Google's smartwatch AI can flag high blood pressure without a cuff

Google Research has built an AI that looks for signs of high blood pressure using only the pulse sensor and motion sensor in a regular smartwatch. It needs no blood pressure cuff for setup. The work was published in Nature, and Google says it is already part of the blood pressure trends feature in the Google Health app.

How it works

The AI learned from nearly 500,000 hours of sensor data. It compared short segments and worked out which ones came from the same person, without being told anyone's diagnosis. It then averages these patterns over several days and gives a probability of high blood pressure.

What the study found

The study covered 196 people at five US research sites. The watch method caught 65.8 percent of the people with high blood pressure. A standard in-office measurement caught 55.3 percent. That is still far from perfect, and the material does not say how often the watch raised a false alarm.

What is not clear yet

Google says the method is still a research project and does not replace a diagnosis. The aim is to nudge people to get checked. Google also says more than half of people with high blood pressure do not know they have it. The material does not say which watches are supported, what the feature costs, or when everyone will see it.