Greater intima-media thickness in the carotid bulb is associated with reduced baroreflex sensitivity.
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.
Gianaros
Peter J
PJ
Cardiovascular Behavioral Medicine Research Program, University of Pittsburgh, Pennsylvania, USA. pjg4@pitt.edu
Jennings
J Richard
JR
Olafsson
G Benedikt
GB
Steptoe
Andrew
A
Sutton-Tyrrell
Kim
K
Muldoon
Matthew F
MF
Manuck
Stephen B
SB
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