Smoking habits and progression of coronary and aortic artery calcification: A 5-year follow-up of community-dwelling Japanese men

Background and aims: To examine whether smoking habits, including smoking amount and cessation duration at baseline, are associated with atherosclerosis progression.

Methods: At baseline (2006-08, Japan), we obtained smoking status, amount of smoking and time since cessation for quitters in a community-based random sample of Japanese men initially aged 40-79 years and free of cardiovascular disease. Coronary artery calcification (CAC) and aortic artery calcification (AAC) as biomarker of atherosclerosis was quantified using Agatston's method at baseline and after 5 years of follow-up. We defined progression of CAC and AAC (yes/no) using modified criteria by Berry.

Results: A total of 781 participants was analyzed. Multivariable adjusted odds ratios (ORs) of CAC and AAC progression for current smokers were 1.73 (95% CI, 1.09-2.73) and 2.47 (1.38-4.44), respectively, as compared to never smokers. In dose-response analyses, we observed a graded positive relationship of smoking amount and CAC progression in current smokers (multivariable adjusted ORs: 1.23, 1.72, and 2.42 from the lowest to the highest tertile of pack-years). Among the former smokers, earlier quitters (≥10.7 years) had similar ORs of the progression of CAC and AAC to that of participants who had never smoked.

Conclusions: Compared with never smokers, current smokers especially those with greater pack-years at baseline had higher risk of atherosclerosis progression in community-dwelling Japanese men. Importantly, the residual adverse effect appears to be present for at least ten years after smoking cessation. The findings highlight the importance of early avoidance or minimizing smoking exposure for the prevention of atherosclerotic disease.