Background: Bariatric surgery improves lipid profile. A still unanswered question is whether this improvement is merely weight-dependent or also results from factors inherent to specificities of the bariatric procedure. We aimed to study lipid profile 1 year after bariatric surgery and compare its changes between the different procedures in patients matched for initial weight and weight loss.
Methods: We retrospectively analysed patients submitted to Roux-en-Y gastric bypass (RYGB), adjustable gastric banding (AGB) or sleeve gastrectomy (SG) between 2010 and 2013. Patients were matched for age (±5 years), sex, pre-surgery body mass index (BMI) (±2 Kg/m(2)) and excess weight loss (EWL) (±5%). Baseline and 1-year lipid profile, its variation and percentage of variation was compared between surgeries.
Results: We analysed 229 patients: 72 pairs RYGB-AGB, 47 pairs RYGB-SG and 33 pairs AGB-SG. The median age was 41 (35-52) years and 11.8% were male. Pre-operative BMI was 44.0 ± 4.6 and 32.1 ± 4.4 Kg/m(2) at 1 year. EWL at 1 year was 64.2 ± 18.9%. There were no differences in baseline lipid profile between patients submitted to different types of bariatric surgery. At 1 year, high-density lipoprotein cholesterol (HDL) and triglycerides (TG) improved similarly with all surgeries. Total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) at 1 year decreased significantly more in patients submitted to RYGB than in weight-matched patients undergoing AGB or SG.
Conclusions: RYGB is the only bariatric surgery that reduces TC and LDL in age-, sex-, BMI- and EWL-matched patients. All three procedures improved TG and HDL similarly when the confounding effect of weight loss is eliminated.
Keywords: Adjustable gastric banding; Bariatric surgery; Lipid profile; Matched study; Roux-en-Y gastric bypass; Sleeve gastrectomy.