{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T14:16:17Z","timestamp":1784556977432,"version":"3.55.0"},"reference-count":54,"publisher":"Bioscientifica","issue":"10","license":[{"start":{"date-parts":[[2018,10,1]],"date-time":"2018-10-01T00:00:00Z","timestamp":1538352000000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":["ec.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2018,10]]},"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Season of birth, an exogenous indicator of early life environment, has been linked with a higher risk of adverse health outcomes such as autoimmune thyroiditis, multiple sclerosis and schizophrenia later in life. Whether the development and cause of hyperthyroidism is influenced by season of birth is unclarified. We aimed, at a nationwide level, to investigate whether season of birth influences the risk of hyperthyroidism due to Graves\u2019 disease (GD) and\/or toxic nodular goitre (TNG).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Method<\/jats:title>\n                    <jats:p>Register-based nationwide cohort study. By record-linkage between Danish health registers, 36,087 and 20,537 patients with GD and TNG, respectively, were identified. Each case was matched with four controls without thyroid disease, according to age and sex. Differences in month of birth across the year were evaluated by the Walter\u2013Elwood test. Hazard ratios, for the risk of GD and TNG in individuals born in a certain month or season of the year, were calculated using Cox regression models.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Neither for GD nor for TNG could we demonstrate a significant difference in birth rate across months or seasons of the year (Walter\u2013Elwood\u2019s test; X\n                      <jats:sup>2<\/jats:sup>\n                      \u2009=\u20095.92 and X\n                      <jats:sup>2<\/jats:sup>\n                      \u2009=\u20091.27,\n                      <jats:italic>P<\/jats:italic>\n                      \u2009=\u20090.052 and\n                      <jats:italic>P<\/jats:italic>\n                      \u2009=\u20090.53, respectively).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Irrespective of its cause, our findings do not support the hypothesis that season of birth is significantly related to the development of hyperthyroidism.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1530\/ec-18-0185","type":"journal-article","created":{"date-parts":[[2018,8,24]],"date-time":"2018-08-24T11:55:27Z","timestamp":1535111727000},"page":"1090-1095","update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-10","source":"Crossref","is-referenced-by-count":5,"title":["No link between season of birth and subsequent development of Graves\u2019 disease or toxic nodular goitre. A nationwide Danish register-based study"],"prefix":"10.1530","volume":"7","author":[{"given":"Suvanjaa","family":"Sivalingam","sequence":"first","affiliation":[{"name":"1Department of Internal Medicine, Hospital of Southern Jutland, S\u00f8nderborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marianne","family":"Thvilum","sequence":"additional","affiliation":[{"name":"2Department of Endocrinology and Metabolism, Odense University Hospital, Odense C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas Heiberg","family":"Brix","sequence":"additional","affiliation":[{"name":"2Department of Endocrinology and Metabolism, Odense University Hospital, Odense C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laszlo","family":"Heged\u00fcs","sequence":"additional","affiliation":[{"name":"2Department of Endocrinology and Metabolism, Odense University Hospital, Odense C, Denmark"},{"name":"3Department of Clinical Research, University of Southern Denmark, Odense M, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frans","family":"Brandt","sequence":"additional","affiliation":[{"name":"1Department of Internal Medicine, Hospital of Southern Jutland, S\u00f8nderborg, Denmark"},{"name":"4Department of Regional Health Research, University of Southern Denmark, Odense M, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"416","reference":[{"key":"ref01","first-page":"1552","article-title":"Graves\u2019 disease","volume-title":"New England Journal of Medicine","volume":"375","year":"2016"},{"key":"ref201","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1177\/1403494811399956","article-title":"Introduction to Danish (nationwide) registers on health and social issues: structure, access, legislation, and archiving","volume":"39","year":"2011","journal-title":"Scandinavian Journal of Public 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disease","volume":"123","year":"2010","journal-title":"American Journal of Medicine"},{"key":"ref451","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1530\/EJE-07-0015","article-title":"Seasonality of month of birth of patients with Graves\u2019 and Hashimoto\u2019s diseases differ from that in the general population","volume":"156","year":"2007","journal-title":"European Journal of Endocrinology"},{"key":"ref101","first-page":"50","article-title":"Environmental issues in thyroid diseases","volume":"8","year":"2017","journal-title":"Frontiers in Endocrinology"},{"key":"ref521","doi-asserted-by":"crossref","first-page":"1164","DOI":"10.1038\/ejhg.2008.106","article-title":"Gene-environment interactions for complex traits: definitions, methodological requirements and challenges","volume":"16","year":"2008","journal-title":"European Journal of Human 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A nationwide Danish register-based study","volume":"87","year":"2017","journal-title":"Clinical Endocrinology"},{"key":"ref361","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1007\/BF03345276","article-title":"Relationship between cigarette smoking and Graves\u2019 ophthalmopathy","volume":"27","year":"2004","journal-title":"Journal of Endocrinological Investigation"},{"key":"ref241","doi-asserted-by":"crossref","first-page":"1164","DOI":"10.1038\/ejhg.2008.106","article-title":"Gene-environment interactions for complex traits: definitions, methodological requirements and challenges","volume":"16","year":"2008","journal-title":"European Journal of Human Genetics"},{"key":"ref541","first-page":"1","article-title":"Prevalence and relative risk of other autoimmune diseases in subjects with autoimmune thyroid disease","volume":"123","year":"2010","journal-title":"American Journal of 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gland","volume":"37","year":"1988","journal-title":"Metabolism"},{"key":"ref351","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1111\/cen.12106","article-title":"Graves\u2032 hyperthyroidism and moderate alcohol consumption: evidence for disease prevention","volume":"79","year":"2013","journal-title":"Clinical Endocrinology"},{"key":"ref401","doi-asserted-by":"crossref","first-page":"491","DOI":"10.1111\/j.1365-2265.2008.03227.x","article-title":"Too early to dismiss Yersinia enterocolitica infection in the aetiology of Graves\u2019 disease: evidence from a twin case-control study","volume":"69","year":"2008","journal-title":"Clinical Endocrinology"},{"key":"ref371","first-page":"661","article-title":"Cigarette smoking and risk of clinically overt thyroid disease: a population-based twin case-control study","volume":"160","year":"2000","journal-title":"Archives of Internal 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Autoimmunity"},{"key":"ref11","doi-asserted-by":"crossref","first-page":"906","DOI":"10.1016\/S0140-6736(16)00278-6","article-title":"Hyperthyroidism","volume":"388","year":"2016","journal-title":"Lancet"},{"key":"ref81","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1007\/BF03345276","article-title":"Relationship between cigarette smoking and Graves\u2019 ophthalmopathy","volume":"27","year":"2004","journal-title":"Journal of Endocrinological Investigation"},{"key":"ref471","first-page":"51","article-title":"Seasonal variations in the diagnosis of hyperthyroidism","volume":"27","year":"2000","journal-title":"Acta Medica Austriaca"},{"key":"ref281","first-page":"1552","article-title":"Graves\u2019 disease","volume-title":"New England Journal of Medicine","volume":"375","year":"2016"},{"key":"ref71","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1111\/cen.12106","article-title":"Graves\u2032 hyperthyroidism and moderate alcohol consumption: evidence for disease prevention","volume":"79","year":"2013","journal-title":"Clinical Endocrinology"},{"key":"ref131","doi-asserted-by":"crossref","first-page":"832","DOI":"10.1111\/cen.13425","article-title":"Month of birth is associated with the subsequent diagnosis of autoimmune hypothyroidism. A nationwide Danish register-based study","volume":"87","year":"2017","journal-title":"Clinical Endocrinology"},{"key":"ref171","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1530\/EJE-07-0015","article-title":"Seasonality of month of birth of patients with Graves\u2019 and Hashimoto\u2019s diseases differ from that in the general population","volume":"156","year":"2007","journal-title":"European Journal of Endocrinology"},{"key":"ref481","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1177\/1403494811399956","article-title":"Introduction to Danish (nationwide) registers on health and social issues: structure, access, legislation, and archiving","volume":"39","year":"2011","journal-title":"Scandinavian Journal of Public Health"},{"key":"ref311","doi-asserted-by":"crossref","first-page":"457","DOI":"10.1111\/j.1365-2265.2011.04318.x","article-title":"Twin studies as a model for exploring the aetiology of autoimmune thyroid disease","volume":"76","year":"2012","journal-title":"Clinical Endocrinology"},{"key":"ref121","doi-asserted-by":"crossref","first-page":"491","DOI":"10.1111\/j.1365-2265.2008.03227.x","article-title":"Too early to dismiss Yersinia enterocolitica infection in the aetiology of Graves\u2019 disease: evidence from a twin case-control study","volume":"69","year":"2008","journal-title":"Clinical Endocrinology"},{"key":"ref161","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/j.jaut.2017.06.001","article-title":"Seasonality and autoimmune diseases: the contribution of the four seasons to the mosaic of autoimmunity","volume":"82","year":"2017","journal-title":"Journal of Autoimmunity"},{"key":"ref331","first-page":"930","article-title":"Evidence for a major role of heredity in Graves\u2019 disease: a population-based study of two Danish twin cohorts","volume":"86","year":"2001","journal-title":"Journal of Clinical Endocrinology and Metabolism"},{"key":"ref381","first-page":"50","article-title":"Environmental issues in thyroid diseases","volume":"8","year":"2017","journal-title":"Frontiers in Endocrinology"}],"container-title":["Endocrine Connections"],"original-title":[],"link":[{"URL":"https:\/\/ec.bioscientifica.com\/view\/journals\/ec\/7\/10\/EC-18-0185.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/ec.bioscientifica.com\/downloadpdf\/journals\/ec\/7\/10\/EC-18-0185.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T13:42:56Z","timestamp":1784554976000},"score":1,"resource":{"primary":{"URL":"http:\/\/journals.bioscientifica.com\/ec\/article\/7\/10\/1090-1095\/365"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,10]]},"references-count":54,"journal-issue":{"issue":"10"},"URL":"https:\/\/doi.org\/10.1530\/ec-18-0185","relation":{},"ISSN":["2049-3614"],"issn-type":[{"value":"2049-3614","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,10]]}}}