Hypoechoic plaque at US of the carotid artery: an independent risk factor for incident stroke in adults aged 65 years or older. Cardiovascular Health Study.
OBJECTIVE
To investigate the association between incident (first) stroke and the echogenicity of internal carotid arterial plaque at ultrasonography (US).


METHODS
A cohort of 4, 886 individuals who, at baseline, were 65 years of age or older and without symptoms of cerebrovascular disease was followed up for an average of 3.3 years. Baseline clinical findings were from color Doppler and duplex US studies of the carotid arteries and a record of traditional risk factors: age, sex, presence of diabetes mellitus, pack-years of cigarette smoking, presence of hypertension, elevated systolic and diastolic blood pressure, elevated low-density lipoprotein cholesterol level.


RESULTS
Incident strokes, excluding hemorrhagic strokes and strokes of cardiac origin, were seen in 104 individuals (2.1%) at risk. Age- and sex-adjusted odds ratios for incident stroke were significant for hypoechoic plaque (odds ratio, 2.53; 95% CI, 1,42,4.53). After controlling for risk factors in a Cox proportional hazards model, the relative risk (RR) of incident stroke was 1.72 (p = .015) for hypoechoic plaque and 2.32 (P = .004) for internal carotid arterial narrowing of at least 50%. In addition, hypoechoic plaque (RR, 2.78; CI, 1.36,5.69) and 50%-100% stenosis (RR, 3.08; CI, 1.28, 7.41) were associated with ipsilateral, nonfatal stroke.


CONCLUSIONS
In asymptomatic adults aged 65 years or older, that risk of incident stroke was associated with two US features: hypoechoic internal carotid arterial plaque and an estimated internal carotid arterial stenosis of 50%-100%.
Dept of Radiology, Brigham and Women's Hospital, Boston, MA 02115, USA.
J F
JF
Polak
L
L
Shemanski
D H
DH
O'Leary
D
D
Lefkowitz
T R
TR
Price
P J
PJ
Savage
W E
WE
Brant
C
C
Reid
D000368:Aged; D000369:Aged, 80 and over; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D016893:Carotid Stenosis / Q000000981:diagnostic imaging*; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D002537:Intracranial Arteriosclerosis / Q000000981:diagnostic imaging*; D008297:Male; D016016:Proportional Hazards Models; D012306:Risk; D018616:Ultrasonography, Doppler, Duplex; D017585:Ultrasonography, Doppler, Transcranial