MON-377 Understating the correlation between Postural Orthostatic Tachycardia Syndrome (POTS) and Hashimoto’s Thyroiditis

Abstract Disclosure: V. Suarez: None. C. Naranjo: None. M.J. Barroso Alverde: None. A. Mizrahi Drijanski: None. I. Noemi Torres: None. A. Aguilar Rico: None. L. Padrón Alcántara: None. Postural Orthostatic Tachycardia Syndrome (POTS), a chronic autonomic disorder, marked by excessive tachycardia upon orthostasis, presents with dizziness, fatigue, and palpitations. Its exact cause is unclear, but evidence suggests a strong autoimmune association, as many patients present with autoimmune markers. Hashimoto’s Thyroiditis, an autoimmune disease destroying thyroid cells, leads to thyroid hormone fluctuations affecting autonomic regulation, cardiovascular function, and inflammation. Pro-inflammatory cytokines in both conditions support immune dysregulation in autonomic instability. Hashimoto’s is a common autoimmune comorbidity in POTS, suggesting a link between thyroid autoimmunity and autonomic dysfunction.Understanding how immune-mediated thyroid dysfunction impacts POTS may improve diagnosis and treatment strategies. The aim of this review is to evaluate the correlation between POTS and Hashimoto's Thyroiditis by investigating immune mechanisms linking both conditions. Studies support an autoimmune component in POTS, identifying autoantibodies targeting adrenergic and muscarinic receptors. Autoimmune dysregulation, particularly adrenergic receptor autoantibodies, contribute to excessive sympathetic activation. Studies suggest that one in seven POTS patients tested positive for ganglionic acetylcholine receptor antibodies, proving an autoimmune etiology.Direct studies linking POTS and Hashimoto’s are limited, but thyroid dysfunction is prevalent in POTS patients. Autoimmune thyroid disease is commonly observed in autonomic disorders, suggesting shared immunological mechanisms. POTS frequently coexists with other autoimmune diseases, strengthening the immune-mediated autonomic dysfunction hypothesis.Thyroid hormone fluctuations may influence autonomic function, as T3 and T4 regulate cardiovascular homeostasis. Hypothyroidism in Hashimoto’s may worsen autonomic instability; it affects baroreceptor sensitivity, catecholamine release, and vascular tone.Findings suggest a strong connection between autoimmunity and autonomic dysfunction in POTS, with thyroid dysfunction playing a role. Research is needed to clarify the mechanisms linking thyroid autoimmunity and autonomic dysregulation in POTS patients. Given the high prevalence of autoimmune comorbidities in POTS patients, further research is crucial to understand the role of thyroid dysfunction in POTS pathophysiology. A deeper understanding of these mechanisms will enhance diagnostics, management, and treatment approaches for affected individuals. Presentation: Monday, July 14, 2025