Subsequent risk of cancer among adults with peripheral artery disease in the community: The atherosclerosis risk in communities (ARIC) study.

BACKGROUND AND AIMS: Several studies reported an increased cancer risk related to lower-extremity peripheral artery disease (PAD) but had important caveats: not accounting for key confounders like smoking, follow-up <10 years, or no race-specific results. To assess the long-term independent association of PAD with cancer incidence in a bi-racial community-based cohort.

METHODS

We categorized 13,106 ARIC participants without cancer at baseline (mean age 54.0 [SD 5.7] years, 45.7 % male, and 26.1 % Black) into symptomatic PAD (clinical history or intermittent claudication), asymptomatic PAD (ankle-brachial index [ABI] ≤0.9), and five ABI categories (0.1-interval between 0.9 and 1.3 and > 1.3). We used cancer registries and medical records to ascertain cancer cases and ran multivariable Cox models.

RESULTS

During the median follow-up of 25.3 years, there were 4143 incident cancer cases. 25-year cumulative incidence was 37.2 % in symptomatic PAD, 32.3 % in asymptomatic PAD, and 28.0-31.0 % in the other categories. Symptomatic and asymptomatic PAD remained significantly associated with cancer incidence after adjusting for potential confounders, including smoking and diabetes (hazard ratio [HR] 1.42 [1.05-1.92] and 1.24 [1.05-1.46], respectively). When stratified by smoking status, we observed a robust association of PAD (symptomatic and asymptomatic combined) vs. no PAD with cancer risk in ever smokers (HR 1.42 [1.21-1.67]) but not in never smokers. The results were most evident for lung cancer (HR 2.16 (95 %CI 1.65-2.83) for PAD vs. no PAD within ever smokers).

CONCLUSIONS

Symptomatic and asymptomatic PAD conferred cancer risk, particularly among ever smokers and for lung cancer. Patients with PAD should receive evidence-based cancer prevention and screening.