Editing Hyperthyroidism (section)

===Subclinical===
{{See also|Symptoms and signs of Graves' disease#Subclinical hyperthyroidism}}
In overt primary hyperthyroidism, TSH levels are low and T<sub>4</sub> and T<sub>3</sub> levels are high. Subclinical hyperthyroidism is a milder form of hyperthyroidism characterized by low or undetectable serum TSH level, but with a normal serum free thyroxine level.<ref>{{cite journal | vauthors = Biondi B, Cooper DS | title = The clinical significance of subclinical thyroid dysfunction | journal = Endocrine Reviews | volume = 29 | issue = 1 | pages = 76–131 | date = February 2008 | pmid = 17991805 | doi = 10.1210/er.2006-0043 | doi-access = free }}</ref> Although the evidence for doing so is not definitive, treatment of elderly persons having subclinical hyperthyroidism could reduce the number of cases of [[atrial fibrillation]].<ref>{{cite journal | vauthors = Surks MI, Ortiz E, Daniels GH, Sawin CT, Col NF, Cobin RH, Franklyn JA, Hershman JM, Burman KD, Denke MA, Gorman C, Cooper RS, Weissman NJ | title = Subclinical thyroid disease: scientific review and guidelines for diagnosis and management | journal = JAMA | volume = 291 | issue = 2 | pages = 228–238 | date = January 2004 | pmid = 14722150 | doi = 10.1001/jama.291.2.228 }}</ref> There is also an increased risk of [[bone fracture]]s (by 42%) in people with subclinical hyperthyroidism; there is insufficient evidence to say whether treatment with antithyroid medications would reduce that risk.<ref>{{cite journal | vauthors = Blum MR, Bauer DC, Collet TH, Fink HA, Cappola AR, da Costa BR, Wirth CD, Peeters RP, Åsvold BO, den Elzen WP, Luben RN, Imaizumi M, Bremner AP, Gogakos A, Eastell R, Kearney PM, Strotmeyer ES, Wallace ER, Hoff M, Ceresini G, Rivadeneira F, Uitterlinden AG, Stott DJ, Westendorp RG, Khaw KT, Langhammer A, Ferrucci L, Gussekloo J, Williams GR, Walsh JP, Jüni P, Aujesky D, Rodondi N | title = Subclinical thyroid dysfunction and fracture risk: a meta-analysis | journal = JAMA | volume = 313 | issue = 20 | pages = 2055–2065 | date = May 2015 | pmid = 26010634 | pmc = 4729304 | doi = 10.1001/jama.2015.5161 }}</ref>

A 2022 meta-analysis found subclinical hyperthyroidism to be associated with cardiovascular death.<ref>{{cite journal |last1=Müller |first1=P |last2=Leow |first2=MK |last3=Dietrich |first3=JW |title=Minor perturbations of thyroid homeostasis and major cardiovascular endpoints-Physiological mechanisms and clinical evidence. |journal=Frontiers in Cardiovascular Medicine |date=2022 |volume=9 |pages=942971 |doi=10.3389/fcvm.2022.942971 |pmid=36046184|pmc=9420854 |doi-access=free }}</ref>