The influence of obesity on the assessment of carotid intima-media thickness.

BACKGROUND: The assessment of carotid intima-media thickness (CIMT) may improve cardiovascular risk prediction. The optimal protocol for CIMT measurement is unclear. CIMT may be measured in the common carotid artery (CCA), carotid bifurcation (CB), and internal carotid artery (ICA), but measurements from CB and ICA are more difficult to obtain. We studied the influence of body mass index (BMI) and atheroma plaques on the capacity to obtain CIMT measurements at different carotid sites. METHODS: Using an automatic system, CIMT was measured in 700 subjects aged 45-75, in the near and far walls of CCA, CB, and ICA bilaterally. The presence of atheroma plaques, BMI and vascular risk factors were recorded. RESULTS: CIMT measurements in CCA were possible in all except one subject. It was not possible to obtain CIMT measurements at CB or ICA in 24.1% of normal weight and 58.8% of obese subjects. The likelihood of obtaining CIMT measurement at all carotid sites decreased as the BMI increased. Atheroma plaques in a carotid segment did not preclude CIMT measurement at this site. CONCLUSIONS: CIMT measurements in distal carotid segments are more challenging in obese subjects. Measuring CIMT at CCA remains feasible in obese subjects and should be the primary endpoint in these subjects. Nevertheless, CB and ICA measurements, when feasible, would improve risk classification.

Adaptation of the Framingham-Wilson coronary risk equation for the population of Navarra (RICORNA).

INTRODUCTION AND OBJECTIVES: The Framingham equations overestimate the risk of coronary disease in populations with a low disease incidence. It is more appropriate to take the local population's characteristics into account when estimating coronary risk. Accordingly, the Framingham-Wilson equation has been adapted for the population of Navarra, Spain. This article presents 10-year overall coronary risk charts. METHODS: The Framingham-Wilson equation was adapted using data on the prevalence of cardiovascular risk factors and the coronary event rate in the population of Navarra. The version of the Framingham-Wilson equation used included high-density lipoprotein cholesterol (HDL-C). The probability of an event at 10 years for different combinations of risk factors, with an HDL-C concentration of 35-59 mg/dL, are illustrated. RESULTS: Using the Framingham equation adapted for Navarra (i.e., the RICORNA or Riesgo Coronario Navarra), the proportion with an estimated probability of a coronary event in the next 10 years greater than 9% is approximately half that in the original Framingham population, and the proportion with a high or very high probability (i.e., 20%) is one-third. An HDL-C level <35 mg/dL increases the risk by 50% and a level > or =60 mg/dL reduces it by 50%, approximately. The average HDL-C level observed in the population was 63.9 mg/dL overall, and 70.1 mg/dL in women. CONCLUSIONS: The RICORNA equation can provide a more precise estimate of overall coronary risk and could be useful in primary disease prevention in Navarra. The high HDL-C concentration observed in Navarra might contribute to the associated low coronary morbidity and mortality.