Biosignals by Wearable Devices in Hypothyroidism

Study Overview
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Brief Summary
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This is a prospective observational cohort study. Monitoring continuous biosignals using wearable devices in thyroid cancer patients who are planned to withdraw their levothyroxine for radioactive iodine therapy. Through this, bio signals can be collected in the subjects in hypothyroid status. Physical activity, heart rate, and sleep data will be collected during the study period.

Detailed Description
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A prospective observational cohort study including two groups. Hypothyroid group: Patients with differentiated thyroid carcinoma underwent total thyroidectomy Patients who are planned to withdraw their levothyroxine for radioactive iodine therapy Biosignals will be monitored continuously using Fitbit devices Control group: Patients with differentiated thyroid carcinoma underwent total thyroidectomy Patients who are planned to get rhTSH (not to withdraw their levothyroxine) for radioactive iodine therapy Biosignals will be monitored continuously using Fitbit devices Thyroid hormone levels and continuously collected bio signals including activity, heart rate, and sleep data will be obtained during study period. Association between thyroid status and bio signals will be investigated.

Official Title
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Clinical Application of Continuous Monitoring Data for Biosignals by Commercially Available Wearable Devices in the Patients With Hypothyroidism

Conditions
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Hypothyroidism

Intervention / Treatment
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* Other: levothyroxine withdrawal


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with differentiated thyroid carcinoma underwent total thyroidectomy Patients who are planned to get radioactive iodine therapy Patients who are able to use wearable device and smartphones Exclusion Criteria: Patients who are not able to use wearable device and smartphones Patients who are maintaining drugs affecting heart rate Patients who have any other disease which can affect biosignals

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Hypothyroid group<br>Patients with differentiated thyroid carcinoma underwent total thyroidectomy Patients who are planned to withdraw their levothyroxine for radioactive iodine therapy Biosignals will be monitored continuously using Fitbit devices | Other: levothyroxine withdrawal<br>* All participants of this study are decided to get radioactive iodine therapy using levothyroxine withdrawal or human recombinant TSH injection prior to the study enrollment. That decision is independent with this study protocol. This study just collect continuous bio signals using wearable devices in the patients undergoing two different preparation methods for radioactive iodine therapy. That is why this study is an observational cohort study.<br>|
| Control group<br>Patients with differentiated thyroid carcinoma underwent total thyroidectomy Patients who are planned to get rhTSH (not to withdraw their levothyroxine) for radioactive iodine therapy Biosignals will be monitored continuously using Fitbit devices | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| physical activity (steps) | steps data measured by wearable device, collected and recorded in 1 min increment | throughout the study period average 4 months | 
| heart rate (beats) | heart rate data measured by wearable device, collected and recorded in 1 min increment | throughout the study period average 4 months | 
| free T4 level (ng/dL) | thyroid hormone level | baseline (visit 1) | 
| free T4 level (ng/dL) | thyroid hormone level | after 2 to 3 months (visit 2) | 
| free T4 level (ng/dL) | thyroid hormone level | after 3 to 4 months (visit 3) | 
| Zulewski hypothyroidism score ( point) | Scoring system to evaluate hypothyroid symptoms and signs | baseline (visit 1) | 
| Zulewski hypothyroidism score ( point) | Scoring system to evaluate hypothyroid symptoms and signs | after 2 to 3 months (visit 2), | 
| Zulewski hypothyroidism score ( point) | Scoring system to evaluate hypothyroid symptoms and signs | after 3 to 4 months (visit 3) | 
| TSH level (mIU/L) | thyroid stimulating hormone level | baseline (visit 1) | 
| TSH level (mIU/L) | thyroid stimulating hormone level | after 2 to 3 months (visit 2) | 
| TSH level (mIU/L) | thyroid stimulating hormone level | after 3 to 4 months (visit 3) |