Prevalence of symptomatic and asymptomatic peripheral arterial disease and the value of the ankle-brachial index to stratify cardiovascular risk.

OBJECTIVES: To determine the prevalence of ankle-brachial index (ABI)<0.9 and symptomatic peripheral arterial disease (PAD), association with cardiovascular risk factors (CVRF), and impact of adding ABI measurement to coronary heart disease (CHD) risk screening.

DESIGN: Population-based cross-sectional survey of 6262 participants aged 35-79 in Girona, Spain.

METHODS: Standardized measurements (CVRF, ABI, 10-year CHD risk) and history of intermittent claudication (IC), CHD, and stroke were recorded. ABI<0.9 was considered equivalent to moderate-to-high CHD risk (> or =10%).

RESULTS: ABI<0.9 prevalence was 4.5%. Only 0.62% presented low ABI and IC. Age, current smoker, cardiovascular disease, and uncontrolled hypertension independently associated with ABI<0.9 in both sexes; IC was also associated in men and diabetes in women. Among participants 35-74 free of cardiovascular disease, 6.1% showed moderate-to-high 10-year CHD risk; adding ABI measurement yielded 8.7%. Conversely, the risk function identified 16.8% of these participants as having 10-year CHD risk>10%. In participants 75-79 free of cardiovascular disease, the prevalence of ABI<0.9 (i.e., CHD risk> or =10%) was 11.9%.

CONCLUSIONS: ABI<0.9 is relatively frequent in those 35-79, particularly over 74. However, IC and CHD risk> or =10% indicators are often missing. Adding ABI measurement to CHD-risk screening better identifies moderate-to-high cardiovascular risk patients.