Patient-centered Dosage of Levothyroxine

Patient-centered Decision Support Tool for Levothyroxine Dosage

Levothyroxine is the most used thyroid hormone replacement when the thyroid gland is failing. Because dosage adjustment normally takes several months, the investigators have developed a decision support tool (DST) that predicts optimal dosage based on repeated blood samples the first 2 weeks after initiation of therapy. In this randomized study the investigators will include patients that start levothyroxine therapy after total thyroidectomy. The use of DST to advice the physician about an early dosage adjustment will be compared with common clinical practice, that is dosage adjustment every 2 months. The effect of DST use will be assessed by studying the possible relationship between fast optimal dose adjustment, patient reported outcome measures, and ability to work.

Study Overview

• Status: Recruiting
• Conditions: Hypothyroidism; Thyroid; Thyroid Cancer
• Intervention / Treatment: Other: Decision support tool

• Study Type: Interventional
• Enrollment (Estimated): 240
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Vegard Brun, PhD; Phone Number: 0047 77669260; Email: vegard.heimly.brun@unn.no
• Study Contact Backup: Name: Solveig Brun, cand.med; Phone Number: 004745253006; Email: solveig.konst@unn.no

Study Locations

• Norway
  • Bergen, Norway
    • Recruiting
    • Haukeland University Hospital
    • Contact: Renate Kollevåg Vik, PhD; Phone Number: +4795210732; Email: Renate.Cecilie.Kollevag.Vik@helse-bergen.no
  • Oslo, Norway
    • Recruiting
    • Oslo University Hospital
    • Contact: Ingrid Alm Andersen, PhD; Phone Number: +47 91 50 27 70; Email: aningr@ous-hf.no
  • Tromsø, Norway, 9010
    • Recruiting
    • University Hospital of North Norway
    • Contact: Solveig Konst, Cand.Med; Phone Number: +4777754259; Email: solveig.konst@unn.no

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Total or completion thyroidectomy for differentiated thyroid cancer og benign thyroid nodules at Norwegian hospitals

Exclusion Criteria:

• Anaplastic thyroid cancer, thyroid cancer with distant metastasis, graves disease, toxic nodules, pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control; Current clinical practise. Levothyroxine dose is calculated based on weight and adjusted according to TSH-level at 6-8 week intervals until biochemical target is reached
Experimental: DST 1; Levothyroxine dose is calculated using the current version of the decision support tool based on 4 blood samples.	Other: Decision support tool; Patients in the intervention groups are given the option to use the decision support tool when adjusting the levothyroxine dose after total thyroidectomy. Levothyroxine therapy is not a part of the intervention, as all patients receive this therapy regardless of study participation.
Experimental: DST 2; Levothyroxine dose is calculated using an improved mathematical model in the decision support tool based on 4 blood samples.	Other: Decision support tool; Patients in the intervention groups are given the option to use the decision support tool when adjusting the levothyroxine dose after total thyroidectomy. Levothyroxine therapy is not a part of the intervention, as all patients receive this therapy regardless of study participation.
Experimental: DST 3; Levothyroxine dose is calculated using an improved mathematical model in the decision support tool based on 2 blood samples.	Other: Decision support tool; Patients in the intervention groups are given the option to use the decision support tool when adjusting the levothyroxine dose after total thyroidectomy. Levothyroxine therapy is not a part of the intervention, as all patients receive this therapy regardless of study participation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of patients at biochemical target	Number of patients at biochemical target. Biochemical target is TSH (thyroid stimulating hormone) 0,5-2,0 mIE/L for patients on substitution therapy and 0,1-0,5 mIE/L for patients on suppression therapy	Outcome is measured at 8 weeks, 6 months and 12 months post surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time to biochemical target	Time to biochemical target is reached measured in days. Day 0 is day of surgery	Measured at 18 months after surgery
Distance from biochemical target	Distance measured in TSH units.	Measured at 8 weeks post surgery
Patient reported outcome - ThyPRO39 questionnaire	Patient reported outcomes measured by the validated questionnaire ThyPRO39. The ThyPRO39 questionnaire consist of 12 scales that covers physical symptoms (goiter, eye symptoms, hypo- and hyperthyroid symptoms), cosmetic appearance, physical, mental and social well-being and function. Each item is rated on a 0-4 scale from 0 = no symptoms/problems to 4 = Severe symptoms/problems. The average score of items in a scale is divided by four and multiplied by 100 to yield thirteen 0-100 scales, with higher scores indicating worse health status. The questionnaire will be distributed three times during the study. The first measurement will be two weeks before surgery and represent the baseline. The questionnaire is distributed again at 2 months and 6 months after surgery and changes from baseline will be measured and compared between groups.	Measured at 2 weeks before surgery, 2 months after surgery and 6 months after surgery surgery
Patient reported outcome - RAND-36 questionnaire	Rand-36 is the Norwegian translation of the SF-36 version 1.2. The questionnaire consists of 36 items, grouped into eight multi-item scales that measure physical functioning, role limitations due to physical problems, bodily pain, general health, vitality, social functioning, role limitations due to emotional problems and mental health. The scores can also be summarized into two summary scores for overall physical and mental health. Items scores will be transformed to 0-100 point scales (0=worst, 100=best) using the SF-36 scoring algorithm The questionnaire will be distributed three times during the study. The first measurement will be two weeks before surgery and represent the baseline. The questionnaire is distributed again at 2 months and 6 months after surgery and changes from baseline will be measured and compared between groups.	Measured at 2 weeks before surgery, 2 months after surgery and 6 months after surgery surgery
Abscence from work	Days with sick-leave from work the first year after surgery. Data collected from the Norwegian national sick-leave registry	Measured at18 months after surgery

Collaborators and Investigators

• Sponsor: University Hospital of North Norway
• Collaborators: SINTEF Health Research; Helse Nord; Helseapps; Norinnova

Publications and helpful links

General Publications

• Brun VH, Eriksen AH, Selseth R, Johansson K, Vik R, Davidsen B, Kaut M, Hellemo L. Patient-Tailored Levothyroxine Dosage with Pharmacokinetic/Pharmacodynamic Modeling: A Novel Approach After Total Thyroidectomy. Thyroid. 2021 Sep;31(9):1297-1304. doi: 10.1089/thy.2021.0125. Epub 2021 Jun 22.

Study record dates

Study Major Dates

• Study Start (Actual): December 20, 2024
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: January 10, 2024
• First Submitted That Met QC Criteria: June 6, 2024
• First Posted (Actual): June 12, 2024

Study Record Updates

• Last Update Posted (Estimated): September 10, 2025
• Last Update Submitted That Met QC Criteria: September 3, 2025
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: thyroidectomy; levothyroxine; Decision support tool; Patient-centered dosage
• Additional Relevant MeSH Terms: Endocrine System Diseases; Neoplasms by Site; Neoplasms; Endocrine Gland Neoplasms; Head and Neck Neoplasms; Thyroid Diseases; Thyroid Neoplasms; Hypothyroidism
• Other Study ID Numbers: 547311

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No