[From labile or borderline arterial hypertension to mild hypertension. Current data and practical management]

The concept of labile hypertension (also called borderline hypertension) has been proposed to define those patients in whom blood pressure is sometimes below, sometimes above the frontier which separates normal and high blood pressure. Current evidence does not support the individualization of this concept, since numerous studies have demonstrated a similar or even higher blood pressure variability in hypertensive patients than that found in normotensive patients. The main objective, when measuring blood pressure, is to assess the risk of a cardiovascular event. It has been shown that the average value of several blood pressure determinations provides a better estimate of cardiovascular risk, and correlates better with hypertensive target organ disease, than a single blood pressure measurement. Therefore, we propose to define these so-called labile hypertensive patients on the basis of the average and to classify them into the category of mild hypertension, the later being defined as a diastolic blood pressure between 90 and 105 mmHg on several occasions according to the WHO. The increase in cardiovascular risk carried by a mild elevation in blood pressure, either untreated or treated with general health measures, is small, approximately 3% per year. Moreover, whereas the beneficial effects of pharmacological antihypertensive therapy have been demonstrated on a whole population basis, these effects remain controversial on an individual basis. Thus, it appears justified to give these hypertensive patients general health measures advice without any pharmacological therapy during the first months of follow-up. During this time, blood pressure measurements are repeated so that blood pressure status, and thus the need for pharmacological therapy, can be assessed more precisely.