Contemporary risk factor control and walking dysfunction in individuals with peripheral arterial disease: NHANES 1999-2004

Background: Lower extremity peripheral arterial disease (PAD) is a coronary heart disease (CHD) risk equivalent. Selected studies have demonstrated less intense risk factor management and diminished mobility in individuals with PAD as compared to individuals with clinical recognized CHD. However, comparable data have not been reported from a nationally representative population. Objectives: To assess the prevalence, treatment, and control of cardiovascular risk factors among individuals with PAD as defined by an ankle-brachial index (ABI) <0.90 (but without recognized CHD) as compared with individuals with recognized CHD (but without PAD). A second objective was to evaluate the diagnostic accuracy of measures of walking dysfunction to identify individuals with PAD. Design, setting, and participants: We analyzed data from 7571 participants aged 40 or older who participated in the National Health and Nutrition Examination Survey (NHANES) 1999-2004, a nationally representative cross-sectional survey of the U.S. population. Results: The prevalence of PAD without CHD was 4.1% (95% CI 3.6-4.5) compared to 7.9% (7.1, 8.9) for CHD (without PAD). Hypertension prevalence was similar, but treatment and control rates were lower among individuals with PAD compared to CHD (treatment: 69% vs. 84%, p < 0.001; control: 50% vs. 63%, p = 0.01). Treatment of hypercholesterolemia was lower among individuals with PAD (54% vs. 79%, p < 0.001) but control was similar (83% vs. 85%, p = 0.78). Diabetes awareness, treatment, and control did not differ between the two groups. Walking mobility limitations were specific, but insensitive, for the identification of individuals with PAD. Conclusion: PAD in the absence of clinically recognized CHD is under-treated and poorly controlled in the general U.S. population. Leg symptoms are not adequate to identify individuals with PAD, who are at high risk of ischemic events.