Hypertension: Apple Watch only recognizes 4 out of 10 cases

In around 30 days, Apple watches will warn the first straps of possible high blood pressure: With Watchos 26 and iOS 26, Apple has sent its latest health function into the race with the “High blood pressure messages”. It started on time for the publication of the operating system updates at the beginning of this week and was previously nodded off by regulatory authorities in several countries. The function is also available in Germany.

The warnings can be activated not only on Ultra 3 and Series 11, but from Series 9 and Ultra 2. The Apple Watch SE does not support this.

Watch does not provide blood pressure values

When activating the warning notices, Apple points out that “not every case is identified by high blood pressure”. Apple own study According to the clinical validation of the function, however, the warning only stated in almost 30 percent of the study participants with high blood pressure (hypertension degree 1). Under participants with high blood pressure severity 2, the watch recognized the clinical picture in a good half of the cases.

In average, the watch only noticed the clinical picture in around 4 out of 10 people with high blood pressure. Hypertension risk opera should not rely solely on the new warning function of the Watch, but should continue to log their blood pressure by her doctor or with a medical blood pressure monitor.

The watch cannot measure the blood pressure. The high blood pressure messages rely on the existing optical heart sensor and photoplethysmography. The technology captures changes in blood volume in the vessels by shining the led light on the back light into the wrist and measures reflection. A new algorithm pays attention to signs of high blood pressure, the measurements are carried out during the day-and not when it comes to sleep tracking. If corresponding patterns are recognized over a period of 30 days, the watch sends a warning notification and advises you to visit the doctor and to control the values ​​with a blood pressure monitor. This can now be specifically logged in Apple Health, with memory – another innovation of iOS 26.

False alarms rarely – and possibly useful

After all, false alarms – i.e. a wrong warning to users without high blood pressure – occurred comparatively rarely, according to Apple’s validation study. Of the few users who received a false alarm, a “significant proportion” also had a slightly increased blood pressure, Apple writes – accordingly, the incorrect warning can even make sense to counteract early. In the first year, over a million watch carriers could receive such warnings, Apple put a record last week.