Association between thyroid disease and mood disorders
Thyroid hormones influence the brain and other organs. Patients with thyroid dysfunction may often complain that they have mood and cognitive problems. An association between thyroid function and mood disorders has been described by the physician C. H. Parry as early as 1825.43 Modern imaging techniques suggest that both hypothyroidism and hyperthyroidism can lead to mood disorders and cognitive impairment.43 The mechanisms behind it, however, still remain unclear and the association is a matter of debate.
Thyroid hormones play a crucial role in the brain development of a fetus. In the adult brain they modulate the metabolic activity. Underproduction of thyroid hormones (hypothyroidism) can cause similar structural and functional alterations in the brain as is seen in major depression.44 In hyperthyroidism, where too many thyroid hormones are present, measurable changes in psychiatric and neuropsychological function are observed.45
- 43Hage MP and Azar ST. The Link between Thyroid Function and Depression. J Thyroid Research 2012; 2012: 590648 doi: 10.1155/2012/590648
- 44Pilhatsch M, Marxen M, Winter C et al. Hypothyroidism and mood disorders: Integrating novel insights from brain maging techniques. Thyroid Research 2011; 4 (1): 53. Full text available:http://www.thyroidresearchjournal.com/content/4/S1/S3 Accessed January 2014
- 45The American Thyroid Association and American Association of Clinical Endocrinologists Taskforce. Hyperthyroidism and Other Causes of Thyrotoxicosis: Management Guidelines of the American Thyroid Association and American Association of Clinical Endocrinologists. Thyroid 2011; 21 (6): 593- 641