title: Associations of ankle-brachial index with clinical coronary heart disease, stroke and preclinical carotid and popliteal atherosclerosis: the Atherosclerosis Risk in Communities (ARIC) Study.
abstract: The resting ankle-brachial index (ABI) is a non-invasive method to assess the patency of the lower extremity arterial system and to screen for the presence of peripheral occlusive arterial disease. To determine how the ABI is associated with clinical coronary heart disease (CHD), stroke, preclinical carotid plaque and far wall intimal-medial thickness (IMT) of the carotid and popliteal arteries, we conducted analyses in 15 106 middle-aged adults from the baseline examination (1987-1989) of the Atherosclerosis Risk in Communities (ARIC) Study. The prevalence of clinical CHD, stroke/transient ischemic attack (TIA) and preclinical carotid plaque increased with decreasing ABI levels, particularly at those of < 0.90. Individuals with ABI < 0.90 were twice as likely to have prevalent CHD as those with ABI > 0.90 (age-adjusted odds ratio (OR) ranging from 2.2 (95% CI: 1.0-5.1) in African-American men to 3.3 (95% CI: 2.1-5.0) in white men). Men with ABI < 0.90 were more than four times as likely to have stroke/TIA as those with ABI > 0.90 (age-adjusted OR: 4.2 (95% CI: 1.8-9.5) in African-American men and 4.9 (95% CI: 2.6-9.0) in white men). In women the association was weaker and not statistically significant. Among those free of clinical cardiovascular disease, individuals with ABI < or = 0.90 had statistically significantly higher prevalence of preclinical carotid plaque compared to those with ABI > 0.90 (age-adjusted ORs ranging from 1.5 (95% CI: 1.0-1.9) in white women to 2.6 (95% CI: 1.0-6.6) in african-american men). The ABI was also inversely associated with far wall IMT of the carotid arteries (in both men and women) and the popliteal arteries (in men only). The associations of ABI with clinical CHD, stroke, preclinical carotid plaque and IMT of the carotid and popliteal arteries were attenuated and often not statistically significant after further adjustment for LDL cholesterol, cigarette smoking, hypertension and diabetes. These data demonstrate that low ABI levels, particularly those of < 0.90, are indicative of generalized atherosclerosis.
authors.affiliation: Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill, USA. zheng_z@epivax.epi.umn.edu
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Zheng
authors.forename: A R
authors.initials: AR
authors.lastname: Sharrett
authors.forename: L E
authors.initials: LE
authors.lastname: Chambless
authors.forename: W D
authors.initials: WD
authors.lastname: Rosamond
authors.forename: F J
authors.initials: FJ
authors.lastname: Nieto
authors.forename: D S
authors.initials: DS
authors.lastname: Sheps
authors.forename: A
authors.initials: A
authors.lastname: Dobs
authors.forename: G W
authors.initials: GW
authors.lastname: Evans
authors.forename: G
authors.initials: G
authors.lastname: Heiss
mesh_terms: D000842:Ankle; D001161:Arteriosclerosis / Q000503:physiopathology*; D044383:Black People; D001916:Brachial Artery / Q000503:physiopathology*; D002340:Carotid Artery Diseases / Q000503:physiopathology; D002561:Cerebrovascular Disorders / Q000503:physiopathology*; D003327:Coronary Disease / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011150:Popliteal Artery; D012307:Risk Factors; D044465:White People; D001741:Black or African American