Peripheral arterial disease in a multiethnic national sample: the role of conventional risk factors and allostatic load.

BACKGROUND Limited data exist on the prevalence of peripheral arterial disease (PAD) among ethnically diverse populations. Our objectives were to assess the prevalence of PAD in a multiethnic national sample and examine risk factor control and allostatic load (a marker of dysregulation of the inflammatory, metabolic, and cardiovascular systems) by race/ethnicity among individuals with PAD. METHODS We analyzed data from the 1999-2002 National Health and Nutrition Examination Survey for individuals aged > or =40 with a measured ankle brachial index (N=5,083). PAD was defined as an ankle brachial index <0.9. We performed bivariate and multivariate analyses to describe the association of race/ethnicity with PAD, controlling for sociodemographic factors, clinical risk factors and allostatic load. RESULTS Rates of PAD were higher among African Americans (7.8%) than Whites (3.4%) or Mexican Americans (5.1%) (P<.001). African Americans with PAD were more likely to be taking antihypertensive medications, were less likely to report vigorous physical activity, and had higher allostatic load scores than Whites. Although 95% of individuals with PAD report a routine place for care, almost half had a measured blood pressure >140/90 mm Hg, 28% were smokers, and 61% had a cholesterol value > or =200 mg/dL. CONCLUSIONS Within this nationally representative sample, African Americans had the highest rates of PAD. Although conventional risk factor control, including control of hypertension and hyperlipidemia, were similar between racial groups, African Americans with PAD had higher allostatic load scores. Among all individuals with PAD, evidence showed suboptimal cardiovascular risk factor control.