Controlling blood pressure may lengthen life and keep heart disease away.

That may sound familiar. Now, researchers are driving the message home.

Men and women with normal blood pressure at age 50 lived five more years than those with higher blood pressure. They also avoided heart disease for a longer time.

So say Oscar Franco, MD, DSc, and colleagues in the journal Hypertension. Franco is a scientific researcher in the University of Rotterdam's public health department.

Why Blood Pressure Matters

You could have high blood pressure and not know it. Lots of people do.

About one in three U.S. adults has high blood pressure. But nearly a third of them don't know it, says the American Heart Association (AHA).

Blacks are especially hit hard. More than 40 percent of black U.S. adults have high blood pressure. It often starts younger and is more severe for them compared with other races, says the AHA.

High blood pressure raises the risk of heart disease, stroke, heart failure, and kidney failure.

But the complications caused by high blood pressure can be avoided by treating the disease. A healthy diet, stress control, and an active, nonsmoking lifestyle are important. Some people may also need help from medicine.

Read WebMD's "High Blood Pressure: The Invisible Risk"

Getting Tested

High blood pressure does its damage quietly. It's easily flagged by a quick, painless test.

The test yields two numbers. The "top" number is called systolic blood pressure, which measures the pressure on blood vessel walls when the heart beats. Systolic pressure may be more important as one begins to age. The association between complications due to high blood pressure and high blood pressure is continuous — the higher the blood pressure, the higher the risk of complications.

The "bottom" number is diastolic blood pressure — the pressure on blood vessel walls in between beats.

The AHA's standards for adults are:

— Normal: Less than 120/80

— Borderline (prehypertension): 120-139/80-89

— High: 140/90 or higher

Read WebMD's "Dark Chocolate May Lower Blood Pressure"

Latest Blood Pressure Study

Franco studied data from more than 3,100 people who were 50 years old.

They were tracked for up to 46 years. They got medical checkups every other year as part of the large Framingham Heart Study.

Their other health records were also noted. So were hospitalizations and death certificates.

Cholesterol and physical activity levels weren't always known. Other risk factors were considered. Those included smoking status, age, sex, body mass index (BMI), and education.

Less Time With Heart Disease

People with normal blood pressure didn't just live longer. They also spent fewer years with poor heart health.

Men with normal blood pressure lived seven more years without heart disease than those with high blood pressure. They spent two fewer years of their life with heart disease.

Women had similar benefits, say the researchers.

As blood pressure levels rose above normal, so did the risk of heart disease, heart attack, and stroke, they write.

Read WebMD's "5 Steps to a Healthier Heart"

Then and Now

The data were gathered decades ago, in the 1950s and 1960s.

Back then, blood pressure control in the U.S. was "poor," say the researchers.

Times have changed. Still, the researchers say the study shows what can happen if high blood pressure doesn't get appropriate treatment.

More studies should be done of people who are treated, they say.

'Solid Evidence'

The findings are "solid evidence" about the life-lengthening, heart-protecting benefits of curbing high blood pressure. So says Athanase Benetos, MD, PhD, in a journal editorial.

Benetos is an internal medicine and geriatrics professor at France's Centre de Gériatrie CHU-Nancy and INSERM U684.

Read WebMD's "Strategies to Prevent and Control High Blood Pressure"

To-Do List

Your health care provider can help you get started on the right path. The first step: Get tested. Learn your blood pressure numbers, and take it from there.

By Miranda Hitti, reviewed by Brunilda Nazario, MD

SOURCES: Franco, O. Hypertension, June 27, 2005, Online First. Benetos, A. Hypertension June 27, 2005, Online First. American Heart Association: "High Blood Pressure." American Heart Association: "A Special Message for African Americans." American Heart Association: "Am I at Risk?" News release, American Heart Association.