Detection of Vascular Inflammation and Oxidative Stress by Cotinine in Smokers: Measured Through Interleukin-6 and Superoxide Dismutase

Purpose: Smoking is a significant risk factor in developing cardiovascular disease pathogenesis through oxidative stress and inflammation mechanisms. This study used cotinine as a biomarker of nicotine exposure levels in the body, which was associated with levels of Interleukin-6 (IL-6) and Superoxide Dismutase (SOD) as markers of oxidative stress and vascular inflammation. The research aimed to analyze the effect of cotinine levels on the expression of IL-6 and SOD. Methods: This study used a cross-sectional design on 200 subjects, consisting 100 smokers and 100 non-smokers. Cotinine levels, IL-6 expression, and SOD were measured from the blood serum of each subject using the Enzyme-Linked Immunosorbent Assay (ELISA) method. Then the data were analyzed using Generalized Structured Component Analysis (GSCA). Results: There was a significant effect of cotinine levels on the reduction of SOD mediated by IL-6 (CR = 4.006). Cotinine levels also increased IL-6 mediated by SOD (CR = 4.292). The structural model shows that higher cotinine levels will increase IL-6 expression, and conversely, SOD expression will decrease. Conclusion: High cotinine levels cause an increase in the inflammatory process and oxidative stress in the vasculature of smokers, which is characterized by high IL-6 expression and low SOD expression. Keywords: cotinine, IL-6, SOD, oxidative stress, cardiovascular disease, smoking