Impact of preclinical carotid atherosclerosis on global cardiovascular risk stratification and events in a 10-year follow-up: comparison between the algorithms of the Framingham Heart Study, the European SCORE and the Italian 'Progetto Cuore'

BACKGROUND: The aim of the study was to compare three widely used algorithms for stratification of the global cardiovascular risk (GCVR): the Framingham Heart Study (FHS) score, the European systemic coronary risk estimation (SCORE) and the Italian 'Progetto Cuore' (heart project) score. It was also investigated how preclinical carotid atherosclerosis (pre-ATS) might influence the incidence and improve the risk prediction of cerebrovascular and cardiovascular events. METHODS: Subjects (n = 358) without previous history of cardiovascular disease (CVD) were recruited and the GCVR was calculated for each patient. An ultrasound evaluation of the carotid arteries was also performed. RESULTS: According to SCORE, the recruited population had globally a low risk of cardiovascular mortality and the risk equation estimated a GCVR of 2% in spite of the in spite of the observed rate of 0.8% (95% CI -0.001 to 0.02) of fatal events. The FHS and the 'Progetto Cuore' risk equations, regarding a 10-year risk of fatal and nonfatal events, predicted a low GCVR of 31 and 30%, an intermediate risk of 64 and 66%, and a high risk of 5 and 4% of the population respectively. They also estimated a general GCVR of 6.9 and 6.4% respectively versus an observed event rate 27.7 (95% CI 23.0 to 32.0). The discriminative power, calculated with the area under the receiving operator curve (AUROC), was 0.53 for SCORE, 0.54 for FHS and 0.55 for Progetto Cuore. Based on the ultrasound evaluation of carotid arteries, a first clinical event at 10-year follow-up was reported in 3% of subjects with normal ultrasound examination, 32% with intima-media thickening (IMT) and 62% with asymptomatic carotid plaque (ACP). CONCLUSION: The present study has evaluated for the first time the prediction of GCVR in an asymptomatic population, comparing three different risk scores. Carotid pre-ATS was related to the major cardiovascular risk factors (RFs) and was independently associated with a major incidence of cerebro- and cardiovascular events, therefore enhancing the predictive value of the three different risk scores.