High blood pressure redefined for first time in 14 years: 130 is the new high American Heart Association/American College of Cardiology Guidelines. November 13, 2017 High blood pressure is now defined as readings of 130 mm Hg and higher for the systolic blood pressure measurement, or readings of 80 and higher for the diastolic measurement. That is a change from the old definition of 140/90 and higher, reflecting complications that can occur at those lower numbers. In the first update to comprehensive U.S. guidelines on blood pressure detection and treatment since 2003, the category of prehypertension is eliminated. While about 14 percent more people will be diagnosed with high blood pressure and counseled about lifestyle changes, there will only be a small increase in those who will be prescribed medication. By lowering the definition of high blood pressure, the guidelines recommend earlier intervention to prevent further increases in blood pressure and the complications of hypertension.