Abstract P132: Time Since Smoking Cessation and Pulse Wave Velocity: The Atherosclerosis Risk in Communities (ARIC) Study
Cigarette smoking is a preventable cause of cardiovascular disease and is associated with arterial stiffening among young adults. While smoking cessation lowers the risk of cardiovascular morbidity and mortality, evidence for a relationship between time since smoking cessation and arterial stiffness is limited in older adults. We assessed the association of smoking status and time since smoking cessation with arterial stiffness, measured by carotid-femoral (cfPWV) and brachial-ankle (baPWV) pulse wave velocity, conditional on intensity and duration of exposure to smoking (pack-years). Analyses included 1,996 men and 2,767 women aged 67 to 90 years examined in the ARIC study in 2011-2013. Smoking status was ascertained at all five ARIC examinations and during annual telephone interviews. Information on age at initiation of smoking, smoking intensity and duration were also collected. Pack-years were calculated as the product of the average number of cigarettes smoked per day and years smoked divided by 20. Two measures of baPWV and cfPWV were obtained then averaged. Multivariable linear regression was used to estimate the association between smoking status and time since smoking cessation with PWV by gender, adjusted for age, hypertension, body mass index (BMI), and heart rate. Estimates of the association between smoking cessation and PWV were further adjusted for pack-years. Among women, former smokers and current smokers had a lower baPWV when compared to never smokers [β = -40.9 (95% confidence interval (CI): -64.2, -17.6) and β = -119.7 (95%CI: -168.7, -70.7), respectively]. Similar patterns were observed for cfPWV; however, the relationship was only significant among former smokers [β = -25.3 (95%CI: -48.0, -2.5)]. Association of smoking status and PWV was not significant in men. Among men who were former smokers there was a negative and significant association between smoking cessation and cfPWV [β = -1.4 (-2.7, -0.4)]; however, this same relationship was not observed for baPWV. BMI modified the association between smoking cessation and PWV in women. Time since smoking cessation was positively associated with PWV in women with a BMI <25 kg/m 2 [baPWV: β = 3.8 (95%CI: 1.2, 6.5); cfPWV: β = 2.5 (0.3, 4.7)], but not in women with a BMI ≥25 kg/m 2 . In these cross-sectional analyses, ever smokers had lower PWV compared to never smokers among older women, but not among older men. Greater time since smoking cessation was positively associated with arterial stiffness among normal or underweight women, but not among women who were overweight or obese, or among men. Accounting for cumulative exposure to smoking over the life course, gender-specific and arterial segment-specific patterns were observed in the association between time since smoking cessation and arterial stiffness measured in community-dwelling older adults, as well as a modification of these associations by excess weight among women.