Current trends in the management of subclinical hypothyroidism: clinical experience and prospects for nutraceutical therapy

Subclinical hypothyroidism (SH) is defined as an elevated thyroid-stimulating hormone (TSH) level with normal free thyroxine (fT4) concentrations within the reference range. It is a common condition, particularly in older adults (more frequently in women), and remains a subject of debate regarding the necessity and benefits of levothyroxine replacement therapy. Aim: to summarize current evidence on the epidemiology, pathophysiology, and associated risks (cardiovascular, metabolic, reproductive), results of randomized clinical trials, and current management recommendations for patients with SH, as well as to present findings from an observational study on the effects of supplementation with ashwagandha, selenium, and iodine on TSH levels in patients with SH. Objective: subclinical hypothyroidism and contemporary perspectives on its diagnosis and treatment. Methods: literature review and results of own observational clinical study. Results. In younger patients, levothyroxine therapy may improve lipid profiles, reduce cardiovascular risk in selected groups, and enhance fertility. In older adults, large randomized trials have not demonstrated significant improvements in quality of life or cognitive function with levothyroxine therapy; thus, treatment should be individualized. Since standard levothyroxine replacement therapy offers benefits only in certain subgroups of patients with SH, specific nutraceuticals may be useful in supporting overall thyroid and metabolic health in this subpopulation. Conclusions. SH is a heterogeneous and often asymptomatic condition. Current data indicate that SH may be either transient or persistent, and the risk of progression to overt hypothyroidism is largely determined by the presence of thyroid peroxidase antibodies (TPOAb), TSH levels >10 mIU/L, and female sex. The clinical significance of SH remains a topic of ongoing debate. Levothyroxine therapy is indicated for younger patients with hypothyroid symptoms, women of reproductive age (especially with positive TPOAb), dyslipidemia, and/or infertility; as well as for pregnant women or those planning pregnancy (for whom treatment indications are more clearly defined). In the presented clinical observation, the addition of the Tyrovit dietary supplement complex (ashwagandha, selenium, iodine) for 3 months contributed to the restoration of euthyroidism and improvement of general well-being in 55% of patients with SH, which is consistent with previous publications.

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