Smoking Status and Cardiovascular Mortality Differ by Arterial Stiffness Level Assessed by Pulse Pressure Index

ObjectiveTo 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). MethodsUsing data from the National Health and Nutrition Examination Survey (NHANES) 2005-2016, we analyzed 16,605 adults aged 40-79 years without baseline CVD, with mortality follow-up through December 31, 2019. PPI was calculated as (systolic blood pressure [SBP] - diastolic blood pressure [DBP])/SBP and split at the cohort median (0.415) as low versus high. Smoking status was classified as never, former, or current, yielding six joint PPI-smoking groups. Cox models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for CV mortality, adjusting for demographics and cardiometabolic risk factors. ResultsOver a median follow-up of 8.4 years, 518 CV deaths (3.1%) occurred. Among individuals with low PPI, former smokers had CV mortality comparable to never smokers (HR 0.86, 95% CI 0.56-1.33), whereas current smokers remained at elevated risk (HR 2.51, 95% CI 1.65-3.81). This pattern was not observed in the high PPI stratum, where both former and current smokers had significantly higher CV mortality than never smokers. ConclusionFormer smokers with low PPI had CV mortality similar to never smokers, whereas former smokers with high PPI remained at elevated risk. These findings suggest that the CV benefit of smoking cessation may be greatest when arterial stiffness is minimal, supporting early cessation before substantial vascular aging occurs.