Racial differences in central blood pressure and vascular function in young men.
Young African-American men have altered macrovascular and microvascular function. In this cross-sectional study, we tested the hypothesis that vascular dysfunction in young African-American men would contribute to greater central blood pressure (BP) compared with young white men. Fifty-five young (23 yr), healthy men (25 African-American and 30 white) underwent measures of vascular structure and function, including carotid artery intima-media thickness (IMT) and carotid artery beta-stiffness via ultrasonography, aortic pulse wave velocity, aortic augmentation index (AIx), and wave reflection travel time (Tr) via radial artery tonometery and a generalized transfer function, and microvascular vasodilatory capacity of forearm resistance arteries with strain-gauge plethysmography. African-American men had similar brachial systolic BP (SBP) but greater aortic SBP (P<0.05) and carotid SBP (P<0.05). African-American men also had greater carotid IMT, greater carotid beta-stiffness, greater aortic stiffness and AIx, reduced aortic Tr and reduced peak hyperemic, and total hyperemic forearm blood flow compared with white men (P<0.05). In conclusion, young African-American men have greater central BP, despite comparable brachial BP, compared with young white men. Diffuse macrovascular and microvascular dysfunction manifesting as carotid hypertrophy, increased stiffness of central elastic arteries, heightened resistance artery constriction/blunted resistance artery dilation, and greater arterial wave reflection are present at a young age in apparently healthy African-American men, and conventional brachial BP measurement does not reflect this vascular burden.
Department of Kinesiology and Community Health, Exercise and Cardiovascular Research Laboratory, Rehabilitation Education Center, University of Illinois at Urbana-Champaign, 1207 S. Oak St. Champaign, IL 61820,USA. kheffeman@tuftsmedicalcenter.org
Kevin S
KS
Heffernan
Sae Young
SY
Jae
Kenneth R
KR
Wilund
Jeffrey A
JA
Woods
Bo
B
Fernhall
D000328:Adult; D001741:Black or African American; D001011:Aorta / Q000503:physiopathology; D001794:Blood Pressure; D001916:Brachial Artery / Q000503:physiopathology; D002339:Carotid Arteries / Q000503:physiopathology; D003430:Cross-Sectional Studies; D004548:Elasticity; D005542:Forearm / Q000098:blood supply; D006439:Hemodynamics; D006801:Humans; D006940:Hyperemia / Q000208:ethnology / Q000503:physiopathology; D008297:Male; D012039:Regional Blood Flow; D013997:Time Factors; D014652:Vascular Diseases / Q000208:ethnology* / Q000473:pathology / Q000503:physiopathology*; D014655:Vascular Resistance; D014664:Vasodilation; D044465:White People; D055815:Young Adult