SAT0611 PREVALENCE OF HYPOTHYROIDISM WITH THERAPEUTIC INDICATION IN PATIENTS WITH RHEUMATOLOGICAL DISEASES
Authors: Sho Fukui, Yukihiko Ikeda, Haruki Sawada, Mitsuru Watanabe, Ayako Koido, Rui Imai, Masei Suda, Haruyuki Yanaoka, Hisanori Shimizu, Ryo Rokutanda, Hiromichi Tamaki, Tokutarou Tsuda, Kenichi Yamaguchi, Mitsumasa Kishimoto, Masato Okada
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Hypothyroidism is known as a common complication of rheumatological diseases(RD). Thyroid hormone supplementation is important not only in clinical hypothyroidism but subclinical one for cardiovascular events in the future<sup>1</sup>. But the data about prevalence of hypothyroidism requiring treatment and it's changes with follow up in patients with RD is limited. <h3>Objectives</h3> To reveal the prevalence and risk factors of hypothyroidism, especially which requires thyroid hormone supplementation, in patients with RD and compare it with that of general population. <h3>Methods</h3> We retrospectively reviewed charts of RD patients and healthy controls in preventive medicine center, at St. Luke's International Hospital from January 2004 to July 2018. We investigated basic demographics, underlying diseases, blood tests including thyroid functions and treatment with thyroid hormones. We compared the number of hypothyroidism requiring treatment (Thyroid stimulating hormone: TSH 10 μU/mL or physician started treatment) and it's changes in follow up using univariate analysis and Kaplan–Meier method with log rank test. Cox proportional hazard model was performed for evaluating the risk of hypothyroidism which needs treatments in all patient and only RD patients. <h3>Results</h3> 2307 RD patients and 78251 controls without past medical history of hypotyroidism with therapeutic indications are included. Newly-detected hypothyroidisms requiring treatments are significantly frequent in RD patients (6.9%vs2.0%, P&lt;0.001) (table.1). Kaplan–Meier method and Cox's proportional hazards model revealed having RD and high baseline TSH ( 4.5 μU/mL) are strongly associated with hypothyroidism requiring treatments (adjusted hazard ratio: HR = 4.39; 95%CI 3.35-5.75, and 25.9; 95%CI 23.4-28.6, respectively) (Figure 1). When focus on RD patients, patients with older age, ANA (Anti-nuclear antibody)80, higher Cre and TSH, and baseline positive anti-thyroid peloxydase(TPO-Ab) or anti-thyrogloburin antibodies(Tg-Ab) have higher risk of hypothyroidism requiring treatment after adjusting confounders in Cox's proportional hazards model (Table.2). <h3>Conclusion</h3> Hypothyroidism with therapeutic indication is more frequent in RD patients, even if screening TSH is within normal range. We encourage active routine measurement of thyroid function tests in patients with RD, especially with above risk factors. <h3>References</h3> [1] Nicolas Rodondi, et al. Subclinical Hypothyroidism and the Risk of Coronary Heart Disease and Mortality: JAMA. 2010;304(12):1365-1374. <h3>Disclosure of Interests</h3> Sho Fukui: None declared, Yukihiko Ikeda: None declared, Haruki Sawada: None declared, Mitsuru Watanabe: None declared, Ayako Koido: None declared, Rui Imai: None declared, Masei Suda: None declared, Haruyuki Yanaoka: None declared, Hisanori Shimizu: None declared, Ryo Rokutanda: None declared, Hiromichi Tamaki: None declared, Tokutarou Tsuda: None declared, Kenichi Yamaguchi: None declared, Mitsumasa Kishimoto Consultant for: Kyowa Hakko Kirin Co., Ltd., Masato Okada: None declared