Apple Watch Heart Study With Stanford Signs Up 400,000 People

(Bloomberg) -- More than 400,000 people have signed up for a Stanford University study being sponsored by Apple Inc. to examine whether Apple Watch can detect patients with undiagnosed heart rhythm problems, one of the largest heart screening studies ever to be conducted.

The study, details of which were published Thursday by Stanford University researchers, will use the watch's sensors to detect possible atrial fibrillation. People who have the condition are at risk of blood clots and strokes. In the U.S., it causes 750,000 hospitalizations a year and contributes to 130,000 deaths, according to the Centers for Disease Control and Prevention.

Devices like phones and Apple's digital watch offer exciting new possibilities for researchers, since they contain sensors and other data collection tools that huge numbers of people keep with them almost all the time. A total of 419,093 people have enrolled in the Stanford study, and results are expected next year.

“One of the most exciting things in this revolution in digital health is the opportunity to reach very large numbers of people in a very short period of time without huge expense,” said Lloyd Minor, dean of Stanford University School of Medicine, in an interview. Minor called it “remarkable” that the researchers were able to recruit patients so quickly.

The goal in the study, called the Apple Heart Study, is to see if optical sensors on Apple's watch can help find undiagnosed cases of atrial fibrillation. Because it doesn't always produce outward symptoms, atrial fibrillation can go undiagnosed.

How many undiagnosed patients are out there “is one of the questions that still remains to be answered,” said Stanford University electrophysiologist Marco Perez, one of the study's lead investigators.

An unusual feature of the study is that it allows people to participate without ever visiting a doctor in person. When optical sensors on the watch detect repeated periods of irregular heart beats, patients are sent alerts on their watches to call in for a telemedicine consultation with a doctor.

If no serious conditions are found that merit urgent care, patients are then mailed a portable electrocardiogram patch that they wear for as long as seven days, and can confirm or rule out atrial fibrillation.

“It is sort of a new paradigm for how clinical trials can be performed,” said Perez.

To contact the reporter on this story: Robert Langreth in New York at rlangreth@bloomberg.net

To contact the editors responsible for this story: Drew Armstrong at darmstrong17@bloomberg.net, Jeff Sutherland

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