title: Ankle-brachial index and subclinical cardiac and carotid disease: the multi-ethnic study of atherosclerosis.
abstract: The authors studied associations between ankle-brachial index (ABI) and subclinical atherosclerosis in the Multi-Ethnic Study of Atherosclerosis. Participants included 3,458 women (average age = 62.6 years) and 3,112 men (average age = 62.8 years) who were free of clinically evident cardiovascular disease. Measurements included ABI, carotid artery intima-media thickness, and coronary artery calcium assessed with computed tomography. Five ABI categories were defined: <0.90 (definite peripheral arterial disease (PAD)), 0.90-0.99 (borderline ABI), 1.00-1.09 (low-normal ABI), 1.10-1.29 (normal ABI), and > or =1.30 (high ABI). Compared with that in men with normal ABI, significantly higher internal carotid artery intima-media thickness was observed in men with definite PAD (1.58 vs. 1.09; p < 0.001), borderline ABI (1.33 vs. 1.09; p < 0.001), and low-normal ABI (1.18 vs. 1.09; p < 0.001) after adjustment for confounders. Fully adjusted odds ratios for a coronary artery calcium score greater than 20 decreased across progressively higher ABI categories in both women (2.85 (definite PAD), 1.27 (borderline ABI), 1.11 (low-normal ABI), 1.00 (normal ABI; referent), and 0.78 (high ABI); p for trend = 0.0002) and men (3.26 (definite PAD), 1.72 (borderline ABI), 1.14 (low-normal ABI), 1.00 (normal ABI; referent), and 1.43 (high ABI); p for trend = 0.0002). These findings indicate excess coronary and carotid atherosclerosis at ABI values below 1.10 (men) and 1.00 (women) and may imply increased risk of cardiovascular events in persons with borderline and low-normal ABI.
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA. mdm608@northwestern.edu
authors.forename: Mary McGrae
authors.initials: MM
authors.lastname: McDermott
authors.forename: Kiang
authors.initials: K
authors.lastname: Liu
authors.forename: Michael H
authors.initials: MH
authors.lastname: Criqui
authors.forename: Karen
authors.initials: K
authors.lastname: Ruth
authors.forename: David
authors.initials: D
authors.lastname: Goff
authors.forename: Mohammed F
authors.initials: MF
authors.lastname: Saad
authors.forename: Colin
authors.initials: C
authors.lastname: Wu
authors.forename: Shunichi
authors.initials: S
authors.lastname: Homma
authors.forename: A Richey
authors.initials: AR
authors.lastname: Sharrett
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000842:Ankle / Q000098:blood supply*; D001161:Arteriosclerosis / Q000175:diagnosis* / Q000208:ethnology; D001916:Brachial Artery / Q000503:physiopathology*; D002340:Carotid Artery Diseases / Q000175:diagnosis* / Q000208:ethnology; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000208:ethnology; D003331:Coronary Vessels / Q000503:physiopathology*; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis* / Q000208:ethnology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D018570:Risk Assessment; D014057:Tomography, X-Ray Computed; D014481:United States