Apple Watch and iPhone could enable at-home assessment of functional capacity in cardiovascular disease patients.
According to data published this week by Stanford University researchers in PloS ONE, Under a supervised in-clinic setting, the smartphone and Apple Watch with the VascTrac app were able to accurately assess ‘frailty’ with a sensitivity of 90% and specificity of 85%.
Outside the clinic in an unsupervised setting, the home-based 6MWT is 83% sensitive and 60% specific in assessing “frailty.”
Passive data collected at home were nearly as accurate at predicting frailty on a clinic-based 6MWT as was a home-based 6MWT, with area under curve (AUC) of 0.643 and 0.704, respectively.
Conducted by Stanford University researchers and funded by Apple, the study provided 110 Veterans Affairs patients with the devices and compared their standard 6MWT performance to an in-clinic version measured by the Apple sensors, regular at-home 6MWT tests conducted through a study app, and passively collected activity data.
The main conclusion according to this study is that passive activity data acquired by an iPhone and Apple Watch are an accurate predictor of in-clinic 6MWT performance.
- Use the six-minute walking test score (6MWT) on Apple Watch to monitor your fitness
- Monitor your injury recovery and mobility using your iPhone and Apple Watch
This finding suggests that frailty and functional capacity could be monitored and evaluated remotely in patients with cardiovascular disease, enabling safer and higher resolution monitoring of patients.
The study was conducted between May 2018 to May 2019.
Researchers invited 156 ambulatory patients with cardiovascular disease and scheduled procedures through the Palo Alto VA Hospital to participate, 110 of whom eventually participated.
Participants were provided with an iPhone 7 and Apple Watch Series 3 that were loaded with the VascTrac app developed by the team.
Apple introduced a series of new mobility-related features on watchOS 7. One of the main features was the 6MWT( Six-minute-walking-test), which is a golden standard to evaluate the functional mobility of a patient.
The mobility metrics can be found in the Health app on your iPhone.
The six minute walk test is also considered a measure of your capacity for exercise. Longer distances are associated with healthier cardiac, respiratory, circulatory and neuromuscular function according to Apple.