«Numerous studies have demonstrated the accuracy of heart rate data from wearable devices when compared with conventional measurement, even though there is minor variability between smartwatch brands.»

«Regarding heart rhythm, a large trial published in The New England Journal of Medicine, the Apple Heart Study, recruited 419,297 patients and found a positive predictive value of 84% between notifications of irregular heart rhythm on the Apple Watch and diagnosis of atrial fibrillation.»

«One study revealed that wearable device heart rates could correlate well with patients’ thyroid disease state. This study looked at 30 patients with hypothyroid and 14 patients with euthyroid in the setting of receiving radioactive iodine therapy for thyroid cancer. They found that a decrease of Fitbit heart rate by 1 standard deviation was associated with a 0.2 ng/dL decrease in free thyroxine levels and a twofold increase in the odds ratio of hypothyroidism. Heart rate measured by wearable devices showed better sensitivity than resting heart rate measured in the office setting owing to higher volume and frequency of data collected.»

«So we believe that in the near future, physicians will commonly prescribe a wearable wrist device alongside measurement of thyroid function tests to support management of patients’ thyroid disease.»

Article written by Anand Narayanan, Aaron Neinstein.