Dose-Response Association between Smoking Cessation and Arterial Stiffness: The Cardiovascular and Metabolic Diseases Etiology Research Center (CMERC) Cohort

BACKGROUND AND OBJECTIVES: Cigarette smoking has been reported to be associated with arterial stiffness. However, the clinical relevance of smoking cessation on arterial stiffness is debatable. Thus, we evaluated whether smoking cessation is associated with arterial stiffness. METHODS: A total of 1,169 male participants aged 30-64 years with absence of cardiovascular diseases in 2013-2017 were selected from the Cardiovascular and Metabolic Disease Etiology Research Center cohort study. The subjects were classified into the following 5 groups based on self-reporting: non-smokers, former smokers (<1, 1 to <10, and ≥10, years after cessation), and current smokers. Arterial stiffness was assessed using the augmentation index (AIx). The radial artery AIx was obtained from the peripheral artery waveform. The association was explored cross-sectionally. RESULTS: The AIx of former smokers did not differ from that of non-smokers (p=0.089). However, after former smokers were stratified by duration of smoking cessation, we noted a linear trend according to the smoking status (p<0.001). Men who quit smoking <1 year ago showed an elevated AIx (β=3.94, standard error=1.54, p=0.011) as much as ones of current smokers (β=4.39, standard error=0.74, p<0.001), while those who quit more than a decade ago showed an AIx similar to that of non-smokers (β=0.35, standard error=0.82, p=0.670) after controlling covariates. CONCLUSIONS: A dose-response association between smoking cessation and AIx was revealed, which implies the possibility of a reversible effect of smoking cessation on arterial stiffness. Therefore, our findings may motivate current smokers to modify their smoking habits to delay or reverse disease progression.