I must state at the outset that the hypertension experts who served on the Executive Committee for the Eighth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 8) were true experts in hypertension and genuinely good people. They honored their oath of silence and revealed nothing of the outcomes of their deliberations. I served with many of them on the Executive Committee of JNC 7 and know all of them both professionally and personally.
It is difficult to fault the Institute of Medicine (IOM) for their response to poorly conceived guidelines by other groups. Some guidelines were not rigidly evidence‐based and some were thought to have been influenced by fiscal relationships between members and industry. The IOM established a process that drove not only JNC 8 but also other guidelines such as the Fourth Report of the Adult Treatment Panel (ATP IV) that were to be published all together. As it happened, the effort seemed to have been expended on the process and the process itself turned out to be the deliverable. Although the National Heart, Lung, and Blood Institute (NHLBI) Web site indicates that the report was written, it seems not to have undergone the next step: review by an advisory council.
JNC 8 was so long delayed by the process that it became the butt of jokes, with “JNC Late” being one of the kinder ones. The process was publicly released at several scientific meetings. The focus had been reduced to 3 key questions and it was made clear that nothing beyond those questions would be addressed. The questions were in brief: When to initiate treatment, what are the goal blood pressures, and how do you get to goal? An outside vendor reviewed 6136 English‐language papers and rated 148 (2.4%) of them “good” or “fair” for the evidence base. Of these 148 vetted papers, 40 (27%) were deemed to be “good.” That is, the “good” evidence base comprised 0.65% of the papers reviewed.
The Executive Committee of JNC 7 was hard driven by Claude Lenfant, ably chaired by Aram Chobanian, and brilliantly facilitated by Edward Roccella. The many face‐to‐face meetings were open and the process was as evidence‐based as the available evidence permitted. A medical librarian had a direct line to the National Library of Medicine so that factual issues could be researched online in seconds to minutes and the actual text of published papers projected onto a screen for all to see and discuss. The process was heavily participatory with members chairing relevant subcommittees. Guidelines were field‐tested in real time with practicing clinicians in order to determine their feasibility. A verdict of “we can't do that” killed any proposed guideline. The Committee appreciated that not all questions could be answered with quality published evidence. At some point, expert opinion had to prevail for some questions.
Practicing clinicians seek guidelines to help them manage their patients. The problem is that there is no set of guidelines that covers 100% of the patient population. There is a distribution curve of patient response to any given treatment. If the curve is normal, approximately 67% (1 standard deviation) is likely to fall within the guideline. By definition, those at either “tail” beyond 2 standard deviations will be about 2.5% of the population at either end and may not be part of the evidentiary pool from which guidelines are created. A hypertension specialist with a purely referral practice such as myself can be assured of a patient population that is 100% outside of the 95%; otherwise they would not have been referred in the first place.
Even the best clinical trials are based on a small—even tiny—subset of the population for which the trial conclusions are intended. The ability to generalize results to that overall population is one of the challenges of clinical trial design. Furthermore, good clinical trials are intensely monitored to ensure that all of the participating centers, clinics, and their personnel are following the protocol exactly as it was written. Other than tight quality control in some multispecialty practice groups and with some quality monitoring by managed care organizations, there is nothing that enforces individual practitioners to adhere to guidelines. The message is that any given patient may not fit into the intended population for a given guideline and, even if they do, there is nothing to force the practitioner to adhere to it. It simply is not a perfect world out there. That does not keep us and the IOM from trying, but some semblance of reality testing is necessary to move forward.
It would appear that the NHLBI came to the conclusion that their appointed task could not be accomplished as designed. Instead they have opted to be in the business of establishing process and evidence‐based facts generated by that process. These facts would then be made available to specialty organizations such as the American Society of Hypertension so that they could generate their own guidelines specific to their specialty, patient population, and expertise.
Perhaps this is a good thing.