Chicago, IL - New national guidelines, known as the Seventh Report of the Joint National Committee (JNC) on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7), recommend a more aggressive approach to detecting and treating hypertension, including the introduction of a new "prehypertension" classification and a reminder that in patients older than 50, systolic blood pressure should be the focus of treatment.
The new report, published online today at JAMA Express, was also released this morning at a news conference held by the National Heart, Lung, and Blood Institute[1]. This first report, the authors say, is meant as a "succinct practical guide"; a more comprehensive report, "which will provide a broader discussion and justification for the current recommendations," is expected to be published this summer in the American Heart Association journal Hypertension, according to a release from the AHA
Corresponding author for the writing group was Dr Edward J Roccella (NHLBI).
Keeping it simple
The National High Blood Pressure Education Program Coordinating Committee, administered by NHLBI, is a coalition of 39 major professional, public, and voluntary organizations and seven federal agencies. The committee last issued guidelines in 1997[2].
The decision to appoint a new committee and issue new guidelines now was based on four factors, the authors write: "publication of many new hypertension observational studies and clinical trials; need for a new, clear, and concise guideline that would be useful to clinicians; need to simplify the classification of BP; and a clear recognition that JNC reports were not being used to their maximum benefit."
The "key messages" of the new guidelines:
In persons older than 50 years, the authors stress that systolic blood pressure of more than 140 mm Hg is a "much more important" risk factor than diastolic BP.
The risk of CVD, beginning at 115/75 mm Hg, doubles with each increment of 20/10 mm Hg; individuals who are normotensive at 55 years of age have a 90% lifetime risk for developing hypertension.
Individuals with a systolic BP of 120 to 139 mm Hg or a diastolic BP of 80 to 89 mm Hg should be considered as "prehypertensive," reflecting an increased risk of future hypertension and requiring health-promoting lifestyle modifications to prevent CVD. Those with BPs in the 130/80-to-139/89-mm-Hg range have twice the risk of hypertension as those with lower values, they note. "Before JNC 7, the definitions were more complicated and perhaps misleading," NHBLI Director Dr Claude Lenfant writes in a press release from AHA. "For example, the older terms 'high-normal' and 'borderline' high blood pressure suggested to some a lack of importance." (Lenfant wrote an editorial to accompany the full publication in Hypertension.) Stage 2 and stage 3 hypertension have been combined in the new classification
Thiazide-type diuretics should be used in drug treatment for most patients with uncomplicated hypertension, either alone or in combination with drugs from other classes. In trials including ALLHAT, they write, "diuretics have been virtually unsurpassed in preventing the cardiovascular complications of hypertension. The exception is the Second Australia National Blood Pressure trial, which reported slightly better outcomes in white men with a regimen that began with an ACE inhibitor compared with one starting with a diuretic," the authors say. "Diuretics enhance the antihypertensive efficacy of multidrug regimens, can be useful in achieving BP control, and are more affordable than other antihypertensive agents." Certain high-risk conditions, including post-MI and chronic kidney disease, are "compelling" indications for the initial use of other antihypertensive drug classes, they note.
Two or more antihypertensive drugs will be required to control hypertension to goal in most patientsthat is, to under 140/90 mm Hg, or less than 130/80 mm Hg for patients with diabetes or chronic kidney disease.
If blood pressure is more than 20/10 mm Hg above these targets, physicians should consider initiating therapy with two agents, one of which should usually be a thiazide-type diuretic.
The authors also emphasize, however, the role of patients in controlling their own BP. "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 potential motivator."
Finally, they write, "in presenting these guidelines, the committee recognizes that the responsible physician's judgment remains paramount."
On a larger scale, they point out that public health approaches provide the opportunity to lower the BP of a population, including reducing the calories, saturated fat, and salt in processed foods and increasing community and school-based opportunities for physical activity. These initiatives become especially critical as obesity reaches epidemic proportions in the US. Currently, they note, 122 million adults are overweight or obese, contributing to the rise in BP and related conditions.
"These public health approaches can provide an attractive opportunity to interrupt and prevent the continuing costly cycle of managing hypertension and its complications."
The will to act
In an accompanying editorial[3], Dr Thomas E Kottke (CardioVision 2020, Olmstead County, MN) and colleagues write that while the new JNC 7 report documents ways that "the burden of hypertension can be decreased," it 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%, they write. Control rates are "stagnant" at 34%, far short of the Healthy People 2010 goal of 50%. "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, but this requires commitment to the task, they write. Given the technologies are there to detect, treat, and control hypertension, they question the "will to succeed, which requires devoting the resources, organizing the treatment systems, and creating the environments that allow patients and clinicians to cross the hypertension quality chasm."
Hypertension is only one manifestation of what might be called "lifestyle syndrome," a cluster of diseases arising from ingesting too many calories, saturated fat, sodium, and alcohol and using tobacco or being exposed to tobacco smoke, they say. The tools outlined in JNC 7, provided they are implemented, could also limit other conditions arising from lifestyle syndrome, including cardiovascular disease, cancer, osteoarthritis, and type 2 diabetes.
"Action that leads to control of hypertension and reduces the burden of disease must be the criterion for success," Kottke et al conclude. "Clearly action to control blood pressure is needed now and is a challenge that all must accept."
Heartwire from Medscape © 2003
Cite this: New JNC 7 hypertension guidelines released - Medscape - May 14, 2003.
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