The Battle-field of Subclinical Hypothyroidism

To treat or not to treat subclinical hypothyroidismis a question, which internationallycreates much discussion and writing. Subclinicalhypothyroidism is biochemically detinedby a serum TSH above the upper referencelimit. whereas serum T4 estimates arewithin the reference range. This pattern ofbiochemistry indicates a slightly failing thyroidgland. Both subclinical and overt hypothyroidismshow large differences in epidemiologybetween populations, probablycaused by a combination of environmentaland genetic factors. Whereas there has beenconsensus on the benefits ofthyroid hormonereplacement therapy of overt hypothyroidismfor more than 100 years, opinions on how todeal with subclinical hypothyroidism are farfrom unanimous.