Introduction: Cardiovascular disease (CVD) and cancer share risk factors, including smoking and obesity. Indeed, an increased cancer risk was reported among patients with CVD, such as myocardial infarction. Lower extremity peripheral artery disease (PAD) has also been explored in this context, but most previous studies included only Whites, had follow-up <10 years, or did not account for key confounders like smoking. Hypothesis: PAD is independently associated with long-term cancer risk in a bi-racial cohort. Methods: We studied 13,102 ARIC participants without prevalent cancer at visit 1 (1987-89) (mean age 54 [SD 6] years, 54% women, and 26% Black) (funding: NHLBI, NCI, and NPCR). Incident cancer was ascertained by linkage to cancer registries and medical record review. We categorized PAD status at visit 1 into symptomatic PAD (intermittent claudication or a history of lower extremity revascularization), asymptomatic PAD (ankle brachial index [ABI] ≤0.9), and other ABI categories of >0.9-1.0, >1.0-1.1, >1.1-1.2, >1.2-1.3 and >1.3. We ran multivariable Cox models. Results: During the median follow-up of 25 years (IQI 15-27 years), there were 4,142 incident cancer cases. 25-year cumulative cancer incidence was 48% in symptomatic PAD, 39% in asymptomatic PAD, and 31-34% in the other categories. When we adjusted for demographic factors, both symptomatic and asymptomatic PAD showed significant hazard ratios for incident cancer (1.79 [95%CI 1.33-2.43] and 1.39 [1.18-1.63], respectively, vs. ABI 1.1-1.2, Model 1 in Table ). After adjusting for additional potential confounders, including smoking and diabetes, these associations were somewhat attenuated but remained consistent (Models 2-4 in Table ). Conclusion: Both symptomatic and asymptomatic PAD were associated with an increased risk of cancer independently of smoking and diabetes. Although potential mechanisms should be explored, clinicians should be aware of this excess cancer risk among patients with PAD when considering cancer prevention and screening.
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