Subclinical hypothyroidism and cardiovascular diseases: Pathogenetic mechanisms and clinical implications

Subclinical hypothyroidism (SH) is a condition characterized by an elevated level of thyroid-stimulating hormone (TSH) with normal concentrations of free thyroxine. In recent years, its impact on the cardiovascular system has been actively discussed, as even a moderate deficiency of thyroid hormones may contribute to the development of dyslipidemia, arterial hypertension, and atherosclerosis. This article analyzes current data on the pathophysiological mechanisms linking SH to cardiovascular diseases and reviews key aspects of diagnosis and therapy for this condition. It has been shown that SH is associated with alterations in lipid profiles, including increased levels of total cholesterol and low-density lipoproteins, which contribute to the progression of atherosclerosis. SH may also lead to endothelial dysfunction and structural and functional changes in the myocardium, increasing the risk of cardiovascular events. Treatment with levothyroxine (L-T₄) improves lipid profiles and vascular function; however, its effect on cardiovascular outcomes remains a subject of debate. Given the potential cardiovascular risks, patients with SH require an individualized approach to diagnosis and treatment. L-T₄ replacement therapy may be appropriate in cases where TSH levels exceed 10 mIU/L or when cardiovascular risk factors are present. Currently, there are many different L-thyroxine medications available on the pharmaceutical market; however, L-thyroxine Berlin-Chemie has a number of key advantages. One of the important distinctions of this medication is the absence of lactose in its composition, making it an optimal choice for patients with lactose intolerance. This medication combines the absence of lactose, high stability, convenience of storage, and reliable protection against external factors, making it an ideal choice for long-term therapy of hypothyroidism. Further clinical research is needed to determine the optimal management strategy.

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