Evaluating Thyroid Status in Women with Polycystic Ovarian Syndrome (PCOS).

Women with PCOS at Increased Risk for Autoimmune Thyroid Disease

Polycystic ovarian syndrome (PCOS) is a common endocrine disorder that affects 10-20 % of women worldwide. We’ve reviewed the diagnostic criteria for PCOS in previous article. Many women with PCOS come to see a dermatologist for concerns related to androgenetic hair loss. In general, women with PCOS hav evidence of increased androgens (either via blood tests or via increased clinical finings ) and often have irregular periods. Ovarian ultrasound studies may show polycystic ovaries (with new criteria requiring 20 or more follicles per ovary or an ovarian volume of greater than 10 mL)

Polycystic ovarian syndrome has been associated with several underlying conditions including diabetes, hyperlipidemia, obesity, metabolic syndrome, insulin resistance. The exact cause of PCOS has not been completed elucidated. There is evidence for several mechanisms including genetic predisposition, a hormonal disorder affecting the hypothalamic pituitary axis, an ovarian disorder and a disease of low grade inflammation. A link between PCOS and autoimmunity has been suggested and continues to be studied.

Autoimmune thyroid disease (AITD) is one of the most common autoimmune diseases in the population and may affect up to 5 % of the population. For this reason, it has been the subject of great research interest among PCOS researchers trying to study the link between PCOS and autoimmune diseases.

A recent large study suggests that women with polycystic ovarian syndrome (PCOS) are at increased risk of developing autoimmune thyroid disease.

Autoimmune Thyroid Disease is Increased in Women with PCOS

A 2018 meta-analysis study set out to examine whether women with PCOS were more likely to have autoimmune thyroid disease than women who did not have PCOS. Romitti and colleagues performed a meta-analysis of 13 studies examining this association. The 13 studies included 1,210 women diagnosed with PCOS. Comparisons were made to 987 healthy controls who did not have PCOS.

The authors found a significant association was detected between PCOS and chance of having autoimmune thyroid disease. In fact, the overall risk of thyroid disease was increased 3.27 times. The authors propose that screening for thyroid function and thyroid antibodies should be considered in all women with PCOS.

Comments

This is an interesting study. This study lends support to the notion that there could be a link between PCOS and thyroid disease. I see many patients with PCOS in my practice. Some diagnoses are easy and some are challenging. The presence of autoimmune thyroid diseases is a factor that tips the balance sometimes in support of making a diagnosis of PCOS in really challenging cases. We know that TSH levels are higher patients with PCOS than controls. Recent studies in PCOS by Cai et al 2019 even suggest that as TSH levels climbs we can expect a greater chance of finding hyperandrogenism in blood tests ( which they defined as a free androgen index above 7).

References

Cai J et al. High Thyroid Stimulating Hormone Level Is Associated With Hyperandrogenism in Euthyroid Polycystic Ovary Syndrome (PCOS) Women, Independent of Age, BMI, and Thyroid Autoimmunity: A Cross-Sectional Analysis.Front Endocrinol (Lausanne). . 2019 Apr 10;10:222

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Romitti M et al. Endocr Connect. 2018 Oct 26;7(11):1158-1167. Association between PCOS and autoimmune thyroid disease: a systematic review and meta-analysis

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