Central hypothyroidism is rare and accounts for less than 1% of hypothyroid cases.[2]Chaker L, Bianco AC, Jonklaas J, et al. Hypothyroidism. Lancet. 2017 Sep 23;390(10101):1550-62.
http://www.ncbi.nlm.nih.gov/pubmed/28336049?tool=bestpractice.com
It most frequently occurs as a sporadic form of hypothyroidism and can affect patients of all ages, with no sex predominance.[1]Beck-Peccoz P, Rodari G, Giavoli C, et al. Central hypothyroidism: a neglected thyroid disorder. Nat Rev Endocrinol. 2017 Oct;13(10):588-98.
http://www.ncbi.nlm.nih.gov/pubmed/28549061?tool=bestpractice.com
[3]Persani L, Brabant G, Dattani M, et al. 2018 European Thyroid Association (ETA) guidelines on the diagnosis and management of central hypothyroidism. Eur Thyroid J. 2018 Oct;7(5):225-37.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6198777
http://www.ncbi.nlm.nih.gov/pubmed/30374425?tool=bestpractice.com
The prevalence of central hypothyroidism ranges from 1 in 16,000 to about 1 in 100,000 in the general adult or neonatal populations.[3]Persani L, Brabant G, Dattani M, et al. 2018 European Thyroid Association (ETA) guidelines on the diagnosis and management of central hypothyroidism. Eur Thyroid J. 2018 Oct;7(5):225-37.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6198777
http://www.ncbi.nlm.nih.gov/pubmed/30374425?tool=bestpractice.com
Variability in worldwide prevalence data can mostly be attributed to differences in screening programs.[1]Beck-Peccoz P, Rodari G, Giavoli C, et al. Central hypothyroidism: a neglected thyroid disorder. Nat Rev Endocrinol. 2017 Oct;13(10):588-98.
http://www.ncbi.nlm.nih.gov/pubmed/28549061?tool=bestpractice.com
For example, if thyroid-stimulating hormone (TSH) levels are measured in isolation, congenital central hypothyroidism is often undiagnosed, as it is most typically associated with low to normal levels of circulating TSH with concomitantly low levels of free thyroxine.[1]Beck-Peccoz P, Rodari G, Giavoli C, et al. Central hypothyroidism: a neglected thyroid disorder. Nat Rev Endocrinol. 2017 Oct;13(10):588-98.
http://www.ncbi.nlm.nih.gov/pubmed/28549061?tool=bestpractice.com
Pituitary adenomas are the most common cause of central hypothyroidism. Secreting adenomas (prolactinomas), growth hormone-secreting adenomas, and nonsecretory adenomas account for more than half of the cases.[4]Persani L. Clinical review: central hypothyroidism: pathogenic, diagnostic, and therapeutic challenges. J Clin Endocrinol Metab. 2012 Sep;97(9):3068-78.
https://academic.oup.com/jcem/article/97/9/3068/2536827
http://www.ncbi.nlm.nih.gov/pubmed/22851492?tool=bestpractice.com