title: Effect of beta blockers on central aortic pressure in African-Americans.
abstract: The objective of this study was to evaluate the vascular effects of heart rate (HR) reduction with BB therapy in African Americans (AA). Beta-blockers (BB) offer less cardiovascular protection than other hypertensive drugs. Studies of Caucasian subjects suggest this may be due to an adverse effect of HR lowering on arterial wave reflection. We studied 506 subjects (age 63 ± 14 years, 52% were treated with BB). Central systolic (C-SBP) and pulse pressure (C-PP), augmented pressure (AP), and augmentation index (AI) were obtained via applanation tonometry (Sphygmocor). On univariate analysis, HR correlated inversely with BB use, C-SBP, AP, and AI (all P < .001), but not P-SBP. Multivariate analysis showed P-SBP and HR to be major determinants of C-SBP (R(2) = 0.95). Generalized linear model analysis showed higher C-SBP (P < .05) and C-PP (P = .04), but similar P-SBP (P = .24) in the BB group. After HR adjustment, differences in C-SBP, C-PP, AI, and AP were attenuated, suggesting HR to be a determinant of C-SBP. BB use is associated with higher C-SBP and lower PPA in hypertensive AA despite similar P-SBP. C-SBP is HR-dependent. HR reduction with BB accounts for less effective central blood pressure control in AA, similar to that reported in Caucasians.
authors.affiliation: Division of Cardiovascular Medicine, State University of New York Downstate Medical Center, Brooklyn, New York 11203, USA.
authors.forename: Haroon
authors.initials: H
authors.lastname: Kamran
authors.forename: Louis
authors.initials: L
authors.lastname: Salciccioli
authors.forename: Carl
authors.initials: C
authors.lastname: Bastien
authors.forename: Patricia
authors.initials: P
authors.lastname: Castro
authors.forename: Abhishek
authors.initials: A
authors.lastname: Sharma
authors.forename: Jason M
authors.initials: JM
authors.lastname: Lazar
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D001741:Black or African American; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001011:Aorta / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects*; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000208:ethnology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged
chemical_list: D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents