The relationship between blood pressure levels and cardiovascular risk is continuous and direct, and this makes any numerical definition and classification of hypertension arbitrary, the guidelines committee has stressed. Any numerical definitions must be flexible, resulting from evidence of risk and availability of effective and well-tolerated drugs. Since no new epidemiologic evidence has emerged since 1999, the WHO/ISH classification (also that of JNC 6,[6] but not JNC 7) has been retained (Table 1), with the reservation that the threshold for hypertension must be considered as flexible -- ie, higher or lower based on the total (global) cardiovascular risk profile of each individual. Accordingly, the definition of high-normal blood pressure includes values that may be considered as high (ie, hypertensive) in high-risk individuals or acceptable in those at lower risk.

Table 1. WHO/ISH Definition and Classification of Blood Pressure Levels

According to the guidelines, when a patient's SBP and DBP levels fall into different categories, the higher category should apply. Moreover, in older patients with isolated systolic hypertension, the blood pressure can also be assessed as grades 1, 2, and 3, according to SBP values in the ranges indicated, provided diastolic values are < 90 mm Hg.
In another departure, the ESH committee believes that use of the term "hypertension" should be avoided in classifying blood pressure, and instead used only to promote the case for tight blood pressure control. Notably, they avoid and do not support the term "prehypertension," as used in JNC 7, although they point out that they were not aware of the term when the new European guidelines were prepared.


编辑 郑麓薇