When measuring blood pressure, the position of the arm plays a more important role than is generally assumed. This is what researchers from the USA are currently reporting.
High blood pressure is a serious condition that is also known as the “silent killer” because it often goes unnoticed for a long time. Regular blood pressure measurements are therefore particularly important for high-risk patients.
But what happens if these measurements themselves are incorrect? A new US study shows that the way it is measured can have a significant impact on the results.
A team of researchers from Johns Hopkins University in Baltimore specifically examined the role arm position plays in measuring blood pressure. To do this, they determined the blood pressure values of 133 people between the ages of 18 and 80. The average age was 57 years.
Blood pressure measurements were taken using an upper arm cuff on the right arm. A total of three different positions were tested:
The evaluation showed clear results: When the arm rested in the lap, the upper (systolic) value was on average 3.9 mmHg higher. The lower (diastolic) value was 4.0 mmHg higher than the values measured with the arm supported. The deviations were even greater when the arm was hanging: here the systolic value was on average 6.5 mmHg higher and the diastolic value was 4.4 mmHg higher.
In short: If the arm was held in the lap or hung freely, significantly higher blood pressure values were measured than if the arm was positioned correctly on a firm surface.
Study author Dr. Tammy Brady emphasized: “The results confirm that arm position makes a big difference when it comes to an accurate blood pressure measurement.” Incorrect measurement results could therefore lead to a person incorrectly slipping into the high blood pressure range (from values of 140/90 mmHg). And: Patients may then receive medication to lower blood pressure even though they don’t need any.
If you consistently do it wrong and keep using the wrong arm position when measuring your blood pressure, it could have serious consequences for your health, says Brady. It is therefore important to adhere to the guidelines.
The recommendations suggest that you place the measuring arm loosely on a table. You should place your feet flat on the floor next to each other, because when your legs are crossed, your blood pressure increases due to the tension in your muscles.
You should also pay attention to the correct position of the blood pressure cuff: it should be approximately at the level of your heart. If the measuring point is lower, the measured value is too high; if the measuring point is higher, it is too low. The same also applies to measuring devices on the wrist.
Also important: you should not exercise, eat, drink coffee or smoke half an hour before measuring your blood pressure. All of this can distort the measurement result.