Feature Archive

The New Low for High Blood Pressure

Nearly a quarter of American adults just got diagnosed with a new disorder: prehypertension. Is your blood pressure low enough?

By Gina Shaw
WebMD Feature

Reviewed By Michael Smith

One night back in May, I went to sleep with perfectly normal blood pressure, an unremarkable 120/80. The next day, I woke up in a blood pressure danger zone. What happened? My blood pressure didn't spike overnight; instead, government officials issued revised blood pressure guidelines that included a new category: prehypertension.

Anyone with a systolic (top number) reading of 120 or over, or a diastolic (bottom) reading of 80 or over, now has prehypertension, which means we're at increased risk of heart disease and stroke.

Between those of us with newly-minted prehypertension (some 23% of the population), and people who have full-blown hypertension (at least another 25%), danger-zone blood pressure is an emerging epidemic in this country. Nearly half of all American adults over 18 are in one category or the other.

Are so many of us really so unhealthy? I'm only 36. I run three miles every other day. (Well, okay, sometimes I skip a day.) I almost never eat fried foods. I'm just one of thousands of people in their 30s, 40s and 50s who thought we were paragons of health until the new numbers were released. Are the doctors just trying to scare us?

A Wake-Up Call

"This is a wake-up call. We've changed what normal is, because we now know that blood pressure in the prehypertension range is not normal," says Sheldon Sheps, MD, medical editor of MayoClinic.com's High Blood Pressure Center. He served on the committee that drafted the new guidelines.

"There is increasing evidence of the relationship between an elevated blood pressure and future problems with heart attack and stroke. With each level of increase in pressure, you get increased risk," he tells WebMD. Consider these startling statistics:

  • Starting as low as 115/75, the risk of heart attack and stroke doubles for every 20-point jump in systolic blood pressure or every 10-point rise in diastolic blood pressure.
  • People with blood pressure levels between 120/80 and 140/90 - levels once considered normal - have twice the risk of heart disease as those with low blood pressure.
  • And people with blood pressure above 140/90 - the definition of high blood pressure -have four times the risk of heart disease as people with low blood pressure.

"We've also learned that people age 55 and older, who currently have normal blood pressure, have a 90% risk of developing high blood pressure down the road," says Aram Chobanian, MD, Dean of Boston University School of Medicine, who chaired the guidelines committee.

Next: The new disorder of "healthy" adults.

Prehypertension

"We have a lot of concern about this rise in blood pressure over the course of our lifetimes, and to try to prevent that from happening, we have identified a 'prehypertension' group in which lifestyle changes can make a difference," Chobanian says.

But if so many people are already likely to go on to develop high blood pressure, can we really avoid it? Maybe high blood pressure is just an inevitable consequence of aging. Not so, says Chobanian.

"There are populations in the world where age-related rises in blood pressure are minimal. In areas of Mexico, certain areas of the South Pacific, and other parts of the world with very low salt intake, there's not anywhere near the age-related rise in blood pressure that we see in the United States."

The Name of the Game: Prevention

So if rising blood pressure and aging don't -- or shouldn't -- go hand in hand, what should the millions of us who now have prehypertension do about it? The good news: we shouldn't be looking for a new pill. "Unless you have diabetes or kidney disease, people with prehypertension don't need to be on medication," says Sheps.

That's also the bad news. Preventing high blood pressure means lifestyle changes, which is usually harder than popping a pill. Number one on the blood pressure reduction hit parade: preventing or treating obesity. As our pants sizes get smaller, so do our blood pressure numbers. Of course, the opposite is true as well. With our nation on a supersizing binge and a growing percentage of adults and children becoming overweight or obese, it's no surprise that rates of high blood pressure have skyrocketed as well.

Next: A diet as good as medicine.

The DASH Diet

You can get your weight down by any number of methods, but ultimately, staying healthy means choosing a plan you can live with long-term. Of the trendy high-protein, low-carb plans like Atkins and South Beach, Sheps says, "If you want to try them to get a jump-start on weight loss, go ahead for a month or two months. That's about all people can stand before they get bored to tears.

"But for life, the diet you need to be on for life is the DASH diet, which is not specifically designed for weight loss. The Holy Grail is a healthier lifestyle and we know from untold numbers of studies that if you follow a diet rich in fruits and vegetables and low in fat, you'll live longer and better."

High in whole grains, fruits, and vegetables, and low in total saturated fats, DASH (Dietary Approaches to Stop Hypertension) has been found to be as effective in reducing blood pressure as blood pressure medication. "It's not clear what it is about DASH that works, but it's high in potassium and calcium and low in saturated fat and sodium," says Chobanian. "It's a sensible diet that you can realistically follow for the rest of your life."

Studies have also shown that DASH is even more effective in controlling weight and reducing blood pressure when combined with a regular exercise program. If you can't fit in the newly-recommended one hour of physical activity a day, half an hour daily still beats never breaking a sweat.

Ultimately, say experts, those of us with prehypertension need to be more aware of our changing blood pressure rates. Sheps suggests monitoring your blood pressure on your own between doctor's visits, using a home blood pressure device. "Just make sure the cuff size is appropriate," he says. "It needs to cover at least 80% of the circumference of the arm."

Putting the brakes on the high blood pressure epidemic won't be easy. "It's always an uphill battle to get people to change their lifestyles," says Chobanian. Yet these days, when half of American adults are at risk for heart attack or stroke because of their blood pressure, doctors say it's time for a major public health effort.

Published Sept. 11, 2003


SOURCES: Sheldon Sheps, MD, medical editor of MayoClinic.com's High Blood Pressure Center and former chair of the Division of Hypertension in the Department of Internal Medicine at the Mayo Clinic. Aram Chobanian, MD, Provost of the medical campus and Dean of Boston University School of Medicine.

©1996-2005 WebMD Inc. All rights reserved.


Last Editorial Review: 1/31/2005 6:47:50 AM



    STAY INFORMED

    Get the Latest health and medical information delivered direct to your inbox!