JNC 8 or Too Much of a Good Thing

The claim that “too much of a good thing is wonderful” has been attributed to Mae West. Her observation, however, does not apply to guidelines for the treatment of hypertension.

In the past few weeks, new guidelines have been proposed by at least four groups: members of the Eighth Joint National Committee (JNC 8),1 the American Society of Hypertension/International Society of Hypertension (ASH/ISH),2 the European Society of Hypertension/European Society of Cardiology (ESH/ESC),3 and the American Heart Association (AHA).4 These come on top of new guidelines from Canada5 and the United Kingdom.6 Despite spending a goodly amount of time in reading the literature about hypertension, I may have missed a few.

With much less time and interest, what are busy practitioners (the audience to whom the guidelines are addressed) to do? Very likely they will change very little from their current management of hypertension, at least until someone requires a certain level of blood pressure to be reached in their hypertensive patients in order to receive payment from various third‐party payers.

The Need for Unanimity

Medical practices logically may differ in different places at different times. However, those experts who compose guidelines are aware of the same data upon which guidelines are based. Why then do guidelines differ?

Some differences are based on the availability of new data, as between JNC 7 and JNC 8. But the major reason for differences between the four guidelines proposed over the same time period of the past few weeks likely reflects the willingness to accept evidence from observational data or meta‐analyses that include relatively small trials of limited duration by all but JNC 8.1 The JNC 8 guidelines accept data only from large randomized controlled trials and when such data are not available from “expert opinion.” Not surprisingly, JNC 8 backs away from the inadequate support for lower goals for patients with diabetes or chronic kidney disease and those older than 60 years.

Even though the editor of the second most cited journal of hypertension is heartened by the similarities in the ASH/ISH and ESH/ESC guidelines,7 the different levels of blood pressure wherein drug therapy is required and the different goals of therapy between JNC 8 and the other three is a major difference.

Meanwhile, advocacy has been given to the concept that treatment be based not on levels of blood pressure, ie, “treatment to target,” but rather on overall cardiovascular risk, ie, “benefit‐based tailored regimen,” although the assessment of risk does include a level of blood pressure.8 The “benefit‐based tailored regimen” is claimed to provide greater protection from cardiovascular diseases with less medication.

The approach suggested by Sussman and colleagues8 is in keeping with the recently published new guidelines for treatment of hypercholesterolemia,9 which have been both praised as being “a brave and wise departure from current practice”10 but also said to result in both undertreatment for some and overtreatment for others.11

For the foreseeable future, treatment to target will likely be continued. But beyond that issue, some greater uniformity over the two major issues—when to start drug treatment and what is the goal of therapy to be reached—is essential if both patients and practitioners are to be convinced of the best way to treat hypertension.