Subclinical hypothyroidism: Controversies to consensus

Diagnoses of subclinicaal hypothyroidism (SCH) is biochemically made, when serum thyroid stimulating hormone (TSH) levels is elevated while free thyroid hormone levels are within normal reference range. SCH is diagnosed after excluding all other causes of elevated TSH levels. Symptoms of SCH may vary from being asymptomatic to having mild nonspecific symptoms. The risk of progression to overt hypothyroidism is related to number of factors including initial serum TSH concentration, presence of auto antibodies, family history and presence goiter. Various screening recommendations for thyroid function assessment are in practice. There are still controversies surrounding SCH and associated risk of various cardiovascular diseases (CVDs), pregnancy outcomes, neuropsychiatric issues, metabolic syndrome, and dyslipidemia. Consensus will require more large randomized clinical studies involving various age groups and medical condition, especially in developing countries. All these efforts will definitely improve our understanding of disease and ultimately patient outcomes.