Abstract
Background: Smoking cessation is associated with unfavorable weight gain, and HDL cholesterol (HDL-C) favorably increases. However, the long term effects of changes in smoking habit on waist circumference (WC), body weight (BW) and HDL-C are not clear. The purpose of this study was to examine the effects of changes in smoking habits on HDL-C and BW over 4 years.
Methods: Subjects were 18,289 men (20-64 years of age) who had annual medical check-ups consecutively for 4 years from April 1 2008 to March 31, 2011. They were divided into 4 groups based on the smoking habits change from the 1st year compared to the next 2 years: “non-smoking”, “smoking cessation”, “smoking” and “smoking initiation”. The changes in WC, BW and HDL-C over 4 years were analyzed using the analysis of variance.
Results: From 2008 to 2009, WC and BW significantly increased in the smoking cessation group (+1.30 cm,+0.87 kg) and BW decreased (-0.54 kg), but WC did not change significantly in the smoking initiation group.
HDL-C also increased in the non-smoking group (+2.9 mg/dL) but did not change significantly in the smoking initiation group.
Over 4 years, the increase in WC, BW and HDL-C was largest in the smoking cessation group (+1.43 cm,+1.57 kg and +4.7 mg/dL, respectively). In the smoking and non-smoking groups, WC, BW and HDL-C slightly increased but no significant change was observed in the smoking initiation group. The effects of changes in smoking habits on WC, BW and HDL-C were largest during the first year and then gradually declined during the next 3 years.
Conclusion: The usual HDL-C reduction accompanying weight gain was not observed after the cessation of smoking. In the smoking cessation group, WC and weight gain continued over the 4 years, but HDL-C also improved. It is suggested that continuing smoking cessation for several years would contribute to the improvement of the atherosclerotic risk factor.
