Association of soluble cell adhesion molecules with ankle-brachial index in a biethnic cohort of predominantly hypertensive individuals.

BACKGROUND Higher plasma concentrations of soluble adhesion molecules have been shown to be associated with increased risk of cardiovascular events. We investigated the association of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) with ankle-brachial index (ABI), a measure of peripheral arterial disease (PAD), in a biethnic cohort of adults without known coronary heart disease or stroke. METHODS Participants included 1102 blacks (mean age, 63 years; 74% women) and 1013 non-Hispanic whites (mean age, 58 years; 59% women) belonging to sibships ascertained on the basis of hypertension. We measured plasma concentrations of sICAM-1 and sVCAM-1 using high-sensitivity immunoassays and ABI using a standard protocol; PAD was defined as ABI <0.9. We used generalized estimating equations to assess whether sICAM-1 and sVCAM-1 were associated with ABI and PAD, independently of conventional risk factors. RESULTS After adjustment for conventional risk factors, blacks with sICAM-1 and sVCAM-1 concentrations in the highest quartiles had lower ABIs than those in the lowest quartiles (mean ABI 1.02 vs 0.98, P = 0.007, vs 1.02 vs 0.99, P = 0.003, respectively). In multivariable logistic regression analysis, sICAM-1 and sVCAM-1 concentrations in the highest quartiles were each associated with a higher odds ratio of having PAD, compared with the lowest quartiles: odds ratio (95% CI): 5.2 (1.8-15.2) and 2.2 (1.0-4.8), respectively. In contrast, in non-Hispanic whites, sICAM-1 and sVCAM-1 concentrations were not associated with ABI or PAD. CONCLUSIONS Higher sICAM-1 and sVCAM-1 concentrations were independently associated with lower ABI and PAD in blacks, but not in non-Hispanic whites.