MAKING DIAGNOSIS FOR HYPERTENSIONThere is general agreement that optimal blood pressure is 120/80 or less. However, exactly what blood pressure constitutes hypertension is subject to some interpretation. In the past a diagnosis of hypertension was often based exclusively on diastolic blood pressure (the bottom number in the blood pressure reading). If your diastolic pressure was over 90, you had high blood pressure. It was felt that because the heart takes longer to rest than it does to beat, the diastolic measurement was more significant. However, more recent research has made it clear that an elevated diastolic pressure is no more hazardous than a high systolic reading – and the latter appears to be an even more accurate predictor of cardiovascular risk. The current consensus is that elevations in either systolic or diastolic blood pressure readings should be taken seriously. This is particularly true among older people, who may have dangerously high systolic readings while maintaining virtually normal diastolic blood pressure.According to current American Heart Association guidelines, hypertension is clinically defined as a systolic blood pressure greater than 140 or a diastolic pressure greater than 90. This echoes the recommendations of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC), a widely respected National Institutes of Health task force of physicians who are experts in hypertension and whose recommendations are approved by most major organizations. The JNC, which updates its recommendations periodically, published its sixth and latest report of guidelines in November 1997. The committee devised an updated system of diagnosis using both systolic and diastolic blood pressures to assess a patient’s health risk. The guidelines also recommend that clinicians specify other known risk factors, including smoking, immoderate drinking, and routine overeating. All of this information is then combined to determine the stage of risk for a specific patient. The higher the stage, the greater the patient’s risk of a heart attack or stroke.However, more recent research suggests that blood pressure readings for a diagnosis of hypertension might need to be adjusted downward. In June 1998, results of the Hypertension Optimal Treatment (HOT) trial, a five-year study involving almost 19,000 patients from26 countries, were published in The Lancet, one of the world’s leading medical journals. Researchers found that patients who were able to lower their systolic blood pressure to an average of 138.5 mm Hg and their diastolic blood pressure to an average of 82.6 had major reductions in heart attack and stroke risk. In early 1999, the World Health Organization and the International Society of Hypertension recommended that the upper limit for high normal blood pressure be lower, 130/85 (down from the JNC’s upper limit of 139/89). They based this on findings of the HOT trial and other studies showing that stroke and heart attack risk are dramatically reduced when diastolic blood pressure is less than 85.You may be thinking, “Why quibble over such small numbers? What’s the difference between 85 and 89?” According to an article published in the Journal of the American Medical Association in March 1999, a decrease in diastolic blood pressure of only 5 to 6 points lowers your risk for stroke 42 percent.*5/313/5*