Are Wrist-Cuff Blood Pressure Monitors Accurate?
A few models can provide good-quality readings. But be sure to use them correctly.
For people with hypertension, using a home blood pressure monitor to keep track of their numbers can be helpful. But choosing an accurate device is crucial to getting good data.
The American Heart Association generally recommends opting for a home blood pressure monitor with an upper-arm cuff rather than one that has a wrist cuff. A key reason for that is accuracy, says Willie Lawrence, MD, chairman of the oversight committee of the American Heart Association’s National Hypertension Control Initiative and medical director of the Center for Better Health and Cardiovascular Wellness in Benton Harbor, Mich. “In most situations, any given arm device is going to be more accurate than any given wrist device,” he says.
In Consumer Reports’ testing, none of the wrist monitors in our ratings get top marks for accuracy.
But arm-cuff monitors don’t work for everyone. An important component of getting an accurate blood pressure reading is using a cuff that’s the right size for your arm—and some people have upper arm circumferences that are larger than can be accommodated by upper arm cuffs.
Compared with the upper arm, “the wrist diameter, because of body fat distribution, tends to have much less variability in humans,” says Atul Bali, MD, a certified hypertension specialist and clinical nephrologist at Geisinger Wyoming Valley Medical Center in Wilkes-Barre, Penn. “We can actually utilize wrist cuffs in those patients, in the absence of an appropriately sized upper arm cuff.”
Here are some other steps to take to improve the reliability of your wrist-cuff blood pressure measurements.
Get it checked. Once you have your device, take it to your doctor’s office so that your provider can check its results against the in-office results, to make sure it’s functioning properly and getting accurate readings.
Prepare right. When you take your readings, ensure that you’re following all the proper procedures for getting an accurate result. These include:
- Avoid consuming caffeine, smoking, or exercising 30 minutes before you take your blood pressure.
- Use the bathroom before you take your reading, and sit quietly for 5 minutes without talking, texting, or watching TV.
- Sit with your back straight against a sturdy chair and your feet flat on the ground. Your arm should be supported on a table in front of you. (More on positioning the device below.)
- Measure twice a day, at the same times every day (for example, in the morning and evening). Take two or three measurements at a time, a minute apart.
Use the proper positioning. One reason upper-arm cuffs are generally preferred is that they’re generally easier to position correctly. For both types of devices, the cuff should be even with your heart. That’s especially important for wrist-cuff monitors, “where you have a lot more leeway on where you position it,” says Beverly Green, MD, a senior investigator with the Kaiser Permanente Washington Health Research Institute and a family physician with Washington Permanente Medical Group.
Check the manufacturer’s instructions on how to position your wrist monitor, Green advises. One method the AMA recommends: With your elbow on the table in front of you, bend your arm and place your wrist at heart level, resting your wrist and hand against your chest. You can see a picture of this here.
Relax. When you take your measurements, it’s important to relax the muscles in your hand, wrist, and arm. Don’t make a fist or flex your wrist.