New Evidence Suggests Increased Importance for Systolic Blood Pressure

New York, NY
April 15, 2000

According to the National Kidney Foundation (NKF), new evidence from a Framingham Heart Study finds that the top number in a blood pressure reading, called the systolic blood pressure, may not have been getting enough attention. Current treatment strategies have focused more on lowering the bottom number in a patient’s blood pressure reading, called the diastolic pressure.

The Framingham researchers reported that systolic blood pressure, far more than diastolic pressure, identifies patients with high blood pressure, determines their blood pressure stage and identifies the need for treatment. They found that systolic blood pressure alone correctly classified the blood pressure stage in about 96 percent of patients, while diastolic pressure alone classified only 68 percent of patients correctly. Among patients over age 60, systolic pressure alone correctly classified 99 percent of patients, whereas diastolic pressure alone correctly classified only 47 percent. The researchers concluded that paying more attention to systolic blood pressure may be important, especially in the elderly, who tend to have higher systolic blood pressures and lower diastolic blood pressures.

The top number in your blood pressure reading (the systolic pressure) measures the force blood exerts on the artery walls when the heart beats. The lower number (the diastolic pressure) measures the force on the arteries between heartbeats. High blood pressure is diagnosed when the systolic blood pressure is consistently 140 or higher or the diastolic blood pressure stays at 90 or higher.

According to the National Kidney Foundation, high blood pressure—one of the leading causes of kidney failure in the U.S.—generally has no symptoms. In order to find out if you have high blood pressure, you must have a blood pressure measurement. Blood pressures that are consistently 140/90 or higher are considered elevated. About 50 million Americans have elevated blood pressure, but of these, only 68 percent are aware of their condition, 54 percent are being treated, and only 27 percent have their high blood pressure under control.

Because uncontrolled high blood pressure can lead to serious complications like kidney failure, heart attacks and strokes, the National Kidney Foundation recommends that all Americans have their blood pressure checked. The risk of having these complications can be reduced greatly when high blood pressure is controlled.

If high blood pressure is mild, or Stage 1 (systolic pressure 140 to 159), you may be able to reduce it with lifestyle changes, such as losing weight, if you are too heavy, and exercising regularly. If systolic blood pressure is 160 or higher, one or more high blood pressure medications may be needed to control it. However, lifestyle modifications can help to lower the dose of medications needed. If you have high blood pressure, make sure to follow your treatment plan. For more information about high blood pressure, contact the National Kidney Foundation at (800) 622-9010.