Vascular age: integrating carotid intima-media thickness measurements with global coronary risk assessment.
BACKGROUND
An imaging test that quantifies atherosclerotic burden and that can be integrated with existing risk stratification paradigms would be a very useful clinical tool.


OBJECTIVE
Measurement of carotid intima-media thickness (CIMT) is feasible in a clinical setting. Such measurements can be integrated into coronary risk assessment models.


METHODS
Carotid intima-media thickness was measured by B-mode ultrasound in 82 consecutive patients without manifest atherosclerotic vascular disease. The values were used to determine "vascular age" (VA) based on nomograms from the Atherosclerosis Risk in Communities study. Vascular age was substituted for chronological age and standard and vascular age-adjusted 10-year coronary heart disease (CHD) risk estimates were compared.


RESULTS
The mean chronological age was 55.8 +/- 9.0 years. The mean VA using CIMT was 65.5 +/- 18.9 years (p < 0.001). The Framingham 10-year hard CHD risk estimate was 6.5 +/- 4.9%. Substituting CIMT-derived VA for chronological age increased the 10-year CHD risk estimate to 8.0 +/- 6.8% (p < 0.001). Of 14 subjects initially at intermediate risk, 5 (35.7%) were reclassified as higher risk and 2 (14.3%) were reclassified as lower risk. Significant predictors of reclassification were tobacco use, high-density lipoprotein cholesterol, systolic blood pressure, and low-density lipoprotein cholesterol.


CONCLUSIONS
Measurement of CIMT, a noninvasive estimate of current atherosclerotic burden, is feasible in a clinical setting and can be integrated into CHD risk assessment models. Determining VA using CIMT values may help individualize the age component of population-based CHD risk estimates. This strategy should be tested in a large trial with hard clinical endpoints.
University of Wisconsin Atherosclerosis Imaging Research Program, Section of Cardiovascular Medicine, University of Wisconsin Medical School, Madison, Wisconsin 53792, USA.
James H
JH
Stein
Michael C
MC
Fraizer
Susan E
SE
Aeschlimann
Jane
J
Nelson-Worel
Patrick E
PE
McBride
Pamela S
PS
Douglas
D000328:Adult; D000367:Age Factors; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D017536:Carotid Artery, Common / Q000473:pathology* / Q000503:physiopathology; D008076:Cholesterol, HDL / Q000097:blood; D003327:Coronary Disease / Q000145:classification / Q000453:epidemiology / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D013599:Systole / Q000502:physiology; D017539:Tunica Intima / Q000473:pathology* / Q000503:physiopathology
D015415:Biomarkers; D008076:Cholesterol, HDL