The American Heart Association has changed the definition of hypertension for the first time in 14 years, moving the number from the old standard of 140/90 to the newly revised 130/80.
He said a diagnosis of the new high blood pressure does not necessarily mean a person needs to take medication, but that "it's a yellow light that you need to be lowering your blood pressure, mainly with non-drug approaches".
The updated guidelines were presented at the AHA's Scientific Sessions in Anaheim, California, on November 13 and published by the AHA and the American College of Cardiology.
The new guidelines from the AHA mean that almost half of all American adults - 46 percent - suffer from hypertension. However, there will only be a small increase in the number of US adults who will require antihypertensive medication, authors said.
That's a 14 percent increase from the previous guidelines, under which 72.2 million Americans (32 percent of adults) were considered to have high blood pressure. Blood pressure levels should be based on an average of two to three readings on at least two different occasions, the authors said. The top number is known as the systolic rate, measuring the pressure on your blood vessels when the heart beats.
The new guidelines incorporate data from the Systolic Blood Pressure Intervention Trial (SPRINT), which was a large, randomized controlled trial created to assess the impact of more aggressive versus standard blood pressure goals on hard cardiovascular outcomes.
The top number in a blood pressure reading refers to the amount of pressure in your arteries during contraction of your heart muscle.
"You've already doubled your risk of cardiovascular complications compared to those with a normal level of blood pressure", he said.
We need to send the message that yes, you are at increased risk and these are the things you should be doing, said Whelton, chair of global public health at Tulane University in New Orleans. One in five may need medication.
The new goal strikes "an appropriate balance between efficacy... and safety", for those who will be asked to take more medications that can have side effects such as dizziness and falling, said Bob Carey, vice-chair of the guideline committee and a professor of medicine and dean emeritus at the University of Virginia Health System School of Medicine. Hypertension, where the force of blood pushing against blood vessel walls is elevated, is considered the second-largest cause of preventable heart disease after smoking.
Under the older, higher target, 32% of adults in the USA had hypertension.
Instead, the guideline, published in the AHA's journal Hypertension, emphasizes that doctors need to focus on a whole framework of healthier lifestyle changes for patients.
Ferdinand said he hopes the new guidelines will push clinicians to treat patients earlier on, which could reduce the number of cardiac-related deaths, specifically heart attack and stokes. "Risk is already going up as you get into your 40s". Home readings can also identify "masked hypertension", when pressure is normal in a medical setting but elevated at home, thus necessitating treatment with lifestyle and possibly medications.
While people may be confused by the change, the heart experts said three years of reviewing the research showed that much fewer people die if high blood pressure is treated earlier.