Smoking, Smoking Cessation, and Measures of Subclinical Atherosclerosis in Multiple Vascular Beds in Japanese Men

BACKGROUND: Smoking is an overwhelming, but preventable, risk factor for cardiovascular diseases (CVD), although smoking prevalence remains high in developed and developing countries in East Asia.
METHODS AND RESULTS: In a population-based sample of 1019 Japanese men aged 40 to 79 years, without CVD, we examined cross-sectional associations of smoking status, cumulative pack-years, daily consumption, and time since cessation, with subclinical atherosclerosis at 4 anatomically distinct vascular beds, including coronary artery calcification, carotid intima-media thickness (CIMT) and plaque, aortic artery calcification (AoAC), and ankle-brachial index. Current, former, and never smoking were present in 32.3%, 50.0%, and 17.7%, respectively. Compared to never smokers, current smokers had significantly higher risks of subclinical atherosclerosis in all 4 circulations (eg, odds ratios for coronary artery calcification >0, 1.79 [95% CIs, 1.16-2.79]; CIMT >1.0 mm, 1.88 [1.02-3.47]; AoAC >0, 4.29 [2.30-7.97]; and ankle-brachial index <1.1, 1.78 [1.16-2.74]) and former smokers did in carotid and aortic circulations (CIMT >1.0 mm, 1.94 [1.13-3.34]; and AoAC >0, 2.55 [1.45-4.49]). Dose-response relationships of pack-years and daily consumption, particularly with CIMT, carotid plaque, AoAC, and ankle-brachial index, were observed among both current and former smokers, and even a small amount of pack-years or daily consumption among current smokers was associated with coronary artery calcification and AoAC, whereas time since cessation among former smokers was linearly associated with lower burdens of all atherosclerotic indices.
CONCLUSIONS: Cigarette smoking was strongly associated with subclinical atherosclerosis in multiple vascular beds in Japanese men, and these associations attenuated with time since cessation.