Early effects of cigarette smoke on adolescent endothelial functions: a novel endocan/cotinine ratio approach

Abstract Objectives This study aimed to investigate the early effects of cigarette smoke exposure on endothelial function in healthy adolescents by analyzing blood endocan levels and urinary cotinine concentrations. A novel endocan/cotinine ratio was proposed to enhance the assessment of endothelial response to tobacco exposure. Methods In this cross-sectional case-control study, 88 adolescents aged 13–18 years were recruited from Istanbul University between January and August 2021. Participants were divided into two groups: exposed (n=44) and non-exposed (n=44) to cigarette smoke. Blood endocan and urine cotinine levels were measured using ELISA. Statistical analysis included the Mann-Whitney U test and Spearman’s correlation. Results Among the exposed participants, 11.4 % (n=5) were active smokers and 88.6 % (n=39) were passive smokers. Systolic blood pressure was significantly higher in the exposed group (p=0.03). Although endocan levels did not differ significantly between groups (p=0.74), median values were higher in the exposed group (1847.5 pg/mL, range: 14.79–3,121.63) compared to controls (1806.2 pg/mL, range: 116.83–4,618.90). Urinary cotinine levels were markedly elevated in the exposed group (p