Scientists have issued a warning to Apple Watch users that it’s crucial to understand that the hypertension notifications feature is not a replacement’ for proper health checks.
New research warns the feature, which aims to spot signs of high blood pressure, should not be used instead of regular screening tests. Users should not rely on their watch to alert them to changes in their blood pressure due to the risk of ‘false reassurance’, researchers warned.
Apple has a ‘hypertension notifications feature’ which it says is ‘not intended to diagnose, treat or aid in the management of hypertension or other conditions such as blood clots, stroke, atrial fibrillation, congestive heart failure or high cholesterol’.
The feature is designed to look for patterns of chronic high blood pressure via a heart sensor and uses a 30-day evaluation, but it states that not all people with high blood pressure will receive a notification.
In the new study, researchers from the US noted that its Food and Drug Administration approved the Apple Watch hypertension feature for use last year.
However, looking at Apple data to assess the real-world impact of the technology, the researchers found ‘moderate evidence to rule in hypertension’ and ‘weak evidence to rule out hypertension’.
“According to Apple’s reported test performance, 41.2% of individuals with undiagnosed hypertension would receive an alert for potentially having hypertension, and 58.8% would not,” .
“Among those without hypertension, 92.3% would not receive an alert and 7.7% would receive an inappropriate alert.”
High blood pressure, also called hypertension, can lead to serious problems like heart attacks or strokes. The condition is very common, especially in older adults and usually causes no symptoms.
Professor Bryan Williams, chief scientific and medical officer at the British Heart Foundation (BHF), said this means high blood pressure ‘is known as the silent killer’.
“Untreated, high blood pressure contributes to tens of thousands of preventable heart attacks and strokes in the UK each year,”
“We need more opportunities for people to get their blood pressure checked quickly and easily to avoid more preventable heart attacks and strokes. Smart tech like this can be useful for people who want to keep a closer eye on various aspects of their health.
“The potential to alert about possible hypertension will also prompt wearers of this technology to get their blood pressure formally checked. But this analysis makes it clear that we should not rely on this type of wrist-worn technology alone to warn us if we have high blood pressure, as most people with undiagnosed high blood pressure in this analysis would not have received an alert.
“It’s crucial that people understand that this technology is not a replacement for getting your blood pressure checked with standard cuff-based devices.”
The research team concluded in the study:
“With more than 200 million Apple Watch users worldwide, the hypertension notification feature offers new opportunities to identify adults with undiagnosed hypertension, but with potential for hypertension misclassification as well.
“A large proportion of individuals unaware of their hypertension may be made aware. However, an even larger proportion of individuals with undiagnosed hypertension could receive no alert at all. Apple indicates that the feature is not intended to diagnose hypertension and is designed to prompt users to seek clinical evaluation if hypertension is suspected.
“However, false reassurance may discourage some individuals with undiagnosed hypertension from obtaining appropriate screening or engaging with the healthcare system, resulting in missed opportunities for early detection and treatment.”
