Abstract: Objective To investigate glucose metabolism in type 2 diabetics with subclinical hypothyroidism(SCH).Methods The study population consisted of 1170 cases of type 2 diabetics registered in Beijing Tongren Hospital,and the clinical biochemistry indexes,the functions of thyroid and pancreas islets were examined in the SCH patients and non-SCH type 2 diabetic patients.Results In SCH group,the levels of FBG,PBG,HbA1c and FT₄ were significantly lower,and the levels of TSH,TGA,TPoAb were significantly higher than non-SCH group.In SCH group which TSH>10 mIU/L,the levels of BMI were significantly higher than that of 10≥TSH>4 mIU/L.The C-peptide released test showed that the C-peptide levels of underlying and 3 h after intake 100 g carbohydrate were significantly higher in SCHgroup.But there were no difference in the two SCHsubgroups based on different TSHlevel.The results of correlation analysis showed that in all objects there were significant positive correlation between Cp₀,Cp₁,Cp₂,Cp₃ and TSH,and there were negative correlation between FBG,PBG,HbA1c and TSH.In SCHgroup,there were no significant positive correlation between FBG,PBG,HbA1c,Cp₀,Cp₁,Cp₂,Cp₃ and TSH.Conclusion SCH can affect glucose metabolism,and became notable with the aggravation of SCH.

Key words: subclinical hypothyroidism, type 2 diabetes mellitus, glycometabolism