Apple, Samsung, and now Microsoft are working on developing wearables that measure blood pressure from unconventional locations.
Whether they are smart or traditional, BPMs typically come in one two forms—those for the upper arm, and those for the wrist. Both employ inflatable cuff technology, although blood pressure measurements taken at the wrist may be less accurate. That is because the wrist arteries are narrower and not as deep under your skin as those on the forearm.
But a number of companies are experimenting with moving away from these locations.
At CES 2018 earlier this year, Omron showcased HeartGuide, a watch-sized sphygmanometer that promises readings as accurate as you would get from upper arm models. The device should land in the fall of 2018.
Tech giants are also moving into this area. Apple has recently patented a self-inflating blood pressure monitoring watch. It comes with a cuff equipped with sensors integrated into a collection of tiny airbags. Then there is Samsung’s upcoming Galaxy Watch. It is rumored to be able to keep tabs on your readings by shining polarized light and then sensing the intensity of the scattered light.
But Microsoft might have taken the strangest route of all in coming up with a blood pressure monitoring device. The prototype was revealed in a report by Christian Holz and Edward Wang of Microsoft Research.
Dubbed Glabella, the glasses come with optical sensors concealed inside the frame. From there, they continually measure pulse waves at three different locations on the user’s face, and then calculate the time and rate between these areas and the heart to calculate blood pressure. The glasses also collect data on physical activity so can function as a 24/7 activity tracker.
Interestingly, the sensors have only been shown to be accurate for taking systolic pressure. This is the top number or highest blood pressure when the heart is pushing the blood round the body. While it is generally considered to be more important than diastolic pressure, both readings have their use. Systolic pressure is better for determining your risk of having a stroke or heart attack. A high diastolic pressure, on the other hand, is bad for the heart because it shows the heart is not relaxing enough which can lead to other cardiovascular problems.
The report says it conducted a real-world trial which showed the technology to be accurate. Whether we’ll actually see a commercial version of this product is not entirely clear. Manufacturers often patent technology that never progresses past the planning stage. Patents make it more difficult for others to move in and poach ideas.