Apple Heart Study Finds Value in Using mHealth Wearables to Detect AFib

The largest-ever study of a consumer-facing mHealth wearable finds that the Apple Watch can be used by clinicians to detect atrial fibrillation.

But the question remains: Will care providers trust devices like smartwatches and fitness bands to deliver the data they need to treat their patients?

According to researchers at the Stanford University School of Medicine, almost 420,000 people participated in the Apple Heart Study, launched in 2017 in a partnership with Apple and American Well, the largest analysis to date of consumer-facing technology for clinical purposes. Over an eight-month span, the Apple Watch detected an irregular heart rate in .52 percent, or 2,161 people.

Those participants with an irregular pulse were scheduled for a consult with a specialist on American Well’s telehealth platform, then given an ECG patch about two weeks later and were monitored for one week. Of that group, 34 percent were diagnosed with AFib.

“Because atrial fibrillation is an intermittent condition, it’s not surprising for it to go undetected in subsequent ECG patch monitoring,” Stanford Medicine said in a press release accompanying the study, which was published in The New England Journal of Medicine. “Comparison between irregular pulse-detection on Apple Watch and simultaneous electrocardiography (ECG) patch recordings showed the pulse detection algorithm has an 84 percent positive predictive value.”

In addition, the study found that roughly three-quarters of the users who received a notification of having an irregular pulse contacted a care provider for further treatment.

“The study’s findings will help patients and clinicians understand how devices like Apple Watch can play a role in identifying atrial fibrillation, a deadly and often undiagnosed disease,” Mintu Turakhia, MD, an associate professor of cardiovascular medicine, said in the press release. “Additionally, these important findings lay the foundation for further research into the use of emerging wearable technologies in clinical practice and demonstrate the unique potential of large-scale app-based studies.”

The study seeks to close the gap between popular consumer-facing devices and a skeptical healthcare industry by proving that these tools, if designed and properly vetted, can help clinicians monitor and treat patients in remote patient monitoring programs. But challenges remain.

In a CNBC story written by Christina Farr, some clinicians pointed out that treatment for AFib varies according to the patient, so a doctor can’t just take the results coming from an mHealth platform and develop a treatment plan. In addition, many people with AFib aren’t seeking treatment, and doctors aren’t treating enough of those with the chronic condition.

Finally, some clinicians have expressed worries that mHealth devices could overstimulate the fears of the general public, flooding EDs, clinics and doctors’ offices with people who see irregularities reported by their devices and think they need immediate care.

Marco Perez, MD, an associate professor of cardiovascular medicine at Stanford Medicine and lead author of the study, said this study is just the beginning, and a step in the right direction. He’ll be presenting on the results of the study at the American Heart Association’s 2019 Scientific Sessions later this week.

“The performance and accuracy we observed in this study provides important information as we seek to understand the potential impact of wearable technology on the health system,” he said in the press release. “What the Apple Heart Study shows us is that atrial fibrillation is just the beginning. We can look ahead to other areas of preventive medicine. Further research will help people make more informed health decisions.”