Conventional cardiovascular risk factors have been used to identify subgroups at increased risk of cardiovascular events. The British Regional Heart Study Score (BRHSS) using such risk factors at best identifies only 59% of individuals that develop coronary heart disease (CHD) in the subsequent 5 years. To identify a high risk subgroup in the BRHS a new approach has been the use of ultrasound to study arterial wall thickening, presence or absence of plaques and plaque type, to try and increase the predictive value of the BRHS Score.
Methods: Two towns (Dewsbury and Maidstone) of the British Regional Heart Study were selected because they have the highest and lowest prevalence of cardiovascular disease in the U.K. respectively. A total of 418 men and 397 women were surveyed and their carotid and common femoral bifurcations scanned.
Results: Total plaque thickness, carotid intima-media thickness (IMT), ultrasonic arterial score (UAS) and sum of plaque types reversed, were found to be the most significant explanatory variables in a multiple linear regression model with an r = 0.505 and R2 = 0.255. They could identify a subgroup of 25% of the population that contained 78% of cardiovascular deaths.
Conclusion: These findings appear to suggest the presence of plaques, the collective information from the echomorphology of these lesions and their absolute measures are far more predictive of risk.