{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T05:44:42Z","timestamp":1791783882929,"version":"4.3.4"},"reference-count":20,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,10,11]],"date-time":"2026-10-11T00:00:00Z","timestamp":1791676800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2026,10,11]],"date-time":"2026-10-11T00:00:00Z","timestamp":1791676800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Clinical Endocrinology"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>Thyroid dysfunction has been increasingly reported after the coronavirus disease 2019 (COVID\u201019) pandemic. To date, no population\u2010based study has examined this association using more than 10 million matched pairs. We compared the risk of documented thyroid outcomes after COVID\u201019 with that after influenza during the Omicron\u2010predominant period.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a nationwide retrospective cohort study using the Japanese National Database of Health Insurance Claims, including patients with COVID\u201019 between January 2022 and March 2023, and those with influenza between September 2017 and March 2023. Individuals with pre\u2010existing thyroid disease were excluded. After 1:1 propensity score matching, 24,173,646 pairs were analysed. Database\u2010recorded outcomes assessed within 90 days of documented COVID\u201019 infection included diagnoses of thyrotoxicosis, hypothyroidism and subacute thyroiditis, as well as initiation of antithyroid drugs (ATDs) and thyroid hormone replacement therapy (THRT).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among database\u2010recorded outcomes, COVID\u201019 was associated with higher risks of thyrotoxicosis diagnosis (risk ratio [RR], 1.08), hypothyroidism diagnosis (RR, 1.12), ATD initiation (RR, 1.06) and THRT initiation (RR, 1.22) than influenza, but not subacute thyroiditis diagnosis. Age\u2010stratified analyses showed markedly higher risks in individuals aged 0\u201319 years for thyrotoxicosis diagnosis (RR, 1.38) and ATD initiation (RR, 1.77).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In this nationwide cohort, COVID\u201019 was associated with higher risks of database\u2010recorded diagnoses of thyrotoxicosis and hypothyroidism than influenza during the Omicron\u2010predominant period. The strongest association was observed for thyrotoxicosis diagnosis and ATD initiation in younger individuals, underscoring the importance of post\u2013COVID\u201019 thyroid monitoring in adolescents and young adults.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1111\/cen.70217","type":"journal-article","created":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T04:47:09Z","timestamp":1791780429000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Increased Risk of Thyrotoxicosis After COVID\u201019 in Adolescents and Young Adults During the Omicron\u2010Predominant Period: A Nationwide Matched Study"],"prefix":"10.1111","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3550-1182","authenticated-orcid":false,"given":"Koichi","family":"Miyashita","sequence":"first","affiliation":[{"name":"Second Division, Department of Internal Medicine Hamamatsu University School of Medicine Hamamatsu Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8538-8742","authenticated-orcid":false,"given":"Kenji","family":"Ohba","sequence":"additional","affiliation":[{"name":"Second Division, Department of Internal Medicine Hamamatsu University School of Medicine Hamamatsu Japan"},{"name":"Medical Education Center Hamamatsu University School of Medicine Hamamatsu Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5439-1543","authenticated-orcid":false,"given":"Hironao","family":"Hozumi","sequence":"additional","affiliation":[{"name":"Second Division, Department of Internal Medicine Hamamatsu University School of Medicine Hamamatsu Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4079-5509","authenticated-orcid":false,"given":"Kazuki","family":"Furuhashi","sequence":"additional","affiliation":[{"name":"Second Division, Department of Internal Medicine Hamamatsu University School of Medicine Hamamatsu Japan"},{"name":"Infection Control and Prevention Center Hamamatsu University School of Medicine Hamamatsu Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8809-1781","authenticated-orcid":false,"given":"Tomoyuki","family":"Fujisawa","sequence":"additional","affiliation":[{"name":"Second Division, Department of Internal Medicine Hamamatsu University School of Medicine Hamamatsu Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4624-7119","authenticated-orcid":false,"given":"Naoki","family":"Inui","sequence":"additional","affiliation":[{"name":"Second Division, Department of Internal Medicine Hamamatsu University School of Medicine Hamamatsu Japan"},{"name":"Department of Clinical Pharmacology and Therapeutics Hamamatsu University School of Medicine Hamamatsu Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6888-0698","authenticated-orcid":false,"given":"Toshiyuki","family":"Ojima","sequence":"additional","affiliation":[{"name":"Community Health and Preventive Medicine Hamamatsu University School of Medicine Hamamatsu Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5300-0504","authenticated-orcid":false,"given":"Takafumi","family":"Suda","sequence":"additional","affiliation":[{"name":"Second Division, Department of Internal Medicine Hamamatsu University School of Medicine Hamamatsu Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,10,11]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1038\/s41574-023-00946-w","article-title":"Thyroid Dysfunction in COVID\u201019","volume":"20","author":"Lui D. T. W.","year":"2024","journal-title":"Nature Reviews Endocrinology"},{"key":"e_1_2_8_3_1","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1530\/EJE-20-0335","article-title":"Thyrotoxicosis in Patients With COVID\u201019: The THYRCOV Study","volume":"183","author":"Lania A.","year":"2020","journal-title":"European Journal of Endocrinology"},{"key":"e_1_2_8_4_1","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1016\/j.eprac.2023.01.011","article-title":"Increased Incidence and Severity of New Graves Disease Diagnoses in Youth During the COVID\u201019 Pandemic","volume":"29","author":"Donner J. R.","year":"2023","journal-title":"Endocrine Practice"},{"key":"e_1_2_8_5_1","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1530\/EJE-20-1391","article-title":"The Spectrum of Thyroid Function Tests During Hospitalization for SARS\u2010CoV\u20102 Infection","volume":"184","author":"Campi I.","year":"2021","journal-title":"European Journal of Endocrinology"},{"key":"e_1_2_8_6_1","doi-asserted-by":"crossref","DOI":"10.3389\/fendo.2021.708333","article-title":"Coronavirus Disease 2019 and the Thyroid: Progress and Perspectives","volume":"12","author":"Inaba H.","year":"2021","journal-title":"Frontiers in Endocrinology"},{"key":"e_1_2_8_7_1","doi-asserted-by":"crossref","DOI":"10.3389\/fendo.2025.1535169","article-title":"Thyroid Disorders and COVID\u201019: A Comprehensive Review of Literature","volume":"16","author":"Anbardar N.","year":"2025","journal-title":"Frontiers in Endocrinology"},{"key":"e_1_2_8_8_1","doi-asserted-by":"crossref","DOI":"10.3389\/fendo.2024.1477389","article-title":"Thyroid Function During COVID\u201019 and Post\u2010COVID Complications in Adults: A Systematic Review","volume":"15","author":"Panesar A.","year":"2025","journal-title":"Frontiers in Endocrinology"},{"key":"e_1_2_8_9_1","doi-asserted-by":"crossref","first-page":"528","DOI":"10.1016\/j.eprac.2024.03.389","article-title":"Risk of Incident Thyroid Dysfunction in the Post\u2010Acute Phase of COVID\u201019: A Population\u2010Based Cohort Study in Hong Kong","volume":"30","author":"Lui D. T. W.","year":"2024","journal-title":"Endocrine Practice"},{"key":"e_1_2_8_10_1","first-page":"442","article-title":"Association of COVID\u201019 Infection With Subsequent Thyroid Dysfunction: An International Population\u2010Based Propensity Score Matched Analysis","volume":"34","author":"Huang L. A.","year":"2024","journal-title":"Thyroid"},{"key":"e_1_2_8_11_1","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1016\/S2213-8587(22)00044-4","article-title":"Risks and Burdens of Incident Diabetes in Long COVID: A Cohort Study","volume":"10","author":"Xie Y.","year":"2022","journal-title":"Lancet Diabetes & Endocrinology"},{"key":"e_1_2_8_12_1","doi-asserted-by":"crossref","first-page":"2631","DOI":"10.1093\/aje\/kwae437","article-title":"Modern Sources of Controls in Case\u2010Control Studies","volume":"194","author":"Banack H. R.","year":"2025","journal-title":"American Journal of Epidemiology"},{"key":"e_1_2_8_13_1","doi-asserted-by":"crossref","first-page":"m4677","DOI":"10.1136\/bmj.m4677","article-title":"Comparative Evaluation of Clinical Manifestations and Risk of Death in Patients Admitted to Hospital With Covid\u201019 and Seasonal Influenza: Cohort Study","volume":"371","author":"Xie Y.","year":"2020","journal-title":"BMJ"},{"key":"e_1_2_8_14_1","doi-asserted-by":"crossref","first-page":"1697","DOI":"10.1001\/jama.2023.5348","article-title":"Risk of Death in Patients Hospitalized for COVID\u201019 vs Seasonal Influenza in Fall\u2010Winter 2022\u20132023","volume":"329","author":"Xie Y.","year":"2023","journal-title":"Journal of the American Medical Association"},{"key":"e_1_2_8_15_1","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1186\/s41479-025-00158-y","article-title":"Outcomes of COVID\u201019 in the Omicron\u2010Predominant Wave: Large\u2010Scale Real\u2010World Data Analysis With a Comparison to Influenza","volume":"17","author":"Miyashita K.","year":"2025","journal-title":"Pneumonia"},{"key":"e_1_2_8_16_1","doi-asserted-by":"crossref","first-page":"13","DOI":"10.37737\/ace.2.1_13","article-title":"A Review of Studies Using the Japanese National Database of Health Insurance Claims and Specific Health Checkups","volume":"2","author":"Hirose N.","year":"2020","journal-title":"Annals of Clinical Epidemiology"},{"key":"e_1_2_8_17_1","doi-asserted-by":"crossref","DOI":"10.1080\/22221751.2022.2155250","article-title":"Changes in the Characteristics and Outcomes of COVID\u201019 Patients From the Early Pandemic to the Delta Variant Epidemic: A Nationwide Population\u2010Based Study","volume":"12","author":"Miyashita K.","year":"2023","journal-title":"Emerging Microbes & Infections"},{"key":"e_1_2_8_18_1","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1507\/endocrj.50.429","article-title":"Prevalence and Clinico\u2010Epidemiology of Familial Graves' Disease in Japan Based on Nationwide Epidemiologic Survey in 2001","volume":"50","author":"Akamizu T.","year":"2003","journal-title":"Endocrine Journal"},{"key":"e_1_2_8_19_1","doi-asserted-by":"crossref","first-page":"1299","DOI":"10.1089\/thy.2022.0363","article-title":"Incidence of Subacute Thyroiditis During the COVID\u201019 Pandemic in South Korea Using the National Health Insurance Service Database","volume":"32","author":"Ahn H. Y.","year":"2022","journal-title":"Thyroid"},{"key":"e_1_2_8_20_1","doi-asserted-by":"crossref","first-page":"2938","DOI":"10.1210\/clinem\/dgaf023","article-title":"Subacute Thyroiditis\u2010Is It Really Linked to Viral Infection?","volume":"110","author":"Orth H. M.","year":"2025","journal-title":"Journal of Clinical Endocrinology & Metabolism"},{"key":"e_1_2_8_21_1","doi-asserted-by":"crossref","DOI":"10.1016\/j.beem.2023.101742","article-title":"COVID\u2010Induced Thyroid Autoimmunity","volume":"37","author":"Brancatella A.","year":"2023","journal-title":"Best Practice & Research Clinical Endocrinology & Metabolism"}],"container-title":["Clinical Endocrinology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/cen.70217","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1111\/cen.70217","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/cen.70217","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T04:47:24Z","timestamp":1791780444000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/cen.70217"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,10,11]]},"references-count":20,"alternative-id":["10.1111\/cen.70217"],"URL":"https:\/\/doi.org\/10.1111\/cen.70217","archive":["Portico"],"relation":{},"ISSN":["0300-0664","1365-2265"],"issn-type":[{"value":"0300-0664","type":"print"},{"value":"1365-2265","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,10,11]]},"assertion":[{"value":"2026-02-22","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-23","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-10-11","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"cen.70217"}}