The effects of treatment of subclinical hypothyroidism on metabolic control and hyperinsulinemia.
We examined the effects of treatment of subclinical hypothyroidism (SH) on metabolic control and hyperinsulinemia. The study included 53 patients ages 53.42+/-3.11 years, BMI = 28.43+/-1.67 kg/m2, with SH. Laboratory evaluation included serum free T3, free T4, TSH, thyroid antibodies, TGL, insulin, C-peptide and glucose during OGTT, HbA1c, CRP and level of lipids. Twelve SH patients (37.7 %) had diabetes mellitus (DM), 14 patients (26.4 %) had glucose intolerance (GI) and 35 patients were obese (66 %). All patients were treated with L-thyroxin (25-50 microg). Patients with DM and GI were treated with diabetic diet, physical activity and previously antidiabetics without change of doses. After the six months of treatment, patients had normal or limited TSH (8.43+/-2.14 vs. 4.22+/-1.23 ulU/ml), level of fasting insulin (176+/-42 vs. 119+/-30 pmol/l) significantly decreased, level of HbA1c (7.2+/-1.3 vs. 5.8+/-0.6 %) decreased as well. The level of fasting and postprandial glucose significantly decreased, level of CRP decreased as well. The level of total cholesterol, as well as triglycerides, HDL and LDL cholesterol were changed. The correlation between TSH and HbA1c was positive and significant. These data support an important role of treatment of SH in support metabolic control and insulin sensitivity.