We live in a world obsessed with data. Devices grow continually smarter, capturing vast amounts of information about every conceivable topic: online behaviors, consumer preferences, even individual sleep patterns. As access to this tantalizing human data has grown, so have the strategies and software tools for analyzing it. Field expert Bruce Barnes claims that big data analysis offers a “new level of knowing” especially suited for “sharing and leveraging information.”
Despite this trend, medical professionals struggle to leverage a significant body of health-related data. Why? Fitness trackers, smartwatches, and health apps collect and store real-time health data, but their scientific validity remains mostly untested. Because of this, medical professionals are often hesitant to incorporate that information into diagnoses or treatment.
Recently, however, a group of researchers at University of California, San Francisco sought to remedy this. They began their experiment in a cardiology clinic, taking simultaneous heart rate readings on an electrocardiogram (ECG) and a smartphone photoplethysmography (PPG) app. Based on their 50-patient sample, their results show a 0.90 overall agreement between the two readings. The only inconsistent readings occurred in patients with irregular heart rhythms.
That finding alone is significant, since it validates the accuracy of smartphone PPG. The Health eHeart study delved further into the topic by gathering 66,788 remote participants who sent in more than 3 million smartphone-derived heart-rate readings. Having demonstrated the legitimacy of smartphone PPG, they hoped to establish real-world heart-rate norms that would give doctors a point of reference when interpreting data gathered by fitness trackers, phones, or apps.
The results revealed an average real-world heart rate of 79.1 bpm. The researchers also found that having a higher body mass index (BMI) or being female correlated with a higher heart rate, and they confirmed that increased age also correlated with a reduced heart rate.
Experiments like this Health eHeart study forge usable connections between medical professionals and the new realm of data collected by fitness trackers, smartwatches, and health apps. More research is still needed, especially into populations with heart-rate irregularities, but increased insight and acceptance of these smart devices and the medical data they collect stand to benefit doctors and patients alike.