Most Apple Watch users won’t get health benefits from AFib detection, study finds

Photo by Vjeran Pavic / The Verge

A type of irregular heart rhythm called atrial fibrillation is one of the conditions that the Apple Watch is supposed to detect. A new study shows that most people who wear the watch are in a demographic that wouldn't be able to do much with that information.

Josh Pevnick, co-director in the division of informatics at Cedars-Sinai Medical Center in Los Angeles, says that getting an alert about a heart rhythm doesn't help the typical Apple Watch user's overall health.

Most research on the health features on Wearable devices has focused on whether they can accurately identify a potential problem like Atrial Fibrillated, which Apple, Fitbit, Withings, and SAMSUNG watches are Food and Drug Administration-cleared to detect. Being able to do something about an issue is different from detecting an issue. Pevnick and other researchers are wondering about how useful the information about atrial fibrillation is to patients after reading this new study.

Blood thinners are often prescribed to people with a higher risk of strokes. Blood thinners are not usually used for younger people without other factors that could increase stroke risk, according to Pevnick. Most Apple Watch users at the Center fell into that category.

He says that most of the people who are connecting their devices wouldn't have anticoagulants recommended anyway.

Patients at Cedars-Sinai Medical Center can connect their Apple Watch data to their electronic medical record. The research team looked at the Apple Watch and clinical data from around 1,800 patients for the study.

The study did not look at how many people got an irregular heartbeat. Only 0.25 percent of people wearing an Apple Watch at the Center would be eligible for anticoagulants if they had atrial fibrillation flagged by the device.

According to Pevnick, the findings show that the typical Apple Watch user isn't the group that doctors are most concerned about.

The study shows how Apple Watch opened new questions for doctors to try and address. Older people who qualify for medication to address the risks it poses are the majority of the time. A new category of younger, healthier people have been created because of the introduction of smartwatch tools that can detect abnormal heart rhythms. Pevnick says doctors don't know the best way to handle that group.

He says that they are picking up a different type of arrhythmia.