It was a meeting full of mixed messages. The panel of experts at the New York Academy of Sciences began the discussion with disturbing statistics. High blood pressure is so "out of control" that 65 million Americans have it. The prevalence has been increasing rapidly--up from 50 million in 2002. But only 58% of Americans with hypertension receive treatment; and nearly half of those on drug therapy do not have their blood pressure controlled to recommended levels. What's more, uncontrolled blood pressure is associated with increased risk of stroke, heart attacks, organ damage and even dementia.
But as the meeting wore on, things changed radically with the last two panelists saying that there is too much emphasis on blood pressure (BP). What's more, most cardiac "events" [stroke, heart attack, angina, etc.] occur in people without hypertension, said Michael H. Alderman, MD, Albert Einstein College of Medicine, Bronx, New York. It is not a disease, as hypertension is often portrayed, he explained, it is just one of many factors that puts a person at risk for a heart attack or stroke.
This meeting, held last month in New York City, was aimed at medical reporters who were provided with background information for the American Society of Hypertension's upcoming annual conference. Novartis Pharmaceuticals Corporation sponsored the event entitled, "Looking Toward the JNC-8: The Future of Hypertension Treatment Guidelines." The JNC refers to the Joint National Committee, which updates its recommendations every few years. Most recently, the 2003 JNC-7 report alerted Americans to the existence of a new condition called prehypertension. BP within the range of 120/80 to 139/89 mm Hg (millimeters of mercury) used to be normal; now it's prehypertension.
Small wonder that the number of Americans with hypertension is increasing rapidly given the fact that the JNC changes the definition of normal every ten or so years, putting more and more people into the hypertensive category. The JNC-7 guidelines came in for some criticism from Dr. Alderman. The treatment goals were inconsistent, and it was unclear about what doctors should do about prehypertension. He wants doctors "to get beyond 140/90 or 120/80 that define our actions," and instead look at their patients' total cardiovascular risk, such as high cholesterol, glucose intolerance, cigarette smoking, and left ventricular hypertrophy (a sign of prolonged strain on the heart, usually due to high BP).
The people at highest risk are those with cerebrovascular disease, diabetes, kidney disease and heart disease, whether or not their BP is within the normal range. "The systolic, or upper number in BP measurement should be the focus of treatment," said Dr. Alderman, "because it's a better measure of cardiac risk in people over 50." The commendable aspects of the JNC-7 were also discussed. For example, the 2003 guidelines drew heavily from a newly published major trial that found the older, least expensive antihypertensive drug class, called thiazide-type diuretics, should be the first choice in most cases. The same trial found that this drug is often not enough, and most people with high BP must take one or more additional drugs.
Matthew R. Weir, MD, University of Maryland School of Medicine, Baltimore, elaborated on this point. The multiple-drug regimen should be tailored to the individual, according to Dr. Weir, who said the additional drugs could be an ACE inhibitor (some brand names: Lotensin, Capoten, etc.), an angiotensin receptor blocker (Cozaar, Benicar, etc.), and/or a medication from other drug classes that treat hypertension. The optimal combinations have not been identified.
Although many more trials are now looking at multi-drug combinations, observed Dr. Weir, they tend to last only five years and have high-risk participants. "These trials are designed to find something bad [heart attacks, strokes, etc.] within a five-year period," he said, explaining why high-risk people are selected as participants. Yet Dr. Weir observed that these drugs will be taken for decades--often by people who are not at the same high risk. (In other words, the long-term health effects are unknown for many people on lifelong drug therapy.) After the drug combination is chosen according to the individual's entire risk profile, Dr. Weir advocates a complete reassessment after five years of treatment.
The meeting's emphasis was clearly on drugs rather than the non-pharmacological approaches. Studies show that lifestyle changes will make only small reductions in BP, according to Dr. Alderman. His POWERPoint slide summarized the range of systolic BP reductions, that studies found with each approach: weight reduction (5 to 20 mm Hg with weight loss of about 22 pounds); sodium reduction (2 to 8 mm Hg); physical activity (4 to 9 mm Hg); moderation of alcohol consumption (2 to 4 mm Hg); and a diet high in fruits and vegetables and a reduced intake of saturated and total fat (8 to 14 mm Hg).
While these lifestyle changes together can make significant reductions in BP, Dr. Alderman said that studies have failed to demonstrate that they can reduce heart attack, stroke, or death. "Yet we do know a lot about how drug therapy can lower the risk of cardiovascular events," he said.
Nothing was said about the harms of BP drugs, such as impotence and impaired thinking. Dr. Alderman, however, did mention the studies that showed the reductions in cardiac deaths by drug therapy are offset by an increase in overall deaths. This indicates that some deaths are caused by the drugs. And Dr. Weir acknowledged that older people taking multiple drugs for HBP are also likely to be taking several additional prescription drugs for other ailments. This multiplies the possibilities for adverse interactions.
While some doctors think these drugs are so important that just about every older adult should be on more than one, Dr. Alderman cautioned, "Our assessment might not be the same as the patient's. Some patients will say, 'I will pay the price for all these drugs, even if it only cuts my risk of 1/4 of 1%,' but others will say, 'don't bother me, there are more problems in this world [than high BP]' and that's reasonable." He advocates discussing the risk of developing a heart problem or a recurrence with patients along with the odds of benefiting from drug therapy. "A 30% reduction in risk [offered by the drugs] doesn't mean much if a person has a very small risk [for a heart attack or stroke], but it does if a person has a high risk."
Dr. Weir, who felt so strongly that hypertension should be de-emphasized that he would not utter the word at the beginning of his presentation, ended it by saying, "All of us would prefer to have lower BP." The population studies show that this makes sense, he continued, but we don't have the evidence to show that this is advisable for everyone.
In summary, the meeting's message was that hypertension should no longer be the entire focus in the prevention of heart attacks and strokes. Rather, a person's other risks for heart disease should also be considered. And treatment decisions, including the decision of whether to treat at all, would be based on an individual's entire risk profile.
COPYRIGHT 2005 Center for Medical Consumers, Inc.
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