Evaluation of sub-clinical thyroid disease in adult patients

Sub-clinical or "Mild" thyroid disease is a common disorder, particularly in middle-aged and elderly individuals. Both sub- clinical hypothyroidism and hyperthyroidism are diagnosed, based on laboratory evaluation with mild if any clinical signs or symptoms. Sub-clinical hypothyroidism is defined as an elevation in serum TSH above upper limit of the reference range with normal serum Free T4 concentration; sub-clinical hyperthyroidism is defined as a decrease in serum TSH below the reference range with normal serum Free T3 and T3 concentration. It is reported that most patients who found to have sub-clinical thyroid disease have TSH values between 4.5 and 10 �IU/L (reference range 0.45�IU/L - 4.5�IU/L). We present here studies carried out during Dec 2002-Dec 2006 in 202 patients (80 males, 122 females) regarding evaluation of sub-clinical thyroid disease. Their TSH, T3 T4, FT3 and FT4 levels were also determined and data is cumulated and presented as percent occurrence. In female groups of 122 patients, 21 (17.21%) exhibited sub-clinical thyroid disorders (n=13; 10.65% Sub-clinical hypothyroidism, n=8; 6.55% sub-clinical hyperthyroidism), whereas 43 (35.24%) exhibited true- thyroid disorder. In male group of 80 patients; 9 patients (11.25%) showed sub-clinical thyroid disorders (n=8; 10% sub-clinical hypothyroidism; n=1; 1.2% sub-clinical hyperthyroidism), whereas 18 (22.5%) exhibited true thyroid disorder. It is concluded that sub- clinical thyroid dysfunction predicts future progression to overt disease. It is also advisable that routine screening for thyroid disease through clinical investigations aided with lab findings be promoted, especially in pregnant women.