15 Little Known Things About Your Thyroid That Can Affect Your Mental Health

Ever wondered if your thyroid gland is playing a role in your depression, anxiety or psychosis? Problems with your Thyroid gland can mimic a number of psychiatric disorders ranging from depression, anxiety and even psychosis. It is thus extremely important that mental health professionals be aware of some important but little known facts.

1. The brain has amongst the highest expression of thyroid hormone receptors of any organ and neurons are often more sensitive to thyroid abnormalities than other cells.
2. TSH levels have a circadian rhythm; the most accurate measurement is obtained in the morning before 9 am.
3. Psychiatrists may be the first professionals that hypo/hyperthyroid patients may consult due to point 1.
4. Affective spectrum disorders are most common.
5. Panic disorder can precede Graves disease by 4-5 years in some cases.
6. Increased prolactin may be a clue to hypothyroidism and not just attributable to antipsychotics.
7. T3 is the active hormone and the conversion from T4 to T3 requires selenium.
8. Iodine deficiency and Autoimmune thyroiditis are common causes of hypothyroidism.
9. TSH > 3.0 requires follow up and clinical correlation.
10. Increased antithyroid antibody titres have been linked with psychotic and depressive syndromes in Borderline personality disorder.
11. Antithyroid antibodies are associated with increased risk of developing frank or subclinical hypothyroidism.
12. Autoimmune thyroiditis is an endophenotype of bipolar disorder (both conditions may have the same genetic origin) and can be present independent of lithium use.
13. Supraphysiological dose of thyroxine in bipolar disorder may convert a non responder to mood stabilizer to a responder.
14. Transthyretin (TTR), a carrier protein for thyroxine and retinol in plasma and cerebrospinal fluid (CSF), has been shown to bind the amyloid beta peptide and reduced levels of transthyretin are found in alzheimer’s disease.
15. TSH levels on their own may not accurately describe thyroid dysfunction.  Circulating T3, Free T3 or free T4 levels near the margin of normal range and or TSH > 3.5 -4.0 mIU/ml may be indications for prescribing thyroid replacement.

In an earlier post we covered the role of thyroid gland in psychiatry and why the TSH may not be an accurate indicator. History taking and examination of the thyroid gland is an integral part of psychiatric evaluation and can’t be ignored. We covered it as part of the physical examinations in psychinterview.com.

I’d like to hear how commonly you find psychiatric patients with thyroid dysfunction and how you manage it.

References:

1. Geracioti, T. D. (2006). Identifying hypothyroidism’s psychiatric presentations. Current Psychiatry, 5(11), 98.
2. Sakurai, A., Nakai, A., & DeGroot, L. J. (1989). Expression of three forms of thyroid hormone receptor in human tissues. Molecular Endocrinology, 3(2), 392-399.
3. Sousa, J. C., Cardoso, I., Marques, F., Saraiva, M. J., & Palha, J. A. (2007). Transthyretin and Alzheimer’s disease: Where in the brain?. Neurobiology of aging, 28(5), 713-718.

This article is written by Dr Sanil Rege. Sanil is a Consultant Psychiatrist on the Mornington Peninsula and co-founder of psychscene.com. He is pursuing an MBA at the Melbourne Business School.  You can follow him on Google+