Effects of Smoking on Serum Lipids: Relationship between Responses of Serum Lipids and Leukocyte Counts to Cigarette Smoking

to be about 15%. Subjects were advised to have blood tests in the morning after a 12 h or longer fast. LDL cholesterol was estimated using the equation of Friedewald, Levy, and Frederickson 16 in subjects with TG below 400 mg/dl ( n =9806). Background It has been found that the response of leukocyte counts to cigarette smoking differs among individuals, but there has been no study on individual diversity in the response of serum lipids to smoking. Methods A cross-sectional study of 9953 men not taking medication for diabetes, hypertension, dyslipide-mia, or hyperuricemia was conducted, and for it, information regarding current medication and lifestyle habits was obtained through a self-reported questionnaire. Results Non-smokers, ex-smokers, and persons currently smoking 1−19 and 20 or more cigarettes per day accounted for 33.7, 26.4, 13.9 and 25.9% of all subjects, respectively. We compared mean levels of serum lipids among them after adjusting for age, BMI, alcohol consumption, and frequency of exercise. Analyses of the results for all subjects revealed that smoking was associated with higher levels of TG, and lower levels of HDL and LDL cholesterol. When only subjects with leukocyte counts in the highest quartile ( ≧ 6.8 × 10 9 cells/l) were analyzed, smoking was only observed to affect TG and HDL cholesterol. However, in the case of subjects with leukocyte counts in the lowest quartile (<4.9 × 10 9 cells/l) smoking was seen to only affect HDL and LDL cholesterol, and the decrease in HDL cholesterol due to smoking appeared to be much smaller than that in subjects with leukocyte counts in the highest quartile. Conclusion These results suggest a relationship between the responses of serum lipids and leukocyte counts to smoking. ( Ningen Dock 2011 ; 25 : 27 30)