{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T05:05:54Z","timestamp":1784264754074,"version":"3.55.0"},"reference-count":26,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T00:00:00Z","timestamp":1784246400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Endocrinol."],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>Radioactive iodine-131 (I-131) is a standard therapy for Graves\u2019 disease (GD), yet predicting therapeutic efficacy remains challenging due to complex biological variables. Conventional linear models often fail to capture the dynamic dose-response relationship between thyroid size and treatment outcomes. This study aimed to characterize the non-linear relationship between thyroid weight and I-131 efficacy and identify critical clinical thresholds influencing therapeutic success.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A retrospective multicenter cohort study was conducted involving 888 records, of whom 612 GD patients received initial I-131 treatment between 2018 and 2024. Thyroid weight was estimated using thyroid scintigraphy. Restricted cubic splines (RCS) were employed to model potential non-linear associations, and piecewise threshold analysis was utilized to determine optimal inflection points regarding the correlation between thyroid weight and treatment non-remission.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 612 patients (mean age 41.2 \u00b1 12.4 years; 73.9% female), 250 (40.8%) experienced non-remission after initial I-131 therapy. RCS analysis revealed a significant non-linear association between thyroid weight and treatment outcome in both unadjusted (P-nonlinear = 0.034) and DAG-confounder-adjusted models including study center (P-nonlinear = 0.032). In multivariable DAG-based logistic regression, thyroid weight (adjusted OR\u00a0=\u00a01.025, 95% CI: 1.017-1.034), female gender (adjusted OR\u00a0=\u00a01.67, 95% CI: 1.09-2.56), disease duration &amp;gt;2 years (adjusted OR\u00a0=\u00a01.97, 95% CI: 1.30-2.99), and study center (adjusted OR\u00a0=\u00a00.62, 95% CI: 0.42-0.93) were independent predictors. Piecewise analysis identified an exploratory inflection point at 46\u00a0g (adjusted LRT: P\u00a0=\u00a00.030). Mediation analysis demonstrated that RAIU at 3\u00a0h was a modest partial mediator (Sobel Z\u00a0=\u00a02.43, P\u00a0=\u00a00.015; mediated proportion: 5.8%).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Thyroid weight demonstrates a significant non-linear association with I-131 treatment efficacy in GD, with an exploratory inflection point at approximately 46\u00a0g. The association is robust to DAG-based confounder adjustment including study center and is only modestly mediated by radioiodine uptake. These findings support individualized RAI dosing strategies incorporating thyroid weight thresholds.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fendo.2026.1802163","type":"journal-article","created":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T04:23:12Z","timestamp":1784262192000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Non-linear association between thyroid scintigraphy-derived thyroid weight and I-131 treatment efficacy in graves\u2019 disease: a multicenter restricted cubic spline and threshold analysis"],"prefix":"10.3389","volume":"17","author":[{"given":"Lu","family":"Lu","sequence":"first","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"LeLe","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, First Affiliated Hospital of Guilin Medical University","place":["Guilin, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dongyun","family":"Meng","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaojuan","family":"Wei","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaozhou","family":"Mo","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zeyong","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fengyang","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuehua","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xingyu","family":"Mu","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, First Affiliated Hospital of Guilin Medical University","place":["Guilin, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wentan","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Fu","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, First Affiliated Hospital of Guilin Medical University","place":["Guilin, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kehua","family":"Liao","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, The People\u2019s Hospital of Guangxi Zhuang Autonomous Region","place":["Nanning, Guangxi Zhuang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,17]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.5603\/NMR.2015.0026","article-title":"Diagnosis and treatment of graves\u2019 disease with particular emphasis on appropriate techniques in nuclear medicine. general state of knowledge","volume":"18","author":"Prasek","year":"2015","journal-title":"Nucl Med Rev"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.55070\/137w7361","article-title":"Graves disease - a comprehensive 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