Inflammation
Bariatric surgery paradoxically raises Lp(a) by 66% while cutting oxidised-phospholipid markers, a prospective study of 59 patients (J Clin Lipidol 2021)
Original title: Effect of bariatric surgery on plasma levels of oxidised phospholipids, biomarkers of oxidised LDL and lipoprotein(a)
In a prospective study of 59 patients with severe obesity undergoing bariatric surgery (compared with 16 patients from a medical weight-management clinic), body mass index fell from a median 48 kg/m2 at baseline to 37 kg/m2 at 6 months and 33 kg/m2 at 12 months post-surgery. Oxidised phospholipids on apolipoprotein B (OxPL-apoB) significantly decreased at 12 months (5.0 to 3.8 nM, P=0.001), while Lp(a) significantly increased over the same period (10.2 to 16.9 mg/dL, P=0.002). IgG and IgM biomarkers of oxidised LDL also decreased significantly post-surgery, particularly at 12 months, while oxidised LDL itself remained unchanged. The findings show bariatric surgery paradoxically raises Lp(a) while reducing other oxidised-lipoprotein biomarkers, suggesting increased Lp(a) synthetic capacity alongside reduced oxidative stress after major weight loss.
Original abstract
Background: Obesity is associated with adverse cardiovascular outcomes and this is improved following bariatric surgery. Oxidised phospholipids (OxPL) are thought to reflect the pro-inflammatory effects of lipoprotein(a) [Lp(a)], and both are independent predictors of cardiovascular disease.
Objective: Our study sought to determine the impact of bariatric surgery on OxPL, biomarkers of oxidised LDL (OxLDL) and Lp(a).
Methods: This is a prospective, observational study of 59 patients with severe obesity undergoing bariatric surgery. Blood samples were obtained prior to surgery and at 6 and 12 months after. Sixteen patients attending the tertiary medical weight management clinic at the same centre were also recruited for comparison. Lipid and metabolic blood parameters, OxLDL, OxPL on apolipoprotein B-100 (OxPL-apoB), IgG and IgM autoantibodies to MDA-LDL, IgG and IgM apoB-immune complexes and Lp(a) were measured.
Results: Reduction in body mass index (BMI) was significant following bariatric surgery, from median 48 kg/m2 at baseline to 37 kg/m2 at 6 months and 33 kg/m2 at 12 months. OxPL-apoB levels decreased significantly at 12 months following surgery [5.0 (3.2-7.4) to 3.8 (3.0-5.5) nM, p = 0.001], while contrastingly, Lp(a) increased significantly [10.2 (3.8-31.9) to 16.9 (4.9-38.6) mg/dl, p = 0.002]. There were significant post-surgical decreases in IgG and IgM biomarkers, particularly at 12 months, while OxLDL remained unchanged.
Conclusions: Bariatric surgery results in a significant increase in Lp(a) but reductions in OxPL-apoB and other biomarkers of oxidised lipoproteins, suggesting increased synthetic capacity and reduced oxidative stress. These biomarkers might be clinically useful to monitor physiological effects of weight loss interventions.
Summary written by lp-a.org from the published abstract; figures as published. Page updated 18 August 2026. Methods.