{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T16:36:11Z","timestamp":1791995771659,"version":"4.4.0"},"reference-count":51,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,3,10]],"date-time":"2025-03-10T00:00:00Z","timestamp":1741564800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000062","name":"National Institute of Diabetes and Digestive and Kidney Diseases","doi-asserted-by":"publisher","award":["1R21DK122310-01A, 1R01DK140455-01"],"award-info":[{"award-number":["1R21DK122310-01A, 1R01DK140455-01"]}],"id":[{"id":"10.13039\/100000062","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Endocrinol."],"abstract":"\n Context<\/jats:title>\n Despite normalization of Thyrotropin (TSH), some patients with hypothyroidism treated with Levothyroxine (LT4) report residual symptoms which may be attributable to loss of endogenous triiodothyronine (T3).<\/jats:p>\n <\/jats:sec>\n \n Objective<\/jats:title>\n Feasibility trial LT4\/liothyronine (LT3) combination vs. LT4\/placebo in post-surgical hypothyroidism.<\/jats:p>\n <\/jats:sec>\n \n Design<\/jats:title>\n Double-blind, placebo-controlled, 24-week study.<\/jats:p>\n <\/jats:sec>\n \n Setting<\/jats:title>\n Academic medical center<\/jats:p>\n <\/jats:sec>\n \n Patients<\/jats:title>\n Individuals with indications for total thyroidectomy and replacement therapy.<\/jats:p>\n <\/jats:sec>\n \n Interventions<\/jats:title>\n LT4\/LT3 5 mcg (twice daily) vs. LT4\/placebo (twice daily). LT4 was adjusted at 6- and 12-weeks with the goal of baseline TSH \u00b1 0.5 mcIU\/ml.<\/jats:p>\n <\/jats:sec>\n \n Main Outcome Measures<\/jats:title>\n Changes in body weight, cholesterol, TSH, total T3, free tetraiodothyronine (T4). Cardiovascular function, energy expenditure, and quality of life (ThyPRO-39) were assessed in patients who completed at least the 3-month visit, last measure carried-forward.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n Twelve patients (10 women and 2 men), age 51 \u00b1 13.8 years (7 LT4\/placebo, 5 LT4\/LT3), were analyzed. No significant differences were observed in TSH. Following thyroidectomy, LT4\/placebo resulted in higher free T4 + 0.26 \u00b1 0.15 p&lt;0.005 and lower total T3 -18 \u00b1 9.6 ng\/dl p&lt;0.003, respectively, not observed in the LT4\/LT3 group. The LT4\/placebo group had a non-significant increase in body weight, +1.7 \u00b1 3.8 Kg, total- and LDL-cholesterol +43.1 \u00b1 72.8 and +32.0 \u00b1 64.4 mg\/dl. Conversely the LT4\/LT3 group changes were -0.6 \u00b1 1.9 Kg, -28.8 \u00b1 49.0 and -19.0 \u00b1 28.3 mg\/dl, respectively, all non-significant. Non-significant improvement were observed in ThyPRO-39 measures in both groups, while energy expenditure, and diastolic function increased in the LT4\/LT3 group.<\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n In this group of patients with post-surgical hypothyroidism LT4 replacement alone does not normalize free T4 and total T3 levels and is associated with non-significant increase in weight and cholesterol. LT4\/LT3 combination therapy appears to prevent these changes.<\/jats:p>\n <\/jats:sec>\n \n Clinical Trial Registration<\/jats:title>\n \n Clinicatrials.gov<\/jats:uri>\n , identifier NCT05682482.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fendo.2025.1522753","type":"journal-article","created":{"date-parts":[[2025,3,10]],"date-time":"2025-03-10T01:14:52Z","timestamp":1741569292000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":9,"title":["A feasibility double-blind trial of levothyroxine vs. levothyroxine-liothyronine in postsurgical hypothyroidism"],"prefix":"10.3389","volume":"16","author":[{"given":"Giao Q.","family":"Phan","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sahzene","family":"Yavuz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angeliki 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