0008Cardiovascular Mortality by Smoking Status Across Levels of Arterial Stiffness: Findings from NHANES 2005–2016

Objective To examine whether the association between smoking status and cardiovascular (CV) mortality differs by arterial stiffness, assessed by pulse pressure index (PPI), among U.S. adults without baseline cardiovascular disease (CVD). Methods We analyzed 16,605 adults aged ≥40 without baseline CVD from NHANES 2005– 2016, with mortality follow-up through December 2019. PPI was calculated as (systolic − diastolic blood pressure)/systolic blood pressure and split at the cohort median into low and high groups. Smoking was classified as never, former, or current, creating six joint PPI–smoking groups. Cox models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for CV mortality. Restricted cubic splines assessed the continuous PPI–mortality relationship by smoking status. Results Over median follow-up of 8.4 years, 518 CV deaths (3.1%) occurred. Compared with never smokers in the same PPI group, former smokers with low PPI had similar CV mortality (HR 0.86, 95% CI 0.56–1.33), while current smokers with low PPI had over twice the risk (HR 2.51, 95% CI 1.65–3.81). In the high PPI group, both former and current smokers had higher CV mortality than never smokers. Spline analyses showed that CV mortality rose steeply with increasing PPI among current smokers, moderately among former smokers, and remained flat among never smokers. Conclusion Arterial stiffness modified the relationship between smoking and CV mortality. Former smokers had favorable CV outcomes only when PPI was low, suggesting the benefit of cessation is greatest before significant vascular aging develops. Is this an encore abstract? No