WASHINGTON -- The number of Americans suffering from high blood pressure dropped an "unprecedented" 14 percent between 1980 and 1991 -- a sign that certain lifestyle changes have begun to work, federal health officials reported yesterday.
The National Heart, Lung and Blood Institute, part of the National Institutes of Health, said that the prevalence of high blood pressure, or hypertension, dipped from 58 million people in 1980 to 50 million in 1991.
Officials speculated that increasing attention to physical fitness, healthier diets -- especially lower sodium intake and reduced alcoholconsumption -- and smoking cessation could be responsible for the decline.
"People didn't start doing these things yesterday," said Dr. Claude Lenfant, director of the institute. "It's been going on for years -- and now we are seeing the results."
An estimated 2 million Americans annually develop high blood pressure, the most critical risk factor for stroke. Hypertension is also a major contributor to heart disease, the nation's No. 1 killer of both men and women, and to kidney failure.
The NIH called for a new national prevention campaign to target both the general population and individuals at high risk of developing hypertension, including blacks and those with a family history of high blood pressure, to lower the incidence even further.
That program would build on the continuing work of the National High Blood Pressure Education Program, a cooperative effort between the heart institute and several voluntary and professional health organizations that began in 1972.
"The complications caused by high blood pressure are insidious, progressive and costly," Dr. Lenfant said. "It is not enough to treat the condition. We need to help Americans avoid its development."
Blood pressure is the amount of force exerted by the blood againstthe walls of the arteries. It is expressed in two numbers, usually one above the other, such as 120 over 80.
The first number, the systolic pressure, represents the force used when the heart beats. The second number, the diastolic pressure, is the pressure within the arteries between heartbeats. Anything above 140 over 90 is considered high.
Even so-called "mild" hypertension, which ranges between 140 to 159 for the systolic pressure and 90 to 99 for the diastolic, is considered dangerous, and should not convey a sense of "complacency," officials said.
High blood pressure cannot be cured, but it can be controlled through proper treatment. Sometimes this can be done through weight loss, regular exercise and reducing alcohol, table salt and sodium, which is an ingredient in salt that is found in many packaged foods, baking soda and some antacids.
If these methods fail, it also can be controlled through the use of certain drugs. These include diuretics, or beta-blockers, which are usually prescribed first, or calcium antagonists, angiotensin converting enzyme inhibitors, alpha-receptor blockers and alpha-beta blockers, which are usually given if the other drugs do not work.