Effects of non-heavy smoking on high-density lipoprotein cholesterol in healthy Turkish young men.

ABSTRACT

OBJECTIVE: Decreased effects of smoking on serum high-density lipoprotein cholesterol (HDL-c) were demonstrated in subjects smoking more than 20 cigarettes a day. We aimed to evaluate the effects of non-heavy smoking (< or =20 cigarettes a day) on HDL-c in young, healthy men who are similar in terms of age, physical activity and diet. METHODS: A total of 1012 male students between 19 and 25 years old (21.4 +/- 1.5) in a military college who do not smoke or smoking < or =20 cigarettes a day were enrolled. Subjects who were consuming alcohol were excluded. Smoking levels (0 nonsmoker, 1 1-5 cigarettes, 2 6-10 cigarettes, 311-20 cigarettes a day) and duration were obtained by a questionnaire. Blood samples were taken after an over-night fasting. Blood pressure and anthropometric measurements were reported. RESULTS: HDL-c showed a stepwise decrease as the level of smoking increased (49 +/- 9 mg/dL in level 0, 47 +/- 7 mg/dL in level 1, 46 +/- 8 mg/dL in level 2, 45 +/- 7 mg/dL in level 3, p < 0.001). Total cholesterol, triglycerides and low-density cholesterol were not different among the smoking levels. Body mass index (BMI) and waist/hip ratio were found to be slightly decreased in smokers. In a multivariate regression model including smoking level, duration, BMI, systolic and diastolic blood pressures, smoking level was the only predictor of HDL-c (B = -1.407, p < 0.001). CONCLUSION: Smoking, even in relatively low levels, has a negative stepwise relationship with HDL-c in a homogeneous population of healthy young men in whom other major non-genetic factors that are known to affect HDL-c levels are identical.