Apple Watch could miss hypertension diagnoses in seniors

While smartwatch-based notification features can help identify adults with undiagnosed hypertension, there is a potential for hypertension misclassification as well, new research reveals.

Published in JAMA, the study assessed the impact of the Apple Watch hypertension notification feature on screening among U.S. adults without diagnosed hypertension. Apple launched the feature as part of the Apple Watch Series 11 last year, stating that the smartwatch's algorithm will passively review blood vessel data over 30-day periods, notifying users if it identifies patterns indicating hypertension. The Food and Drug Administration cleared the feature in September 2025.

Researchers from the University of Utah and the University of Pennsylvania, who conducted the study, noted prior research showing that 58.8% of people with undiagnosed hypertension did not receive an Apple Watch alert. About8% of those without hypertension received a false alert. Thus, they set out to examine how Apple Watch hypertension notifications would change the probability that a person has hypertension.

The researchers analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2017-2020. They included data from 3,983 NHANES participants, 22 years or older, who were not pregnant and were not aware of a prior hypertension diagnosis.

They found that receiving an alert increased the probability of having hypertension from 14% to 47% among people younger than 30. Not receiving an alert lowered the odds of hypertension to 10% for this population.

But for adults 60 and older, receiving an alert increased the probability of having hypertension from 45% to 81%, and not receiving an alert reduced it to 34%. This means that older adults with hypertension may go undiagnosed by the smartwatch feature.

Additionally, the study shows variation in alerts and hypertension probability across racial and ethnic groups. Receiving an alert increased the probability of having hypertension from 36% to 75% among Black adults, while not receiving an alert lowered it to 26%. Meanwhile, an alert increased the probability of hypertension from 24% to 63% for Hispanic adults, while the absence of an alert lowered the probability to 17%.

Researchers concluded that though a "large proportion of individuals unaware of their hypertension may be made aware" through the Apple Watch notification, "an even larger proportion of individuals with undiagnosed hypertension could receive no alert at all." 

In a press release, Adam Bress, Pharm.D., senior author and researcher at the Spencer Fox Eccles School of Medicine at the University of Utah, underscored that the Apple Watch hypertension notification feature should supplement, and not replace, standard blood pressure screening.

Anuja Vaidya has covered the healthcare industry since 2012. She currently covers the virtual healthcare landscape, including telehealth, remote patient monitoring and digital therapeutics.