Major study suggests Apple Watch can detect irregular heartbeat

More work needed to see if wearables can help screen for heart problems, but researchers call study encouraging

More than 419,000 users signed up for the study, the largest ever to explore screening healthy people for atrial fibrillation. Photograph: Issei Kato/Reuters

A huge study suggests the Apple Watch can detect a worrisome irregular heartbeat – but experts say more work is needed to tell if using wearable technology to screen for heart problems really helps.

More than 419,000 Apple Watch users signed up for the study, which was funded by Apple and the largest ever to explore screening seemingly healthy people for atrial fibrillation (A-fib), a condition that if untreated eventually can trigger strokes.

Stanford University researchers reported on Saturday that the watch warned just 0.5% of participants – about 2,100 – that they might have a problem.

Blow to low carb diet as landmark study finds high fibre cuts heart disease risk
Read more
Even among those flagged, the watch’s diagnosis was “not perfect”, said Dr Richard Kovacs of the American College of Cardiology, who was not involved with the study.

People who received an alert were supposed to consult a study doctor via telemedicine and then wear an EKG patch measuring cardiac activity for the next week. Some skipped the virtual check-up to consult their own doctors. Overall, about 57% sought medical attention.

Among those who got EKG monitoring through the study, a third had atrial fibrillation, according to preliminary results being presented at an American College of Cardiology conference in New Orleans.

A-fib tends to come and go, and a week of monitoring might have missed some cases, said the Stanford lead researcher Dr Mintu Turakhia. But if the watch detected another irregular heartbeat while someone was wearing the EKG patch, 84% of the time it really was a-fib, he said.

“This study we believe provides very encouraging evidence that a device, the Apple Watch, can be used to detect a-fib and to point out to people when additional monitoring or testing may be needed,” said Dr Lloyd Minor, Stanford’s dean of medicine.

Other cardiac experts said the study suggests screening with wearable technology might be technically feasible eventually, but needs lots more research.

“I would not advise this to the overall general population,” said Dr Valentin Fuster, director of Mount Sinai Heart in New York and a former American Heart Association president, who was not involved with the study.

Instead, he said, he would like to see it tested in seniors with risk factors such as high blood pressure.

The powerful in tech…
… must keep being challenged with bold investigative journalism. It’s been a year since The Observer and The Guardian broke the story that became the Cambridge Analytica scandal, exposing the truth and shedding light on the reality of foul play within the tech industry. We saw how personal data could be harvested on an unprecedented scale to fulfill the ambitions of the powerful. Through this courageous investigative reporting, we shamed Facebook, and prompted a global conversation about the importance of data privacy, holding tech companies to account and pressuring governments to enact regulation.

The Guardian is committed to continuing this vital work; we will keep persevering, uncovering and challenging those with so much power in the tech industry. This has never been so pressing: we’re living in a time when the integrity of our democracy and the legitimacy of our votes are in question. Political campaigns reside in our many digital feeds and, with each year, this will become ever more prominent. The world needs journalism that promotes transparency and investigates where others won’t go. Reader support means The Guardian can keep investigating the critical issues of our time.

The Guardian is editorially independent, meaning we set our own agenda. Our journalism is free from commercial bias and not influenced by billionaire owners, politicians or shareholders. No one edits our editor. No one steers our opinion. This is important as it enables us to give a voice to those less heard, challenge the powerful and hold them to account. It’s what makes us different to so many others in the media, at a time when factual, honest reporting is critical.