Under the revisions, 45 million Americans who had previously thought they had normal blood pressure now have a condition called "prehypertension."
Several pages of the May 21 issue of the Journal of the American Medical Association are devoted to the guidelines. But three lengthy articles in the May issue of the American Journal of Hypertension assail the study on which the guidelines are largely based.
Probably the biggest change in the so-called JNC 7 guidelines -- Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure -- is a new classification for hypertension, or high blood pressure.
Now, any reading under 120/80 is considered normal. However, anything between 120/80 and 139/89 is now considered "prehypertensive; previously that was considered within the normal range. Anything between 139/89 and 159/99 is considered "Stage 1 hypertension." And anything topping 160/100 is "Stage 2 hypertension."
Ed Roccella is coordinator of the National High Blood Pressure Education Program, part of the National Heart, Lung, and Blood Institute, which issued the new guidelines.
"Since the publication of JNC 6, there have been more than 30 trials, so we need to apply that data so that clinicians and the public can use this information," he explains.
"Sixty million Americans have high blood pressure. Another 45 million Americans have prehypertension," he adds. "Cardiovascular disease is the number one killer for men and women. We spend more than $324 billion a year on treating cardiovascular disease. If we just prevent 10 percent, that would be a substantial savings."
Some experts are troubled by certain aspects of the new guidelines.
One recommendation is fairly benign and even welcomed -- that patients with full-blown hypertension take two medications from the beginning of treatment, rather than starting on one and waiting to see what happens before adding another drug.
"For the first time, they are quite strongly recommending that treatment of hypertension start with a combination of two drugs if the baseline blood pressure is at last 160/100," says Dr. Michael Weber, professor of medicine at State University of New York Downstate Medical Center in New York City, and past president of the American Society of Hypertension (ASH). "They're almost certainly going to need two drugs anyway. So why not start that way and get there more quickly. There's a certain logic to it."
The real controversy, however, is likely to come from another recommendation: That the first-line treatment for individuals who don't need the two-drug therapy should be thiazide-type diuretics, except for people with certain high-risk conditions such as diabetes or renal complications.
Roccella says that a diuretic, "when it's available and it works, should be used. It's inexpensive and it's been shown in clinical trials tobe effective."
But Weber says, "There's no real evidence to support it [the diuretic guideline]."
"The reason for that [particular guideline] and the reason they're issuing the guidelines right now is that the people who wrote these guidelines leaned heavily on data from ALLHAT and there was an enormous amount of controversy over that trial," says Dr. Thomas Giles, president-elect of the American Society of Hypertension.
ALLHAT refers to the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial, which was published late last year, also in the Journal of the American Medical Association.
"ALLHAT came in for a great deal of criticism and many people, myself included, believe that ALLHAT did not show that there was any special benefit to diuretics," Weber says.
Diuretics may work well for certain groups of people, such as African-Americans and elderly patients, Weber points out. But white patients and young patients are more likely to benefit from ACE inhibitors or angiotensin receptor blockers.
Just because the guidelines have been issued doesn't mean doctors are compelled to follow them. In fact, critics aren't worried so much about what doctors will do. They're worried about what health plans and patients might do.
"What we are a bit concerned about is that some of the health plans and insurance plans that are very anxious to save money will say we're not going to cover it or we'll cover it but you have to write a justification," Weber says. "It's such a pain in the neck for doctors to jump through all those hoops. Many of them will just give in and go the path of least resistance."
Weber also predicts that the National Heart, Lung, and Blood Institute may aggressively try to spread the diuretics message. "That, to me, is very troubling because patients are going to come in and ask, 'Why are you giving me more expensive drugs' " instead of diuretics? he says.
Trying to save the country money may be a worthy goal, Weber adds, but you need to show that cost-savings are not going to have added costs in terms of people's health.
"If I have a 28-year-old young white male with hypertension and giving a diuretic to such a person is not going to work, the fact that it's cheap doesn't help me," Weber says.