SUN-413 Thyroid Stimulating Hormone Levels Amongst Reproductive Age Latinas: Findings from the ELLAS Study

Abstract

BACKGROUND: National population data on thyroid disease in women comes largely from NHANES. Prior research utilizing data from NHANES 1999-2002 indicated a 3.1% prevalence of hypothyroidism and 0.6% prevalence of hyperthyroidism among reproductive aged women. In this dataset, Mexican Americans had a similar risk of hypothyroidism but a slightly higher rate of hyperthyroidism when compared to non-Hispanic whites. We present data from a prospective cohort study of reproductive aged Hispanic women residing in the United States (US) in order to examine thyroid disease prevalence in this population.Methods: The Environment, Leiomyomas, Latinas and Adiposity Study (ELLAS) is a prospective NIMHD funded longitudinal cohort study of reproductive age Latinas/Latinx females in Southeast Michigan. Demographic and health data were collected via bilingual interviewers. Height, weight, and body composition were measured by trained staff using a Tanita MC780U scale. Fasting morning venipuncture was performed and samples were collected in a serum separating tube and sent to a commercial lab (Labcorp – Burlington, NC) for TSH electrochemiluminescence immunoassay [normal reference range 0.45-4.5 mIU/L]. The data were analyzed using SAS version 9.4 (Cary, NC).Results: 516 patients have enrolled in ELLAS and 450 of these have completed the first study visit. Mean age, BMI, and body fat % were 37.7 ± 7.0 years, 29.9 ± 6.8 kg/m2, 36.3% ± 6.6% (mean ± SD) respectively. Reported countries of birth were Mexico (76.2%), US (9.8%), Central America (6.7%), South America (5.6%), and the Caribbean Islands (0.7%). 34 (7.6%) participants reported a pre-existing thyroid condition. Of those, 28 reported they had been treated for a thyroid condition in the past, and 14 were currently taking prescription medication for thyroid disease. TSH levels were available on 418 women. Of those with a known thyroid condition, 6.5% had TSH values < 0.45 and 16.1% had elevated TSH values (> 4.5) at the time of their study visit, compared to 1.7% and 7.4% overall. 0.2% had TSH > 10. Among those without a known history of thyroid disease, 1.3% had TSH < 0.45 and 6.7% had TSH > 4.5 at their visit. BMI, body fat %, and country of birth were not associated with TSH levels, but there was a small yet significant effect of age on TSH (p=0.009).Conclusion: In this US cohort of Hispanic women of reproductive age, we observed a high prevalence of thyroid dysfunction in those without pre-existing disease. In women with a known thyroid condition, the prevalence of abnormal TSH values was also high, representing both under- and over-treatment with thyroid hormone. Screening for thyroid disease in this population is important and presents a potential opportunity for intervention in an often underserved population.