Abstract 289: Peripheral Arterial Disease and Vulnerability to Cardiovascular Events: Data from the Heart and Soul Study

Abstract

Objectives: Among patients with coronary artery disease (CAD), those with comorbid peripheral arterial disease (PAD) have a greater vulnerability to cardiovascular (CV) events than those with CAD alone. It is unclear why the presence of PAD predisposes patients with CAD to adverse CV outcomes. In a prospective cohort study of patients with CAD, we evaluated potential mechanisms that might explain the adverse CV outcomes associated with PAD. Methods: We evaluated 1020 patients with stable CAD who were recruited from 2000-2002 and followed for an average of 7.2 ± 2.6 years. Incident PAD events were adjudicated based on physician diagnosis, radiological imaging and/or need for PAD surgery. We used Cox proportional hazards models to evaluate the association between development of PAD events (entered as a time-dependent covariate) and subsequent risk of cardiovascular (CV) events (myocardial infarction, congestive heart failure, cerebrovascular event, revascularization) or death based on detailed review of medical records. Models were adjusted for traditional cardiovascular risk factors (age, race, sex, diabetes, hypertension, hypercholesterolemia, kidney function, inflammation) and self-reported history of PAD at baseline. Results: Among the 1020 patients, 67 patients developed incident PAD events during the follow-up period. Patients who developed PAD events had a higher risk of subsequent CV events and death compared to those who did not develop PAD (Figure). After adjustment for traditional cardiovascular risk factors and self-reported history of PAD, development of PAD events remained associated with an 84% increased risk of subsequent cardiovascular events [adjusted HR 1.84, 95% CI 1.15, 2.96, p=0.01] and an 89% increased risk of death [adjusted HR 1.89, 95% CI 1.30-2.74, p=0.0009]. Only a small portion of this association was explained by baseline differences in levels of IL-6, TNF-alpha and fibrinogen. Conclusions: In a contemporary cohort of patients with CAD, development of incident PAD was associated with adverse CV outcomes. The increased risk of CV events was not explained by shared risk factors or inflammation. Further research is necessary to understand how the presence of PAD increases risk of subsequent CV events.