- A new report states that only 6 percent of home blood pressure monitoring devices are checked for accuracy.
- However, experts say it’s more important that people know how to use these devices correctly.
- They say people should routinely check their device’s readings with the reading done during a checkup at the doctor’s office.
- Inaccurate blood pressure readings can result in people not getting the treatments for hypertension that they may need.
Testing your blood pressure at home is recommended by the American Heart Association for those at risk of high blood pressure as well as those living with hypertension.
However, a new study published in the journal Hypertension reports as few as 6 percent of devices sold to self-monitor blood pressure are tested for accuracy.
While the findings are based on data from Australia’s online marketplace, the same suppliers serve markets worldwide.
Experts in the United States say they worry less about the actual devices, which are approved by the Food and Drug Administration (FDA), and more about how people use them.
“In my experience, measurements performed at the doctor’s office are the most reliable, and no home monitoring device can match this level of accuracy,” said Dr. Javier Morales, a primary care physician and associate clinical professor at the Donald and Barbara Zucker School of Medicine at Hofstra/Northwell in New York as well as vice president of principal trials investigator at the Advanced Internal Medicine Group in New York.
Morales has been a practicing internist specializing in diabetes, obesity, and metabolic diseases for more than 20 years.
“With virtual health and at-home monitoring becoming more common now, my biggest concern is the patient’s ability to use the devices correctly,” he told Healthline.
Dr. Michael Rakotz, a family physician, a clinical assistant professor at the Feinberg School of Medicine at Northwestern University in Illinois, and the vice president of Health Outcomes at the American Medical Association, says accurate blood pressure measurements are crucial.
“If blood pressure isn’t measured correctly, whether it’s in a physician’s office or at home, the potential risks can be serious,” Rakotz told Healthline.
Experts add that inaccurate results may lead to prolonged and untreated high blood pressure.
“Left untreated, uncontrolled blood pressure leads to an increased risk of stroke, heart attack, heart failure, and can cause damage to your kidneys, memory, and vision,” Morales said.
“The chances of misclassifying blood pressure goes up,” added Rakotz. “That could mean someone who doesn’t have high blood pressure gets diagnosed as having it, or someone with uncontrolled high blood pressure doesn’t get the treatment they need.”
“This is why healthcare professionals and people self-measuring their blood pressure need to be trained to perform the measurements correctly,” said Rakotz.
Factors contributing to higher than normal blood pressure levels include advancing age, high salt intake, low fruit and vegetable intake, being overweight, not getting adequate exercise, and drinking alcohol excessively, says Rakotz.
Along with home screenings and attending in-office checkups, experts say people can maintain a healthy blood pressure or help lower their blood pressure by making a few lifestyle changes.
“My patients are encouraged to practice [eating] a good diet, regular exercise, and taking their medications as prescribed,” said Morales.
The American Heart Association also advises that people with high blood pressure or hypertension reduce their risks and enhance the effectiveness of blood pressure medications by reducing stress, quitting smoking, limiting alcohol, and working together with their doctor.
If you’re unsure about your home blood pressure test’s accuracy, contact your primary care physician.
If possible, experts suggest that people compare their home device readings with in-office readings.
“This would help to ensure that the home monitoring device is getting similar results as the equipment in the office,” said Morales.
If you can’t visit your doctor’s office, make sure you know which type of testing device you should use and how to use it properly.
“For better accuracy, I would recommend the arm cuff-style over the wrist monitors,” said Morales.
“Central blood pressure monitoring, which measures the blood pressure in the aorta (the large artery that sends blood from the heart throughout the body), is considered most accurate,” he added.
“The larger the blood vessel, the less likely that blood pressure measurement would be prone to error,” he said. “The arm cuff-style devices measure [blood pressure] on larger blood vessels than the wrist style devices, therefore, they will provide better accuracy.”
Some people with diabetes and vascular diseases, he added, may have blood vessels that are already hardened, and their blood vessels will be less compressible by the blood pressure cuffs.
“These patients should be aware their readings will not be as accurate as those not suffering from vascular disease,” said Morales.
Knowing where to place the sensors is also essential.
“If the sensors are not placed correctly, then the blood pressure reading will be faulty, and additional therapeutic measures implemented could be catastrophic with such an inaccurate reading,” Morales said.
The arm you choose can affect your overall reading, too.
“The right arm is in principle more accurate because of a potential abnormality called cervical rib syndrome that can impact [blood pressure] readings when measured in the left arm,” Morales added.
“Cervical rib syndrome is an entity where the artery supplying the left arm could be compressed between the first rib and one of the strap muscles of the neck. When the left artery is compressed by the cervical rib, it can lower your blood pressure reading,” he said.
Finally, Morales says to make sure you have fresh batteries and, if using an outside power source, ensure it’s working properly.