title: Greater intima-media thickness in the carotid bulb is associated with reduced baroreflex sensitivity.
abstract: The aim of this study was to evaluate the association between resting baroreflex sensitivity (BRS) and carotid intima-media thickness (IMT), a putative marker of subclinical atherosclerosis. Participants were 64 men and 18 women (median age, 57 years; range, 40 to 70 years), who did not have a previous history of coronary artery disease or treatment for hypertension. Resting BRS was measured during a 9-min baseline period using the noninvasive sequence technique; carotid IMT was subsequently determined using ultrasonography. Hierarchical multiple regression analyses showed that greater IMT in the carotid bulb (an area with a high density of baroreceptors) was associated with reduced BRS. These findings remained after adjusting BRS for resting mean arterial pressure, age, body mass index, gender, and smoking history, R2 = 0.06, P = .03. In contrast, IMT in the common and internal carotid regions (areas with presumably lower baroreceptor densities) did not account for a significant proportion of the variance in BRS. These results suggest that subclinical atherosclerosis, specifically in a region with high baroreceptor density, is associated with a reduced sensitivity of the baroreflex.
authors.affiliation: Cardiovascular Behavioral Medicine Research Program, University of Pittsburgh, Pennsylvania, USA. pjg4@pitt.edu
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Gianaros
authors.forename: J Richard
authors.initials: JR
authors.lastname: Jennings
authors.forename: G Benedikt
authors.initials: GB
authors.lastname: Olafsson
authors.forename: Andrew
authors.initials: A
authors.lastname: Steptoe
authors.forename: Kim
authors.initials: K
authors.lastname: Sutton-Tyrrell
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Muldoon
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Manuck
mesh_terms: D000328:Adult; D000368:Aged; D001161:Arteriosclerosis / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D017704:Baroreflex / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination; D015992:Body Mass Index; D002339:Carotid Arteries / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D017539:Tunica Intima / Q000473:pathology; D017540:Tunica Media / Q000473:pathology; D014463:Ultrasonography