Short-Term Changes in TNF-Alpha, IL-6 and Adiponectin Following Bariatric Surgery in Caucasian Obese Adults: An Observational Case-Control Study.

Abstract

Background and Objectives: Overweight and obesity are well-known conditions that negatively impact the health and lifestyle of an individual. Bariatric surgery is one of the most efficient weight loss techniques. Besides the main effect on the bodyweight, improvement in the levels of inflammatory biomarkers, such as interleukin 6 (IL-6), tumor necrosis factor alpha (TNFalfa), and others, has been observed. The purpose of this study was to establish the correlations between obesity-linked chronic systemic inflammation (estimated with inflammatory cytokine levels) and the weight loss process after metabolic surgery. Materials and Methods: An observational cohort study included two categories: the patients with obesity-bariatric group and the patients without obesity-control group. The study was performed between 1 February 2021 and 1 March 2023. Baseline characteristics, anthropometrics, biochemical assessment and inflammatory biomarkers were measured both before surgery and one year after the procedure, in the case of the bariatric group. The control group was assessed in the same period as the pre-surgery bariatric group. The bariatric group underwent two types of bariatric procedures: the majority underwent laparoscopic sleeve gastrectomy whereas a select few underwent one anastomosis laparoscopic gastric bypass. Results: We performed a prospective study comprising 55 Caucasian patients-from which 33 patients had morbid obesity, a mean age of 41.76 ± 10.78 and a mean BMI of 43.34± 7.51 kg/m2. The preoperative levels of IL-6 were positively correlated with waist circumference (r = 0.354, p = 0.043), weight (r = 0.549, p = 0.001) and BMI (r = 0.520, p = 0.002). After applying the Kruskal-Wallis test and Dunn's test, significant differences for IL-6 (p = 0.010) and adiponectin (p = 0.024) were obtained for values recorded pre- and post-surgery. No correlation was found between adiponectin, IL-6, TNF- α levels and anthropometric indices after surgery. Our study showed that bariatric surgery significantly changes the values of inflammatory cytokines one year after surgery. Nevertheless, we did not find significant correlations between the baseline values of these inflammatory markers and the weight loss process after surgery at a short-term (one-year) follow-up. Conclusions: Our study demonstrated that bariatric surgery significantly changes the level of inflammatory cytokines one year after operation. We demonstrate that preoperative levels of IL-6 are positively correlated with age, WC, and BMI.