An update on subclinical hypothyroidism and subclinical hyperthyroidism.

Area of Science:

• Endocrinology
• Thyroidology

Background:

• Subclinical thyroid dysfunction presents with normal peripheral thyroid hormone levels and abnormal thyroid-stimulating hormone (TSH).
• Subclinical hypothyroidism and subclinical hyperthyroidism are defined by elevated or suppressed TSH, respectively.
• Management strategies, particularly for subclinical hypothyroidism, remain subjects of ongoing debate.

Purpose of the Study:

• To review and clarify the management of subclinical thyroid dysfunction.
• To provide recommendations for thyroxine therapy in subclinical hypothyroidism.
• To outline treatment considerations for subclinical hyperthyroidism.

Main Methods:

• Review of current literature and clinical guidelines.
• Analysis of TSH levels and associated comorbidities.
• Synthesis of expert consensus on thyroid dysfunction management.

Main Results:

• Selective thyroxine therapy is suggested for TSH levels between the upper limit of normal and 10 mIU/L in subclinical hypothyroidism.
• Treatment is recommended for TSH > 10 mIU/L, aligning with major endocrinology guidelines.
• Treatment for subclinical hyperthyroidism is advised for persistent TSH < 0.1 mIU/L, especially with nodular goiter.

Conclusions:

• Management of subclinical hypothyroidism should be individualized, with thyroxine therapy considered selectively.
• Persistent low TSH in subclinical hyperthyroidism warrants treatment, particularly when comorbidities are present.
• Recommendations align with established guidelines from the American Thyroid Association and American Association of Clinical Endocrinologists.