Effects of cigarette smoking on blood lipids in Korean men: Cardiovascular and Metabolic Diseases Etiology Research Center cohort

Background/Aims: Cigarette smoking and abnormal blood lipids are major risk factors for cardiovascular disease. The results of previous studies on the relationship between cigarette smoking and dyslipidemia are controversial. In the present study, we investigated the independent association between cigarette smoking and blood lipid levels in a male Korean population. Methods: A total of 1,932 men aged from 30 to 64 years old participated in the Cardiovascular and Metabolic Diseases Etiology Research Center cohort study. Smoking history was obtained by in-person interviews. In all regression models, measurements of triglyceride levels were log-transformed. Results: Triglyceride levels were higher in current smokers than in never-smokers (median: 149 mg/dL vs. 115 mg/dL, p < 0.001) even after adjusting age, body mass index, alcohol intake, systolic blood pressure, fasting glucose, physical activity, and nutrition intake (beta = 0.14, p < 0.001). We further divided people into heavy and light smokers using 20 pack-years as the cut-off. Higher triglyceride were found in current heavy smokers (beta= 0.18, p < 0.001), current light smokers (beta = 0.13, p < 0.001), as well as in past heavy smokers (beta= 0.08, p = 0.037), as compared to never-smokers. Moreover, significantly lower high-density lipoprotein cholesterol (HDL-C) were observed in current heavy smokers (beta = -2.27 mg/dL, p = 0.009). Conclusions: Cigarette smoking is associated with higher triglyceride in Korean men, with the most dramatic effect seen in current smokers with a smoking history of more than 20 pack-years. HDL-C were also lower in current smokers with more than 20 pack-years.