Different levels of thyroid hormones between impaired fasting glucose and impaired glucose tolerance: free T3 affects the prevalence of impaired fasting glucose and impaired glucose tolerance in opposite ways.

CONTEXT: There is an association between thyroid disorders and diabetes mellitus. OBJECTIVE: To investigate thyroid hormone levels in different glucose metabolic statuses, analyse relationships between thyroid hormone levels and different categories of prediabetes and metabolic parameters within a large euthyroid nondiabetic population. METHODS: A total of 3328 subjects without diabetes or thyroid dysfunction were included in this cross-sectional study. Subjects were divided in to four groups [normal glucose tolerance (NGR), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and combined glucose intolerance (CGI)] according to the results of oral glucose tolerance test. Participants were then divided into four groups according to the quartile of free T3 (FT3) in their blood. RESULTS: Subjects with IFG had higher levels of FT3 and ratio of FT3 to FT4 (FT3/FT4), but lower level of free T4 (FT4) than subjects with IGT. FT3/FT4 was negatively associated with postprandial plasma glucose (PPG) [standardized ß (ß) = -0·087; P < 0·001]. The prevalence of IFG and CGI was increased with the level of FT3, while the prevalence of IGT was decreased with the level of FT3 (P for trend: <0·001, 0·003 and <0·001, respectively). FT3 was negatively associated with the risk of IGT (OR = 0·409, 95% CI 0·179-0·935), whereas FT4 was positively associated with the risk of IGT (OR = 1·296, 95% CI 1·004-1·673). CONCLUSIONS: Free thyroid hormone levels were different between subjects with IFG and IGT. FT3 affects the prevalence of IFG and IGT in opposite ways. The difference in thyroid hormone levels may play an important role in the different pathological mechanisms of IFG and IGT.

Investigation on peripheral blood TSHR mRNA for differentiation of benign and malignant thyroid nodules / 中华内分泌代谢杂志

Objective To assess the value of peripheral blood thyroid stimulating hormone receptor(TSHR) mRNA determination in differential diagnosis of benign and malignant thyroid nodules.Methods Fine needle aspiration cytology (FNAC) and (or) postoperative histopathology as the gold standard were carried out,the expression of circulating TSHR mRNA was determined by RT-PCR in 33 patients with benign thyroid nodules,39 patients with thyroid cancer,and 20 normal controls.Results TSHR mRNA signals were not detected in normal controls,the positive rate of TSHR mRNA was higher in the group with malignant nodules than the group of benign nodules (91.2％ vs 48.5％,P＜0.01).TSHR mRNA level in the preoperative malignant group was significantly higher than that in the normal,benign,and postoperative cancer groups (all P ＜ 0.01).Using peripheral blood TSHR mRNA for differentiating benign or malignant of thyroid nodule had a sensitivity,specificity,and accuracy of 91.2％,51.5％ and 71.6％,respectively.The sensitivities of TSHR mRNA,FNAC,and these two methods combined in detecting malignant nodules were 91.3％,86.9％,and 100.0％ respectively,while diagnostic accuracies were respectively 84.0％,80.0％,and 92.0％.TSHR mRNA expression showed no significant relationship with sex,age,size,and number of nodule in these patients (all P ＞ 0.05),but it did exhibit significant difference between benign and malignant nodules(P＜0.01).Conclusion The peripheral blood TSHR mRNA could be used as a molecular marker for thyroid cancer,and it would help enhance the preoperative differentiation of benign and malignant thyroid nodules.

Risk factors analysis of microalbuminuria in patients newly diagnosed with type 2 diabetes mellitus / 中国综合临床

Objective To analyze the incidence and risk factors of microalbuminuria in newly diagnosed and hospitalized type 2 diabetes mellitus patients,and to provide the theoretical basis for therapy of diabetes and diabetic chronic complications.Methods The blood glucose,lipid profile,24h-urinaryalbumin,fasting and postprandial serum insulin and peptid C were measured in 286 newly diagnosed and hospitalized type 2 diabetic patients from Mar.2006 to Sep.2009.Microalbuminuria was defined as the 24h-urinary albumin between 30 to 300 mg twice.Insulin resistance index (HOMA-IR) was recorded and all the patients received fundus examination by ophthalmologists after expansion of the pupil to ensure whether there was retinopathy or not.Results (1)The incidence rate of microalbuminuria in this study was 19.58％ (56/286).(2)Normal albuminuria group and MA group combined DR were 19.57％ (45/230) and 33.93 ％ ( 19/56 ) respectively,and the difference was statistically significant( x2 =5.349,P =0.021 ).Compared with control,the FPG,HbA1c and HOMA-IR were significantly higher in microalbuminuria group ( FPG:[ 11.08 ± 1.76 ] mmol/L vs [9.24 ±1.65]mmol/L,t =-6.148,P ＜0.001;HbA1c:[11.54 ± 1.59]％ vs [9.39 ± 1.64]％,t =-7.533,P ＜0.001 ;HOMA-IR:[3.73 ±0.42] vs [3.50 ±0.30],t =-3.774,P ＜0.001 ).(3) Pearson correlation analysis revealed microalbuminuria was positively correlated with FPG( r =0.460),HbA1 c ( r =0.499),HOMA-IR( r =0.308)and combined DR(r =0.405)(P ＜0.01).(4)Stepwise multiple regression analysis revealed that FPG (ββ =- 0.804,P ＜ 0.01 ),HbA1 c (β =- 0.455,P ＜ 0.01 ) and combined DR (β =1.527,P ＜ 0.05 ) were independently risk factors of microalbuminuria.Conclusion The development of microalbuminuria in newly diagnosed and hospitalized type 2 diabetic patients is associated with FPG,HbA1c and HOMA-IR,and will be easier to merge diabetic retinopathy.