For many years people have been told that their blood pressure was either normal or too high. Too high (high blood pressure or hypertension) was, and still is, defined as a systolic pressure of 140 mm Hg or greater and/or a diastolic blood pressure of 90 mm Hg or higher. People with a normal blood pressure presumed they had one less thing to worry about.
In 2003 a group of experts was assembled and given such a long name, the Joint National Commission on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, that their conclusions must be considered important. They formulated a new category of blood pressure, termed prehypertension, for people with systolic pressures between 120 and 139 mm Hg or diastolic pressures between 80 and 89 mm Hg.
The Commission also redefined normal blood pressure as a systolic pressure less than 120 mm Hg and a diastolic pressure less than 80 mm Hg. The category of prehypertension was established because available evidence indicated that such people were quite likely to develop real hypertension in the future.
A recent report from the Medical University of South Carolina described the not-surprising finding that prehypertension carries a 32 percent increased risk of heart attack, stroke, and heart failure compared with those whose blood pressure is normal. And the increased risk was even greater (79 percent) in those who had an additional risk factor like a high cholesterol level. The Commission recommended lifestyle measures, such as weight loss, exercise, and reduced salt intake, for people with prehypertension. Medication is recommended only for those who also have diabetes or kidney disease, for whom even lower blood pressures are the target.
Though I agree with these new definitions by the Joint Commission, the bottom line is that all the definitions are quite arbitrary and useful only for making decisions on treatment and for studies on the risks of different blood pressure levels. The cardiovascular risks of blood pressure grow continuously with rising blood pressure.
No matter what your blood pressure is, you?d be better off if it were lower.
