following surgery was not significantly different from non-surgical control patients. Conclusions Contemporary bariatric surgical techniques produce significant improvements in serum lipids, but changes vary widely, likely due to anatomic alterations unique to each procedure. These differences may be relevant in deciding the most appropriate technique for a given patient.

Laparoscopic sleeve gastrectomy: a study of efficiency in treatment of metabolic syndrome components, comorbidities and influence on certain biochemical markers.

“…The LSG procedure appeared to have a reductive effect in medium serum levels of atherosclerosis-promoting lipid factions (TG, LDL, TC), wherein the observed serum level of the protective HDL fraction rose during the follow-up. Improvements in lipid metabolism caused by bariatric procedures are known in the scientific literature, but each operation technique induce changes with different intensity; thus an appropriate procedure should be selected for dyslipidemia severity in the patient [33,34]. During the follow-up we also observed pleiotropic improvements in many other obesity-related comorbidities, like other authors assessing patients after bariatric surgery [35,36].…”

Practical Recommendations of the Obesity Management Task Force of the European Association for the Study of Obesity for the Post-Bariatric Surgery Medical Management

“…Apparently only RYGB, but not gastric banding [68] or gastric sleeve gastrectomy [69], is associated with reduced absorption of cholesterol. A recent systematic review and meta-analysis demonstrated that LDL-cholesterol was reduced significantly after gastric bypass (0.64 mmol/l) and biliopancreatic diversion (1.17 mmol/l), while the LDL-lowering effects of gastric banding (0.23 mmol/l) and sleeve gastrectomy (0.20 mmol/l) were small or non-significant [70]. To conclude, the beneficial effect of bariatric surgery on triglyceride and HDL-cholesterol levels seems to be weight loss-dependent while the improvement in LDL-cholesterol levels after gastric bypass surgery is at least partly weight loss-independent.…”

Long-term effects of bariatric surgery on cardiovascular risk factors in Singapore

“…(11) A meta-analysis of the impact of bariatric surgery on lipid profile also did not find that TC improved significantly. (9) One possible explanation is that outcomes were procedure-related. The majority of our subjects underwent sleeve gastrectomy, but Roux-En-Y gastric bypass (RYGB) has been shown to be more effective in lowering lipid level.…”

“…However, most of the studies are based on followup data of two years' duration or less. (9) Both the intermediate and long-term impact of bariatric surgery on hyperlipidaemia and its comorbidities are limited, especially in the Asian population. (10) We aimed to evaluate the impact of bariatric surgery on lipid profile, glycaemic control and weight loss at five-years' follow-up.…”