Characterization of Thyroid Disease Prevalence Among Transgender and Gender-Diverse Patients

Objective: Transgender and gender-diverse individuals are at risk of insufficient treatment of endocrine diseases due to a number of barriers to care. There are currently no data evaluating the prevalence of thyroid disease in this population, and it is unknown if gender-affirming hormone therapy affects treatment of thyroid disease in these individuals. Methods: Utilizing a registry of 676 patients over 18 years of age who were seen in our Transgender and Intersex Specialty Care Clinic from 2015-2019, we identified 554 individuals seeking medical therapy for gender dysphoria/incongruence. Of these, 56 patients were taking thyroid hormone or antithyroid medications or had a coded diagnosis of thyroid disease; 2 were excluded as they were receiving thyroid hormone as adjunctive therapy for refractory depression. 54 patients were therefore analyzed with respect to thyroid disease (TD+), and compared to those 498 patients without thyroid disease (TD-) with regard to average vital signs, demographics, and presence of common comorbidities. Results: Fifty percent of our TD+ patients were recorded female sex at birth, and 98% were Caucasian. TD+ patients were much more likely to have essential hypertension (OR 5.99), to use tobacco (OR 2.23), and to be overweight or obese (OR 2.16) than TD- patients. Due to the evolving natural history of disease, some TD+ patients belonged to multiple categories: 48 patients, 26 trans feminine and 21 trans masculine, had hypothyroidism, of whom 41 had overt hypothyroidism and 2 patients had subacute thyroiditis that progressed to the hypothyroid phase of illness. 5 patients (3 trans masculine and 2 trans feminine) demonstrated hyperthyroidism, 4 of whom had Graves’ Disease. 2 patients had multinodular goiter, both trans masculine. 2 patients had thyroid malignancies, both trans feminine, of whom one had proven follicular thyroid carcinoma and the other had unspecified thyroid malignancy. Among hypothyroid patients, there was a slight non-significant trend toward increased thyroid hormone requirements while receiving treatment with estradiol or testosterone. Conclusion: To our knowledge, this represents the first attempt to characterize the prevalence of various thyroid disease states in the gender diverse population. Our data corresponded to a prevalence of hypothyroidism of approximately 8.7%, which is higher than previously published estimates of 3-5% in the general population. Whether this represents actual increased prevalence or assessment bias is uncertain. It is important for all health professionals who care for gender diverse people to identify and appropriately treat thyroid disease, and to monitor thyroid function closely if gender-affirming hormone therapy is initiated.