Effect of bariatric surgery in the evolution of oxidative stress depending on the presence of atheroma in patients with morbid obesity.

Background: Morbid obesity is associated with accelerated atherosclerosis, a chronic vascular disease related to oxidative stress (OS) and endothelial dysfunction. Objectives: We aimed to evaluate the effect of bariatric surgery (BS) on oxidative stress as a cardiovascular risk factor in patients with and without atheromatous plaques. Setting: Arnau de Vilanova University Hospital and University of Barcelona. Methods: Plasma samples from 66 patients with morbid obesity were obtained before BS and 6 and 12 months after. Patients were divided into 2 groups based on the presence of atheromatous plaques (detected by ultrasonography). OS parameters were measured by enzyme-linked immunosorbent assay. Results: Patients with morbid obesity had OS independently of the presence of an atheroma, but oxidized low-density lipoprotein levels were higher in patients with plaques throughout the study (P = .0430). After surgery, oxidized low-density lipoprotein and malondialdehyde levels decreased significantly (P < .0001 in both cases). At the beginning of the study, antioxidant enzyme levels were the same between the groups. After surgery, paraoxonase 1 levels were increased (P < .0001) in the group without plaque, being significantly higher (P = .0147). Superoxide dismutase 2 levels were only decreased in patients without plaque (P < .0010), while catalase activity was higher in patients with plaque. Conclusions: Morbid obesity may lead to chronic OS, which increases predisposition to atherogenesis. BS improves the antioxidant profile and reduces OS and co-morbidities in both groups. However, the benefits are greater for patients without plaque. Therefore, BS may prevent atheroma formation and also could prevent plaque rupture by decreasing OS. (C) 2020 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.