Background: Femoral artery intima-media thickness (IMT), like carotid IMT, is a surrogate indicator of atherosclerotic coronary and peripheral vascular diseases in middle-aged and older adults. This study examined the cardiovascular disease risk profile of asymptomatic young adults with increased femoral artery IMT.
Methods: Femoral artery IMT was measured by B-mode ultrasonography in 1080 black and white subjects (aged 24-43 years; 71% white, 43% male) enrolled in the Bogalusa Heart Study. Individuals in the top (n=54) versus bottom fifth (n=54) percentiles distribution of femoral IMT were compared for traditional cardiovascular risk factors profile. Univariate analysis compared the two groups, t-tests and chi tests were performed.
Results: The top and bottom fifth percentiles of IMT differed with respect to age (P<0.001), systolic blood pressure (P<0.05), diastolic blood pressure (P<0.05), total cholesterol (P<0.01), low-density lipoprotein (LDL) cholesterol (P<0.001), non-high-density lipoprotein (HDL) cholesterol (P<0.01) and smoking status (P<0.01). In terms of prevalence of clinically defined traditional risk factors, individuals at the top versus bottom fifth percentile of IMT distribution had significantly higher prevalence of high LDL cholesterol (>OR=130 mg/dL), non-HDL cholesterol (>OR=160 mg/dL), and cigarette smoking. The odds ratio for individuals with three or more risk factors versus no risk factors having IMT in the top fifth percentile was 4.7 (P=0.01).
Conclusion: The observed adverse effect of cardiovascular risk factors on IMT of femoral artery, a surrogate measure of coronary and peripheral atherosclerosis, in asymptomatic young individuals underscores the need for risk factors profiling in early life. These observations have important implications in preventive medicine.