Risk stratification for the prevention of cardiovascular complications of hypertension.

Abstract

Arterial hypertension is a well established risk factor for both coronary artery disease (CAD) and stroke. The decision to treat hypertension and prevent cardiovascular complications has, for many years, been based on the level of blood pressure. The present review, based on a cross-sectional and careful analysis of major trials, emphasises the need to assess the cardiovascular risk for each patient in order to make appropriate treatment decisions. Evaluation of cardiovascular risk in untreated hypertensive subjects indicates that coronary risk is two to three times higher than cerebrovascular risk. The same results have been observed in outcome trials where hypertensive patients were treated with antihypertensive drugs. Even though the results of outcome trials for antihypertensive drugs can be explained by blood pressure differences between randomised groups, antihypertensive drugs are, for the same reduction in blood pressure, more efficient in preventing cerebrovascular events than in preventing (CAD). Meta-analysis indicates that each reduction of 2 mmHg in systolic blood pressure levels is associated with a 25% reduction in stroke events, but a difference of at least 5 mmHg for systolic pressure between groups is necessary to obtain prevention of coronary events. A number of controlled trials using statins have shown that these drugs were particularly effective in preventing coronary disease. An appropriate therapeutic strategy for cardiovascular risk reduction in hypertensive patients should therefore include both antihypertensive therapy and prescription of a statin. The efficacy of this strategy was recently reported in the ASCOT trial, which estimated that for 100 hypertensive patients with a high cardiovascular risk and followed up for 10 years, the number of coronary events is 13, 10 and 7 for those without antihypertensive treatment, with antihypertensive therapy only and with both antihypertensive therapy and statin therapy, respectively.