Apple and Stanford University School of Medicine each released a press release today citing the findings of the Apple Heart Study, which they announced together in November 2017. Stanford Medicine also delivered its findings to the 68th Annual Scientific Session and Expo of the American College of Cardiology today. Apple has fully funded the study.
The Apple Heart Study, which did not include the Apple Watch Series 4 (with the built-in ECG function), had 419,093 participants. Apple says people from all 50 states have participated over the course of eight months. According to the University, around 0.5 percent of all participants ̵
In cases where users were notified of an irregular heart rhythm, physicians provided study participants with a digital consultation and an electrocardiogram patch for further monitoring; The readings of their electrical heart rhythm were recorded in these cases with the correct ECG patch for up to a week.
Stanford has learned more about how all this has developed:
comparisons between irregular pulses. Apple Watch detection and simultaneous ECG recording (ECG) showed that the pulse detection algorithm (which displays a positive tachogram value) has a predictive value of 71 percent. In 84 percent of the respondents, participants who received irregular impulses were at the time of reporting atrial fibrillation.
One-third (34 percent) of participants who received irregular pulse warnings followed with one. An ECG patch more than a week later detected atrial fibrillation. Since atrial fibrillation is an intermittent condition, it is not surprising that it remains undetected during the subsequent monitoring of the ECG patch.
57% of those receiving irregular pulse warnings sought medical attention.
Stanford treats the Apple Heart Study as a step in further research on how useful portable consumer devices can be in monitoring our daily health and predicting problems. "Atrial fibrillation is just the beginning, as this study opens the door to further research to explore wearable technologies and how they could be used to prevent diseases before they strike – a key goal of Precision Health," Dr. Lloyd Minor, Dean of Stanford School of Medicine.
We know that these devices (from Apple and many other companies) can save and improve lives, but recognizing undiagnosed health problems is multi-layered, which involves monitoring core fitness activity and asking whether the heart beats it should, these are duties of most wearables of today. There is little room for inaccuracies when tech manufacturers want to take the next step. Again, this study included only the Apple Watch up to Series 3, relying heavily on the device's optical heart rate sensor. When you connect to a medical facility for a heart check, more specialized devices are available.
"The performance and accuracy we observed in this study provide important information to understand the potential impact of wearable technology on the health care system," said Drs. Marco Perez, professor of cardiovascular medicine. "Further research will help people to make more informed health decisions."
Even with the newer Apple Watch Series 4, Apple has tried to say that the ECG function is not a medical diagnostic tool. If there are several consecutive abnormal readings, this will be displayed. These devices are not intended to diagnose your own health or to respond to the information they provide without consulting a real doctor. Smartwatches and fitness trackers can detect irregularities or sudden crashes, but are not yet in a place where everyone can fully rely on them.