{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:34:32Z","timestamp":1787027672231,"version":"build-2736575974"},"reference-count":27,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,6,14]],"date-time":"2023-06-14T00:00:00Z","timestamp":1686700800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Graz University of Technology"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Hypothyroidism is a condition where the patient\u2019s thyroid gland cannot produce sufficient thyroid hormones (mainly triiodothyronine and thyroxine). The primary cause of hypothyroidism is autoimmune-mediated destruction of the thyroid gland, referred to as Hashimoto\u2019s thyroiditis. A patient\u2019s desired thyroid hormone concentration is achieved by oral administration of thyroid hormone, usually levothyroxine. Establishing individual levothyroxine doses to achieve desired thyroid hormone concentrations requires several patient visits. Additionally, clear guidance for the dosing regimen is lacking, and significant inter-individual differences exist. This study aims to design a digital automatic dosing algorithm for patients suffering from Hashimoto\u2019s thyroiditis. The dynamic behaviour of the relevant thyroid function is mathematically modelled. Methods of automatic control are exploited for the design of the proposed robust model-based levothyroxine dosing algorithm. Numerical simulations are performed to evaluate the mathematical model and the dosing algorithm. With the help of the developed controller thyroid hormone concentrations of patients, emulated using Thyrosim, have been regulated under the euthyroid state. The proposed concept demonstrates reliable responses amidst varying patient parameters. Our developed model provides a useful basis for the design of automatic levothyroxine dosing algorithms. The proposed robust feedback loop contributes to the first results for computer-assisted thyroid dosing algorithms.<\/jats:p>","DOI":"10.3390\/bioengineering10060724","type":"journal-article","created":{"date-parts":[[2023,6,15]],"date-time":"2023-06-15T02:28:56Z","timestamp":1686796136000},"page":"724","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Automatic Levothyroxine Dosing Algorithm for Patients Suffering from Hashimoto\u2019s Thyroiditis"],"prefix":"10.3390","volume":"10","author":[{"given":"Ravi","family":"Sharma","sequence":"first","affiliation":[{"name":"Institute of Automation and Control, Graz University of Technology, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Verena","family":"Theiler-Schwetz","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Trummer","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Pilz","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4681-9575","authenticated-orcid":false,"given":"Markus","family":"Reichhartinger","sequence":"additional","affiliation":[{"name":"Institute of Automation and Control, Graz University of Technology, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e2193","DOI":"10.1097\/MD.0000000000002193","article-title":"Gender and Age Impacts on the Association Between Thyroid Function and Metabolic Syndrome in Chinese","volume":"94","author":"Meng","year":"2015","journal-title":"Medicine"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1007\/s12325-019-01080-8","article-title":"Hypothyroidism in Context: Where We\u2019ve Been and Where We\u2019re Going","volume":"36","author":"Chiovato","year":"2019","journal-title":"Adv. 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