As reported by the New Haven Register, October 27, 2008.

Blood Pressure Should Be Taken Often

By Abram Katz

Physicians can control blood pressure much better when patients take readings throughout the day, not just at the doctor’s office, according to a position paper to be published next month by the University of Connecticut Health Center.

Pressure can now be self-checked fairly easily with inexpensive devices that both inflate a sensing cuff and record readings, doctors said.

Series of readings taken before and after hypertension medication is taken give doctors more information about daily fluctuations, said Dr. William B. White, professor of medicine and chief of hypertension at the Calhoun Cardiology Center at UConn.

White is also co-author of the white paper on hypertension, which is scheduled for publication in the November Journal of Clinical Hypertension. The paper is appearing under auspices of the American Society of Hypertension.

Between 24 to 30 percent of the American population has hypertension at any given time, based on figures from the U.S. Centers on Disease Control and Prevention.

This statistic is worrisome to public health officials because hypertension raises the risk of heart attack, heart disease, stroke, kidney disease, and eye damage.

Blood pressure is the force with which blood pushes against walls of arterial vessels. The first number is the pressure while the heart is contracting, while the second is the pressure between beats. A normal pressure is in the neighborhood of 115 over 75. A reading of 140 over 90 is considered high.

Blood pressure fluctuates through the day, White said. A reading in a doctor’s office is merely a “snapshot,” which might be influenced by anxiety over being examined.

Pressure trends are usually more important than single readings, he said. For example, a doctor should be able to determine the patient’s blood pressure between doses of hypertensive medication.

“I had a patient who was a 70-year-old man who took three blood pressure medications. But he found upon awakening that his pressure was very high,” White said.

The man’s previous doctor was not impressed by his patient’s reading, White said.

“We fixed him up with a device that measured his blood pressure 180 times a day. It turned out that his blood pressure was too high 24 to 35 percent of the day,” he said.

White said he prescribed longer-acting and time-released drugs, increasing the duration of the normal period. Now physicians aim for normal pressure during at least 80 to 85 percent of a patient’s day.

“It’s time for doctors to use both patient blood pressure readings, plus 24-hour readings in order to find what the blood pressure is all the time, to avoid misdiagnosing the patient,” White said.

The American Heart Association has found the most meaningful data is gathered when a patient takes readings for a full week. Two readings are taken in the morning, before and after medication is taken, and two more at night. Readings are then averaged.

If the average comes out to 130 over 80, the patient is usually OK, White said.

Measuring blood pressure at home is becoming easier, he said. A device costing $50 to $100 should be able to automatically test and produce a reading to an accuracy of about 2 percent, he said.

The American Society of Hypertension’s formal recommendations call for one week of measurements per quarter, with one 24-hour reading. Better control of blood pressure reduces build up of atherosclerotic plaque, along with the risk of heart attack and stroke.