Contrast of the impact of multiple cardiovascular risk factors on the femoral and carotid intima-media thickness in asymptomatic young adults: the Bogalusa Heart Study

Abstract

Objective: Impact of multiple cardiovascular (CV) risk factors on the intima-media thickness (IMT) of femoral and carotid artery segments measured simultaneously has not been studied in asymptomatic adults. This study examined the impact of multiple CV risk factors on the IMT in asymptomatic adults.

Methods: Femoral and carotid IMT were measured by B-mode ultrasonography in 1080 asymptomatic subjects (aged 24-43 years) of the Bogalusa Heart Study.

Results: In multivariate analyses, systolic blood pressure, age, male, total cholesterol/HDL cholesterol ratio and smoking were common independent predictor variables for the femoral and carotid IMT. Systolic blood pressure followed by age were the major determinant risk factors for the IMT of all arterial segments except carotid bulb for which age was the major predictor. The independent variables listed explained 11% of the variability in femoral IMT, 28% in common carotid, 18% in carotid bulb, 10% in internal carotid and 27% in composite carotid segments. Mean IMT increased with increasing number of risk factors in all arterial segments; p for trend=0.003 for femoral and 0.001 for all carotid segments.

Conclusions: The observed deleterious trend of increasing IMT of the femoral and different segments of the carotid artery with increasing number of CV risk factors provide evidence of silent systemic atherosclerosis in asymptomatic young adults. These findings underscore the importance of multiple for risk factors profiling in early life. Studies of the femoral and carotid IMT may be helpful along with measurements of risk factors for evaluation of asymptomatic atherosclerotic disease.

Figure 1. The effect of multiple risk factors on IMT of femoral artery and different segments of carotid artery in young adults. The Bogalusa Heart Study

A highly significant trend of increasing thickness is shown with greater numbers of risk factors. Risk factors included were total cholesterol / HDL cholesterol ratio, waist circumference, systolic blood pressure, insulin level (75^th percentile specific for age, race, gender) and smoking. p for trend = 0.003 for femoral; p for trend = 0.001 for CCA, bulb, ICA and composite carotid CCA, common carotid artery; Bulb, carotid bulb; ICA, internal carotid artery; Com, composite carotid.