New Guidelines: "Normal" Blood Pressure Range Changes

May Is National High Blood Pressure Education Month

< May 20, 2003 >Millions of Americans who believe their blood pressure is normal may actually have "prehypertension," a condition considered to be a precursor to hypertension.

Recently, experts at the National Institutes of Health (NIH) issued new clinical practice guidelines for the prevention, detection, and treatment of high blood pressure.

The guidelines feature altered blood pressure categories, including a new "prehypertension" level which covers about 22 percent of adults or about 45 million Americans.

The new guidelines also streamline the steps by which doctors diagnose and treat patients, and new is the recommendation for the use of diuretics as part of the drug treatment plan for high blood pressure in most patients.

Prehypertension a Risk for Heart Disease

The guidelines were approved by the Coordinating Committee of the NHLBI's National High Blood Pressure Education Program (NHBPEP). Called "The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure," the guidelines are presented in the Journal of the American Medical Association (JAMA).

"Since 1997, much more has been learned about the risk of high blood pressure and the course of the disease," says NHLBI Director Dr. Claude Lenfant. "Americans' lifetime risk of developing hypertension is much greater than we'd thought. For instance, those who do not have hypertension at age 55 have a 90 percent risk of going on to develop the condition.

"We also now know that damage to arteries begins at fairly low blood pressure levels, those formerly considered normal and optimal," Dr. Lenfant says. "In fact, studies show that the risk of death from heart disease and stroke begins to rise at blood pressures as low as 115 over 75, and that it doubles for each 20 over 10 millimeters of mercury (mm Hg) increase. So the harm starts long before people get treatment."

Dr. Lenfant says, "Unless prevention steps are taken, stiffness and other damage to arteries worsen with age and make high blood pressure more and more difficult to treat. The new prehypertension category reflects this risk and, we hope, will prompt people to take preventive action early."

High blood pressure is a major risk factor for heart disease and the chief risk factor for stroke and heart failure, and also can lead to kidney damage. It affects about 50 million Americans, about one in four adults.

Treatment seeks to lower blood pressure to less than 140 mm Hg systolic and less than 90 mm Hg diastolic for most persons with hypertension (less than 130 systolic and less than 80 diastolic for those with diabetes and chronic kidney disease).

According to findigs from a national survey released in an NIH press statement, 70 percent of Americans are aware of their high blood pressure, 59 percent are being treated for it, and 34 percent of those with hypertension have it under control.

Those percentages represent a slight improvement over rates for 10 years ago, when 68 percent of Americans were aware of their high blood pressure, 54 percent were being treated for it, and 27 percent of those with hypertension had it under control.

Guidelines: Looking at the New Numbers

The new report changes the former blood pressure definitions to: normal, less than 120/less than 80 mm Hg; prehypertension, 120-139/80-89 mm Hg; stage 1 hypertension, 140-159/90-99 mm Hg; stage 2 hypertension, at or greater than 160/at or greater than 100 mm Hg.

The 1997 categories were optimal, normal, high-normal, and hypertension stages 1, 2, and 3.

The guidelines do not recommend drug therapy for those with prehypertension unless it is required by another condition, such as diabetes or chronic kidney disease. But the report advises them - and encourages those with normal blood pressures - to make any needed lifestyle changes.

Lifestyle changes include losing excess weight, becoming physically active, limiting alcoholic beverages, and following a heart-healthy eating plan, including cutting back on salt and other forms of sodium. The report also recommends that, for overall cardiovascular health, individuals quit smoking.

As in the 1997 guidelines, the new report recommends Americans follow the DASH  - Dietary Approaches to Stop Hypertension - eating plan, which is rich in vegetables, fruit, and nonfat dairy products. Clinical studies have shown that DASH significantly lowers blood pressure. The decreases are often comparable to those achieved with blood pressure-lowering medication.

The guidelines recommend use of a diuretic, either alone or in combination with another drug class, as part of the treatment plan in most patients. The report notes that even though many studies have found diuretics to be effective in preventing hypertension's cardiovascular complications, they are currently not being sufficiently used.

The guidelines also list other drug classes that have been shown to be effective in reducing hypertension's cardiovascular complications. Those considered to begin therapy include angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers, beta-blockers, and calcium channel blockers.

The report also gives the "compelling indications" - or high-risk conditions - for which such drugs are recommended as initial therapy.

According to the new report, most persons will need two, and at times three or more, medications to lower blood pressure to the desired level.

"The past six years have brought results from more than 30 clinical studies worldwide, many of which were funded by the NHLBI," said Dr. Aram V. Chobanian, dean of Boston University School of Medicine in MA and chair of the Joint National Committee that produced the new guidelines.

"These findings have been remarkably consistent in demonstrating the critical importance of lowering blood pressure, irrespective of age, gender, race, or socio-economic status.

"Though improved, the treatment and control rates are still too low," said Dr. Chobanian. "The new guidelines zero in on this problem, recommending factors that often lead to inadequate control such as not prescribing sufficient medication. The guidelines stress that most patients will need more than one drug to control their hypertension and that lifestyle measures are a crucial part of treatment.

"Another key factor is the need for clinicians to pay more attention to systolic blood pressure in those age 50 and older," says Dr. Chobanian. "From mid-life on, systolic hypertension is a more important cardiovascular risk factor than diastolic. It's also much more common and harder to control."

Always consult your physician for more information.

 Online Resources

(Our Organization is not responsible for the content of Internet sites.)

American Heart Association

American Society of Hypertension

Centers for Disease Control and Prevention (CDC)

DASH Eating Plan, NHLBI

Eat Five to Nine A Day, National Cancer Institute (NCI)

National Heart, Lung, and Blood Institute (NHLBI)

National Institutes of Health (NIH)

Your Guide to Lowering Blood Pressure, NHLBI

For more information on health and wellness, please visit health information modules on this Web site.

Even low-to-moderate intensity activities for as little as 30 minutes a day can be beneficial. These activities may include:

However, more vigorous aerobic activities, done three or four times a week for 30 to 60 minutes, are best for improving the fitness of the heart and lungs.

Regular, aerobic physical activity increases a person's capacity for exercise and plays a role in prevention of cardiovascular diseases.

Aerobic exercise may also help to lower blood pressure.

These activities may include:

Benefits from regular exercise or physical activity:

A daily exercise program may provide a way to share an activity with family and friends, while helping establish good heart-healthy habits.

Always consult your physician before starting an exercise program.

Tips for a Healthy Weight

Follow these nutrition tips for maintaining a healthy weight:

Remember - a calorie is a calorie. High-fat foods generally have more calories than foods that are high in carbohydrates or protein, but the best way to lose weight is to eat fewer calories than you burn each day.

Fruits, vegetables, and other foods that are low in fat and calories can also help reduce your risk of heart disease, stroke, and cancer.

Start your day off right by eating breakfast. Spruce up your breakfast - a banana or handful of berries will liven up your cereal, yogurt, waffles, or pancakes. Take a piece of fruit to munch on during your commute.

Use butter and margarine sparingly. Even better, switch to reduced-fat margarine or try jelly on your bread, bagels, and other baked goods.

Use "lite" or low-fat dairy products. You will still get the nutrients and taste but not the fat.

Use oils sparingly (try olive and canola oils). Bake chicken without the skin. Substitute a potato for french fries.

Choose the leanest cuts such as beef round, loin, sirloin, pork loin chops, turkey, chicken, and roasts. And if you cook it yourself, trim all visible fat and drain the grease.

Use oils sparingly (try olive and canola oils). Bake chicken without the skin.

Substitute low-fat or fat-free baked goods, cookies, and ice cream. Or, choose fruit. It tastes great, is filling, and provides energy.

Eat when you are hungry and stop when you are full. Take smaller portions. Never go back for seconds.

Typical restaurant servings are often twice the size of a single serving. When dining out or ordering in, ask for half of a serving or a "doggy bag." That way you will not be as full, and you can have some tomorrow.

Fast food does not have to be high in fat and calories. Try ordering a lean roast beef or grilled chicken sandwich. Keep the portions to regular and small.

Always consult your physician for more information.