A new study shows that the Apple Watch can detect atrial fibrillation with reliable accuracy. The randomized study included patients over 65 years of age at risk of stroke, and compared conventional medical treatment in the Netherlands with wearing an Apple Watch.
It should be noted that the sample size is limited, including 437 participants with an average age of 75 years, which may affect the results in different populations, but the basic conclusions appear consistent.
The study focused on detecting atrial fibrillation over a six-month period. The Apple Watch used cardiac functions such as ECG and PPG sensor to monitor the condition, and was compared to a routine visit to a doctor or family doctor in the control group.
The results showed that after six months, atrial fibrillation was detected in 9.6% of Apple Watch users, compared to only 2.3% in the control group, representing a statistically significant difference.
This superiority is because atrial fibrillation does not always occur continuously and may not be noticed by the patient. Therefore, even if a smartwatch is less able to detect a single episode than a doctor, wearing it for long hours per day increases the likelihood of detecting the condition over an extended period of time. The watch was also able to detect asymptomatic atrial fibrillation.
However, the results showed that the Apple Watch is not 100% accurate, with about half of the warnings turning out to be false positives. Like the hourly blood pressure feature, this warning is not associated with direct negative consequences, other than the possibility of feeling anxious or wasting additional time when visiting the doctor.
