Impact of carotid intima-media thickening on risk stratification in elderly hypertensives

Background: It has been shown that aging and arterial hypertension are both associated with an increased prevalence of carotid structural abnormalities, such as intima-media (IM) thickening or plaques, which are a powerful independent predictor of cardiovascular (CV) events. We investigated the impact of carotid IM thickening in profiling the absolute CV risk stratification according the 1999 World Health Organization/International Society of Hypertension (WHO/ISH) guidelines in elderly hypertensive patients. Methods: Two hundred and thirty untreated elderly patients (>65 years) referred to our outpatient hospital clinic were included in the study. They underwent the following procedures: (i) medical history, physical examination and clinic blood pressure measurement; (ii) routine blood chemistry and urine analysis; (iii) electrocardiogram. The risk was initially stratified according to the routine procedures indicated by WHO/ISH guidelines and subsequently reassessed by adding the results of carotid ultrasonography (IM thickening as diffuse IM thickness >0.9 and <1.3 mm). Results: According to routine classification 56% (=129) were medium-risk patients, 29% (n = 67) high-risk and 15% (n = 34) very-high-risk patients. The overall prevalence of carotid IM thickening was 54% (49% in medium-risk vs 60% in high or very high-risk patients, p < 0.05). A marked change in risk stratification was observed when IM thickening was taken in consideration: medium-risk patients decreased to 29% and high-risk rose to 56% (p < 0.01). Conclusions: Ultrasound assessment of large artery damage is extremely useful for a more accurate estimate of global CV risk in elderly hypertensives, because stratification based on diagnostic routine procedures can underestimate the overall risk in a large fraction of medium-risk subjects.