Progression of peripheral arterial disease predicts cardiovascular disease morbidity and mortality

Abstract

Objectives: The purpose of this study was to examine the association of progressive versus stable peripheral arterial disease (PAD) with the risk of future cardiovascular disease (CVD) events.

Background: An independent association between PAD, defined by low values of the ankle-brachial index (ABI), and future CVD risk has been demonstrated. However, the prognostic significance of declining versus stable ABI has not been studied.

Methods: We recruited 508 subjects (59 women, 449 men) from 2 hospital vascular laboratories in San Diego, California. ABI and CVD risk factors were measured at Visit 2 (1990 to 1994). ABI values from each subject's earliest vascular laboratory examination (Visit 1) were abstracted from medical records. Mortality and morbidity were tracked for 6 years after Visit 2 using vital statistics and hospitalization data.

Results: In multivariate models adjusted for CVD risk factors, very low (<0.70) and, in some cases, low (0.70 < or = ABI <0.90) Visit 2 ABIs were associated with significantly elevated all-cause mortality, CVD mortality, and combined CVD morbidity/mortality at 3 and 6 years. Decreases in ABI of more than 0.15 between Visit 1 and Visit 2 were significantly associated with an increased risk of all-cause mortality (risk ratio [RR]: 2.4) and CVD mortality (RR: 2.8) at 3 years, and CVD morbidity/mortality (RR: 1.9) at 6 years, independent of Visit 2 ABI and other risk factors.

Conclusions: Progressive PAD (ABI decline >0.15) was significantly and independently associated with increased CVD risk. Patients with decreasing ABI may be candidates for more intensive cardiovascular risk factor management.

Figure 1. 3- and 6-Year All-Cause Mortality and CVD Events by ABI Category, Vascular Laboratory Patients, San Diego, California, Recruited 1990 to 1994

Mortality model are logistic, morbidity/mortality model is Cox. Models adjusted for age, gender, race, body mass index, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, log triglycerides, diabetes, hypertension, pack-years smoking, smoking status (current/past/never), history of coronary heart disease, history of stroke, claudication status and history of surgery for peripheral artery disease. *p < 0.05; **p < 0.01; ***p < 0.001. ABI = ankle-brachial index; CVD = cardiovascular disease.