Prediction of Thyrotoxicosis

The 'gold standard' method to diagnose thyroid dysfunction including thyrotoxicosis is thyroid function test (TFT), a set laboratory tests for serum thyroid hormone levels. TFT usually consists of 2 or 3 laboratory tests including 'Triiodothyronine (T3)', 'Thyroxine (T4)', and 'Thyrotropin (TSH)'. Generally, higher serum free T4 and lower serum TSH levels than respective reference ranges indicate thyrotoxicosis.

However, TFT is not recommended for people who have no symptoms of thyrotoxicosis and the symptoms of thyrotoxicosis are relatively non-specific. Therefore, patients often wait a considerably long time to visit the clinic after onset of their disease and often present with aggravated symptoms and signs. This clinical course is especially common for patients with recurrent Graves’ disease. Based on these considerations, having a simple effective monitoring tool for evaluating disease status would be helpful for monitoring patients with thyrotoxicosis.

Wearable Devices

Wearable devices including activity trackers and smart watches are typically worn on the wrist and provide the information about physical activity measures such as steps taken, energy expenditure, time spent in physical activity and sleep patterns. Moreover, they provide user's heart rate (HR) using the technology called 'photoplethysmography'. Therefore, it is now possible to collect and analyze more detailed and precise changes in HR, physical activity, and sleep patterns, which are key indicators of thyrotoxicosis but nonspecific and hard to detect with conventional on-site history taking or physical examination.

Clinical Study

A clinical study was performed for the Clinical application of continuously monitored data by wearable activity trackers in the patients with thyrotoxicosis (trial registration number, NCT03009357; https://clinicaltrials.gov). In this study, resting HR data collected by wearable devices were correlated with serum thyroid hormone levels, and persistent increase of resting HR indicated a significantly higher risk of thyrotoxicosis.

THYROSCOPE

THYROSCOPE is a web-based application which links your TFT results and HR data from your wearable device. THYROSCOPE calculates the risk level of thyrotoxicosis using these data based upon the results of the clinical study mentioned above.

The benefits of using THYROSCOPE are:

• Treatment monitoring in the patients with Graves' disease who are taking medications
• Surveillance of disease recurrence for the patients with Graves' disease who stopped taking their medication
• Surveillance of drug-induced thyrotoxicosis in the patients with hypothyroidism undergoing thyroid hormone replacement therapy

This application is not for a diagnosis of thyrotoxicosis or other thyroid disease. As mentioned above, TFT is needed to diagnose thyroid dysfunction, including thyrotoxicosis. This application should be used for reference. Please visit your healthcare provider for the clinical diagnosis of your thyroid disease.

Since this application is based on HR data to estimate a risk of thyrotoxicosis, drugs or medical conditions that also affect HR can change the risk calculation.