What is Hashimoto's thyroiditis (Autoimmune thyroiditis)?

From the Guidelines

Hashimoto thyroiditis should be treated with oral T4 monotherapy (levothyroxine sodium) as the principal treatment for hypothyroidism, with the goal of improving morbidity, mortality, and quality of life. The treatment approach for Hashimoto thyroiditis involves managing the resulting hypothyroidism, which is typically achieved through daily oral levothyroxine administration [ 1 ]. The dosage of levothyroxine is usually initiated at 1.6 mcg/kg body weight and adjusted based on thyroid function tests, specifically thyroid-stimulating hormone (TSH) levels, every 6-8 weeks until stable, and then annually [ 1 ]. Key considerations in the management of Hashimoto thyroiditis include:

• Regular monitoring of TSH levels to maintain proper dosing of levothyroxine
• Awareness of the increased risk for other autoimmune conditions
• Potential benefits of selenium supplementation (200 mcg daily) in reducing antibody levels, although evidence is mixed [ 1 ]
• The importance of treating hypothyroidism to improve cardiovascular- and cancer-related morbidity and mortality, as well as falls, fractures, functional status, and quality of life [ 1 ]. It is essential to note that while levothyroxine treats the hypothyroidism resulting from Hashimoto thyroiditis, it does not stop the autoimmune process [ 1 ]. Therefore, patients may require lifelong medication and should be monitored regularly for any changes in their condition or the development of other autoimmune diseases.

From the FDA Drug Label

As replacement or supplemental therapy in patients with hypothyroidism of any etiology, except transient hypothyroidism during the recovery phase of subacute thyroiditis This category includes cretinism, myxedema and ordinary hypothyroidism in patients of any age (pediatric patients, adults, the elderly), or state (including pregnancy); primary hypothyroidism resulting from functional deficiency, primary atrophy, partial or total absence of thyroid gland, or the effects of surgery, radiation, or drugs, with or without the presence of goiter; and secondary (pituitary) or tertiary (hypothalamic) hypothyroidism As pituitary thyroid-stimulating hormone (TSH) suppressants, in the treatment or prevention of various types of euthyroid goiters, including thyroid nodules, subacute or chronic lymphocytic thyroiditis (Hashimoto's) and multinodular goiter

Hashimoto thyroiditis is a condition that can be treated with liothyronine (PO) as a TSH suppressant. The drug can be used in the treatment or prevention of euthyroid goiters, including thyroid nodules, subacute or chronic lymphocytic thyroiditis (Hashimoto's), and multinodular goiter 2.

From the Research

Definition and Prevalence of Hashimoto Thyroiditis

• Hashimoto thyroiditis is one of the most common organ-specific autoimmune diseases and the most frequent cause of hypothyroidism in areas with sufficient iodine supply 3.
• It affects women 7-10 times more often than men 4.
• Clinical hypothyroidism affects one in 300 people in the United States, with a higher prevalence among female and older patients 5.

Pathogenesis and Risk Factors

• Excessively stimulated T cells CD4+ and their differentiated cells play a key role in the pathogenesis of Hashimoto thyroiditis 3.
• Genetic susceptibility, environmental factors, existential factors (gender difference), and gut and intestinal microbiota contribute to its development 3, 4.
• The presence of thyroid peroxidase antibodies (TPOAbs) is associated with a 2 to 4-fold increase in the risk of recurrent miscarriages and preterm birth in pregnant women 4.

Diagnosis and Treatment

• Diagnosis requires a detailed medical history, sonography, and blood analysis of thyroid function and thyroid antibodies 3.
• Levothyroxine replacement therapy is the standard treatment for hypothyroidism, with a starting dose of 1.5 to 1.8 mcg per kg per day 5, 4.
• Patients with persistent symptoms after adequate levothyroxine dosing should be reassessed for other causes or the need for referral 5.
• There is no evidence to recommend combination therapy with levothyroxine and liothyronine for most patients with hypothyroidism 5, 6.

Cognitive Functioning and Quality of Life

• Patients with Hashimoto thyroiditis on long-term levothyroxine replacement may experience persistent impairments in cognitive functioning and general well-being 7.
• Global cognitive function, conceptual tracking, verbal divergent thinking, and anxiety and depression scores are significantly worse in patients with Hashimoto thyroiditis compared to controls 7.
• Quality of life is impaired in patients with Hashimoto thyroiditis, with a significant negative correlation between antibodies (TPOAb, TgAb) and quality of life 7.