Anti-thyroid Antibodies in Bipolar Disorder

Abstract

Background

Dysfunction of the hypothalamus-pituitary-thyroid axis has been shown to play a role in the pathophysiology of bipolar disorder. Autoimmune thyroiditis is the most common cause of thyroid function alteration. Thus, auto-immune thyroiditis is likely associated with bipolar disorder. It might influence its course, prognosis and/or management.

Objective

To study the prevalence of positive anti-thyroid antibodies in patients with bipolar disorder and to examine the prognostic and the therapeutic implications of their presence.

Methods

Literature was reviewed using the Medline database and the following keywords: ‘bipolar disorder” ‘antithyroid antibodies” ‘thyroiditis”.

Results

PubMed research returned 12 results. After manual inspection, 10 articles were retained and examined.

The prevalence of positive antithyroperoxydase antibodies (anti-TPO Abs) is higher in bipolar patients than in healthy controls, reaching 27%. The presence of positive anti-TPO Abs has been associated with rapid-cycling, with a higher risk of lithium-induced hypothyroidism as well as with poor prognosis.

Auto-immune thyroiditis appears to be related not only to bipolar disorder itself but also to the genetic vulnerability to develop the disorder.

Conclusion

The presence of anti-TPO Abs is a possible endophenotype for bipolar disorder. Anti-TPO Abs should be obtained in many patients with bipolar disorder, especially in those on lithium.