Should we treat mild subclinical/mild hyperthyroidism? No.
Authors: Vanderpump MP
The management of a patient with subclinical hyperthyroidism or mild thyroid over-activity is controversial. Subclinical hyperthyroidism is defined as a serum thyrotrophin (TSH) below the reference range but a normal thyroxine (T(4)) and triiodothyronine (T(3)) level in a patient who is either asymptomatic or has only non-specific symptoms. Epidemiological studies report an overall prevalence of approximately 3%, with men and women over 65years and those in iodine deficient regions having the highest prevalence. Approximately 50% of subjects are taking levothyroxine. The aetiology for those with endogenous subclinical hyperthyroidism is Graves' disease, toxic nodular goitre or rarely a solitary toxic adenoma or thyroiditis. Non-thyroidal illness is an important c...
Benefit of Combined Triiodothyronine (LT3) and Thyroxine (LT4) Treatment in Athyreotic Patients Unresponsive to LT4 Alone
The objective of this paper is to study a benefit of additional LT3 in athyreotic patients who failed to normalize TSH on LT4 alone even with hyperthyroid serum T4 values.In a survey of 200 athyreotic patients treated between 2006 and 2009, about 7% failed to normalize serum TSH levels following treatment with LT4, though serum T4 values in the hyperthyroid range were achieved. These patients (characterized by serum T4≥160 nmol/L and TSH≥5.0 mIU/L), were additionally treated with 10 μg b. i. d LT3. LT3 and LT4 combination therapy resulted in decreased serum TSH levels into the normal range (12.8 vs. 1.22 mIU/L; plt;0.01) and reduced LT4 dose (153.3 vs. 117.5 μg; plt;0.01) required for normalization of serum T4 values (170.6 vs. 123.3 nmol/L; plt;0.01). Serum T3 val...
