BACKGROUND: Obesity is a chronic disease associated with other associated medical problems, including atherogenic dyslipidemia. Metabolic bariatric surgery (MBS) has been shown to reduce long-term cardiovascular risk (CVR). Anti-ApoA-1 antibodies (AAA1) are independently associated with cardiovascular disease, which remains a major cause of death in individuals with obesity. This study aimed to determine the effect of MBS on anti-ApoA-1 antibodies. We also looked for changes in lipid parameters, insulin resistance, inflammatory profile, and percentage of total weight loss (%TWL). METHODS: We assessed 72 patients before surgery and 12 months postoperatively. Clinical history and measurements of body mass index (BMI), lipid profile (including non-HDL cholesterol, TG/HDL-C ratio, TG-Gly index, total cholesterol to HDL ratio), AAA1, CRP, fasting plasma glucose (FPG), HbA1c, and HOMA-IR were measured/calculated at each point. RESULTS: MBS significantly improved BMI, %TWL, lipids, anti-ApoA-1 antibodies, CRP, HBA1c, FBG, and HOMA-IR. Baseline AAA1 antibodies were positive in 38.9% and were associated with higher CRP levels, total cholesterol, LDL-C, total cholesterol to HDL ratio, and non-HDL cholesterol. One year after MBS, there was a significant reduction in anti-ApoA-1 antibodies (p <
0.001). Furthermore, there was a significant postoperative correlation between anti-ApoA-1 antibodies with total cholesterol. Also, there were significant correlations between HBA1C (%), TG-Gly index, and HOMA-IR. CONCLUSIONS: Antibodies to apolipoprotein A-1 levels are significantly reduced following MBS. Furthermore, there was a notable improvement in the HBA1C, CRP, and lipid profile.