Authors of the new U.S. guidelines for prevention and treatment of hypertension say they will decrease cardiovascular mortality, but other experts believe the guidelines are based on faulty research. The guidelines are published in the May 21st issue of the Journal of the American Medical Association. Critiques of the new guidelines are published in the May issue of the American Journal of Hypertension.

The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure was released at a news conference at the National Institutes of Health, and it appears in the May 21st issue of the Journal of the American Medical Association. The authors believe the guidelines represent a more aggressive approach to hypertension that will reduce the incidence of myocardial infarctions and ischemic strokes. However, the authors note that patient motivation is vital for any therapy to be effective in achieving blood pressure goals.

The May issue of the American Journal of Hypertension includes separate editorials from researchers in cardiology, endocrinology, and nephrology that dispute the research basis for the report’s conclusions and state reservations to the guidelines themselves.

The Report:

The report provides guidelines for increasing awareness, prevention, treatment, and control of hypertension. The Joint Committee, which consists of 39 major professional, public, and voluntary organizations, as well as 7 federal agencies, released the previous report in 1997.

The decision to develop a new report was based on four factors, according to the authors: "publication of many new hypertension observational studies and clinical trials; need for a new clear and concise guideline that would be useful for clinicians; need to simplify the classification of blood pressure; and a clear recognition that the Joint National Committee reports were not being used to their maximum benefit."

There are seven major points in the new report, relating to age norms for blood pressure, hypertension as a risk factor for cardiovascular disease, identification of high-risk , or prehypertensive, people, recommendations for first- and second-line medications for hypertension, and the role of patient motivation in the success of any clinical plan.

First, the report states that a systolic blood pressure of more than 140 mm Hg is a much more important risk factor for cardiovascular disease than diastolic blood pressure in adults over 50 years of age.

The risk for cardiovascular disease begins with a blood pressure of 115/75 mm Hg, and it doubles with each increment of 20/10 mm Hg. People who have normal blood pressure at age 55 years still have a 90 percent lifetime risk for developing hypertension.

In recognition of the association between lower blood pressure levels and cardiovascular risk, physicians should identify patients with a systolic pressure of 120 to 139 mm Hg or a diastolic pressure of 80 to 89 mm Hg as prehypertensive. These patients require counseling on health-promoting lifestyle modifications that may prevent cardiovascular disease.

Thiazide-type diuretics should be used as the drug treatment component for most patients with uncomplicated hypertension, either alone or combined with drugs from other classes. Certain high-risk conditions strongly suggest initial use of other antihypertensive drug classes such as angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, beta-blockers, and calcium-channel blockers.

Most patients with hypertension will require 2 or more antihypertensive medications to achieve a goal blood pressure of less than 140/90 mm Hg, or less than 130/80 mm Hg for patients with diabetes or chronic kidney disease.

If a patient’s baseline blood pressure is more than 20/10 mm Hg above goal level, physicians should consider beginning therapy with 2 agents, 1 of which usually should be a thiazide-type diuretic.

The last general recommendation is based on the observation that even the most effective therapy prescribed by the most careful clinician will control hypertension only if patients are motivated. Motivation improves when patients have positive experiences with and trust in the clinician. Empathy builds trust and is a potent motivator. The authors concluded, "Finally, in presenting these guidelines, the committee recognizes that the responsible physician's judgment remains paramount."

The authors also discussed public health approaches to decreasing the prevalence of hypertension and associated morbidity and mortality: "The Joint National Committee endorses the American Public Health Association resolution that the food manufacturers and restaurants reduce sodium in the food supply by 50 percent during the next decade. When public health intervention strategies address the diversity of racial, ethnic, cultural, linguistic, religious, and social factors in the delivery of their services, the likelihood of their acceptance by the community increases. These public health approaches can provide an attractive opportunity to interrupt and prevent the continuing costly cycle of managing hypertension and its complications."

In an editorial that accompanied the report, Thomas E. Kottke, M.D., M.S.P.H., wrote
" ... the [Joint National Committee] report reinforces several other messages, including that thiazide diuretics, the least expensive antihypertensive drugs, are also among the most effective for patients who do not have a compelling need for more expensive medications. Moreover, lifestyle interventions are effective for prevention and treatment of hypertension. However, the report also documents the failure of the health care system to translate current knowledge about hypertension into action. ... Hypertension awareness has not changed in the past decade and treatment rates have increased by less than 10 percent. Control rates are stagnant at 34 percent, far short of the Healthy People 2010 goal of 50 percent. Failing to take advantage of the knowledge that research has generated represents a wasted opportunity to improve and prolong the lives of individuals everywhere and to avert a looming chronic disease crisis. The majority of cases of hypertension can be prevented and controlled but this requires commitment to the task."

Other reaction to the report:
In separate editorials in the May issue of the American Journal of Hypertension, experts in the fields of cardiology, endocrinology, and nephrology write that the new treatment guidelines are built on a flawed foundation that gives inappropriate influence to one drug class, thiazide diuretics.
In particular, the editorial authors discuss the influence on the guidelines of one study: the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). The editorial writers state that the study had a faulty design, that data analysis was arbitrary, and that major conclusions were ‘spun’ to fit a particular point of view. The editorials also address the inappropriate use of large clinical trials to formulate treatment guidelines.
John H. Laragh, MD, cardiologist and editor-in-chief of the journal, wrote. “In reading [the new report], I find its recommendations bad medicine. Giving the diuretic chlorthalidone to every hypertensive patient, as ALLHAT authors advise, could well be the wrong first drug more than half of the time. Not stopping the wrong drug will lead to unnecessary multiple drug use.”
Laragh states that the most significant problem with the ALLHAT study is that it accepts a concept he believes is in error, “that all human hypertension is alike.” He writes, “There are two different types of hypertension, one dependent on too much salt and the other on too much action of the hormone renin in the blood. The appropriate first treatment is quite different, a diuretic in one case and an anti-renin drug in the other.”
Lawrence M. Resnick, MD, an American Journal of Hypertension editor for clinical and basic sciences and an endocrinologist, writes that “other reasonable medical conclusions” could have been drawn from the ALLHAT study. He believes that the same data would support a different conclusion --- that an angiotensin-converting enzyme inhibitor should be the drug of first choice--- because this class produced outcomes equal to those achieved with a diuretic but with a greater effect in lowering blood pressure itself. In addition, Resnick is concerned about widespread diuretic use because of side effects (reported in the ALLHAT paper) that are associated with increased mortality and morbidity over periods longer than those studied in the trial.
Jay I. Meltzer, MD, a nephrologist, makes some of the same points in his editorial: “ALLHAT’s results should have led to the conclusion that newer drugs save lives to at least the same extent as did the previously accepted [Sixth Joint National Committee report] gold standard, diuretics. No such conclusion was reached.”
He gives the opinion that inadequacies in the ALLHAT paper are due to a failure of peer review and a rush to judgment; he writes that reviewers were given only 48 hours to assess the study before it was published. “This study, ignoring the importance of its primary endpoints, but emphasizing soft secondary endpoints and changing the purpose of the study after it was completed, requires critical dissection by all concerned scientific disciplines, not a hurried acceptance. Conclusions based upon a study’s secondary endpoints, after failing support from the primary endpoints, may be used for hypotheses but cannot be relied upon for definitive treatment recommendations.”
Regardless of individual reactions to the new report and its treatment guidelines, the magnitude of the problem is clear: Nearly 50 million Americans (23 percent of the population) have hypertension. The need for appropriate, aggressive prevention and treatment strategies is almost overwhelming.