BP of 150/90 new normal for people over 60
People over 60 can have a higher blood pressure than previously recommended before starting treatment to lower it, the guidelines said.
Experts also recommend that diabetes and kidney patients younger than 60 be treated at the same point as everyone else that age, when their blood pressure exceeds 140/90.
People with those chronic conditions, until now, have been prescribed medication when their blood pressure reading topped 130/80, 'Health Day' reported.
However, the definition of high blood pressure - anything above 140/90 - remains the same under the new guidelines.
Blood pressure is the force exerted on the inner walls of blood vessels as the heart pumps blood to all parts of the body.
The upper reading, known as the systolic pressure, measures that force as the heart contracts and pushes blood out of its chambers.
The lower reading, known as diastolic pressure, measures that force as the heart relaxes between contractions. Adult blood pressure is considered normal at 120/80.
High blood pressure affects about 1 in 3 US adults, or around 68 million.
The guidelines author Dr Paul James, head of the department of family medicine at the University of Iowa Carver College of Medicine, said the recommendations are based on clinical evidence showing that stricter guidelines provided no additional benefit to patients.
The US National Heart, Lung, and Blood Institute, that commissioned the Eighth Joint National Committee published an update to the last set of high blood pressure guidelines in the Journal of the American Medical Association.