Aortic Stiffness Versus Framingham Score as Independent Predictors of Coronary Heart Disease in Hypertensive Patients
Background : Although various studies reported that pulse pressure, an indirect index of arterial stiffness, was an independent risk factor for coronary heart disease (CHD), a direct relationship between arterial stiffness and CHD remained to be established in patients with essential hypertension. Methods: A cohort of 1212 essential hypertensives patients, who had a measurement of arterial stiffness between 1980 and 1996, was studied. At entry, aortic stiffness was assessed from the carotid-femoral pulse wave velocity (PWV). A coronary disease prediction algorithm (Wilson P et al. Circulation 1998), based on the Framingham Heart Study (Framingham algorithm, FA), was calculated according to categories of sex, age, blood pressure, cholesterol, diabetes, and smoking, but not PWV. The ranges of FA and PWV values, included within the 1st and the 9th deciles, were 2-11 points and 8-16 m/s, respectively. CHD included fatal and non fatal myocardial infarction, coronary revascularization, and angina pectoris. The Cox proportional hazard regression model was used to estimate the relative risk (RR) of CHD. Results : Mean age at entry was 52±13 years (mean±SD). The mean delay to the first CHD event was 69±63 months. Seventy-three fatal and non fatal CHD events occurred. In this French population, the FA significantly predicted the occurence of CHD in the whole population (RR=1.10 (1.03-1.17) for 1 point of FA, P<0.01), but not in patients devoid of cardiovascular disease (other than hypertension) at entry. PWV was a significant independent predictor of CHD not only in the whole population (RR=1.07(1.02-1.12) for 1 m/s PWV, P<0.01), but also in patients devoid of previous cardiovascular disease at entry (primary events) (RR=1.11 (1.02-1.20), P=0.01). The predictive value of PWV remained unchanged after adjustment for FA and pulse pressure. Conclusion : This study provides the first direct evidence that aortic stiffness is an independent predictor of CHD in patients with essential hypertension. Aortic stiffness alone has a similar predictive value than the Framingham algorithm for CHD, and a better predictive value for primary CHD events.