A significant difference in reading systolic or upper blood pressure between the two arms could be a warning sign of a future heart attack or stroke, according to a new meta-analysis of 24 global studies published Monday in the journal Hypertension.
“Patients who need a blood pressure check should now expect it to be checked in both arms at least once,” said lead author Dr. Chris Clark, a clinical lecturer at the University of Exeter Medical School in the United Kingdom. , in a statement. .
Blood pressure is measured in millimeter units of mercury (abbreviated as mmHg), which consists of two numbers – an upper or systolic reading that represents the maximum amount of pressure in your arteries and a lower or diastolic reading that shows the pressure in the arteries when the heart muscle he is resting between beatings.
The new study found that for every degree of difference between the two arms of more than 10 millimeters of mercury, the risk of having new angina (chest pain), a heart attack or stroke increased by 1% in the next decade.
The results of the study indicate that differences of more than 5 millimeters of mercury between the two arms “predict all-cause mortality, cardiovascular mortality and cardiovascular events.”
“We’ve known for a long time that a difference in blood pressure between the two arms is related to poorer health outcomes,” Clark said.
“This study tells us that the greater the difference in blood pressure between the arms, the greater the cardiovascular risk, so it is really essential to measure both arms to determine which patients may be at significantly higher risk,” he said. Clark.
The key systolic differences
A difference of 10 millimeters of mercury or less between the arms is considered normal by the AHA and is not a cause for concern. However, higher readings between the two arms could be a sign of narrowing or stiffening of the arteries, which can affect blood flow.
Unlike the guidelines in USA, those in both the United Kingdom and the European Union recognize “a systolic difference of 15 mmHg or greater between the two arms as an indicative threshold for additional cardiovascular risk,” the study said.
The co-author of the research, Victor Aboyans, a professor and head of the cardiology department at Dupuytren University Hospital in Limoges, France, said the study shows that international guidelines should be re-evaluated.
“We believe that a difference of 10 mmHg can now reasonably be considered an upper limit of normal for inter-arm systolic blood pressure, when both arms are measured in order during routine clinical appointments,” Aboyans said in a statement. statement.
This information should be incorporated into future guidelines and clinical practice in cardiovascular risk assessment. It would mean more people would be considered for a treatment that could reduce their risk of heart attack, stroke and death, Aboyans added.
In addition, health practitioners should measure blood pressure in both arms at checkups, the report said. Although international guidelines currently recommend this practice, it is “widely ignored”.
“While international guidelines currently recommend doing so, it only happens about half the time, best, usually because of time constraints,” Clark said.
“Checking one arm, then the other with a commonly used blood pressure monitor, is inexpensive and can be performed in any medical setting, without the need for additional or expensive equipment,” Clark said. “Our research shows that the little extra time needed to measure both arms could save lives.”
Take your own blood pressure
Anyone with blood pressure issues should monitor it at home and keep a reading log, the AHA suggests.
The AHA says to take blood pressure readings at the same time each day, such as morning or evening. Follow these steps to make sure you get a correct reading:
Do not smoke, drink caffeinated beverages or exercise for at least 30 minutes before measuring your blood pressure. Go to the bathroom and empty your bladder.
Sit with your back straight and leaning, which means sitting in a hard-backed chair at a desk or table, not a couch.
“The legs should be flat on the floor and the legs should not be crossed. The arm should be supported on a flat surface (such as a table) with the upper arm at the level of the heart,” the AHA recommends.
Lift your sleeve – do not take the measurement on your clothes. Stay there for at least five minutes of quiet rest before starting any measurement.
Follow the illustrations on blood pressure – a key step is to make sure the bottom of the cuff is placed directly above the elbow.
Do more reading and record the results. “Every time you measure, take two or three readings a minute and record the results using a printable tracker. If your monitor has built-in memory to store readings, take it with you to your appointments. Some monitors may also allow you to upload your readings to a secure site after you register your profile, ”recommends AHA.