The Change Of Serum Proinsulin And The Ratio Of PI/IRI In Patients With Hyperthyroidism And Its Clinical Significance

Objective To observe the change of glucose metabolism and serum PI/IRI,PI/IRI in patients with hyperthyroidism before and after treatment and to study the effect of hyperthyroidism on the function of B cell of pancreas.Methods There are 30 impaired glucose regulation subjects and 30 normal glucose regulation subjects that selected by OGTT in the 162 patients with hyperthyroidism, and 30 type 2 diabetes millitus subjects as well as 30 healthy controls. The levels of serum IRI .PI,FT3,FT4,TSH were determined with RIA in all of these subjects. The levels of fasting glucose and postprandial glucose were drtermined by biochemistry analyzer. After formal antithyroid treatment, these indexes were examined again. The results of PI and IRI were showed by geometric and lnx slnx. The average were analyzed by anova and by q test. Correlative test between two variables were analyzed by beeline correlative analyze. The data were analyzed by paired t test between before and after treatment.Results (1)There were 32 impaired glucose regulation subjects in the 162 patients with hyperthyroidism by OGTT. There are 2 subjects with IFG and 28 subjects with IGT and 2 subjects with IFG and IGT. There is no DM. Incidence is 19. 75%. (2)PI,RI,PI/ IRI was significantly higher in the group with HT+IGR than those in HT + NGR group and higher in both HT+IGR and HT+NGR groups than those in control group. (3)With FT3.FT4 down to normal(98. 77%), PI,IRI,PI/IRI was significantly lower after antithyroid drug treatment. (4)HOMA-IR was significantly higher in both HT+IGR and HT + NGR groups than that in the control group, but lower than that in type 2 diabetes mellitus group. The difference between subgroups with hyperthyroidism was no significance. (5) While FT3,FT4 became normal after treatment, HOMA-IR was significantly lower than that before treatment. (6)The level of PI correlated to BMI, FPG, FT3, FT4. In multiple regression analyses, PI was positively correlated with BMI and FT3.Conclusion Incidence of hyperthyroidism with IGR is 19. 75%, the major type is IGT. Whether IGR exists or not, the level of serum PI, PI/IRI increases in patients withhyperthyroidism, especially in HT+IGR. With FT3, FT4 down to normal after treatment, PI,PI/IRI was significantly lower than before treatment. There exists temporary insulin resistance in patients with hyperthyroidism. It shows that impaired function of pancreas B cells exists in hyperthyroidism, which contributes to stimulating effect on B cells of pancreas by both hyperglucose and thyroid hormone.