Relationship Between Thyroid Hormones And Metabolic Syndrome In Type 2 Diabetes With Euthyroidism

Background and ObjectiveMetabolic syndrome?MS?is a metabolic disorder syndrome represented by a series of cardiovascular risk factors,including abdominal obesity,hyperglycemia,hypertension,and dyslipidemia.The World Health Organization's Diabetes Advisory Group officially proposed the concept of MS in 1998.There have been many studies on the interaction of thyroid dysfunction in diabetic patients with MS,but there is no unified conclusion on the relationship between MS and type 2 diabetes with euthyroidism.Therefore,our study analyzed the thyroid function and metabolic characteristics of patients with type 2 diabetes in recent years,and explored the correlation of normal thyroid function with MS in them,which will provide a theoretical basis for future research and prevent diabetic patients from developing MS.Object and Method1.204 cases of T2DM patients who met the the following exclusion criteria admitted to the department of endocrinology,First Affiliated Hospital of Zhengzhou University from January 2018 to January 2019 were collected.Those with thyroid diseases,hypothalamic diseases,pituitary diseases,endocrine neoplasia and other system diseases are excluded in this study,as were subjects having taken foods or drugs that affect thyroid function in the past 3 months.In addition,subjects with fever,surgery,trauma,pregnancy and other stressful conditions were also excluded.2.General information including smoking history,drinking history,diabetes history,gender,blood pressure and the age of all subjects were summarized;the height and weight were measured after taking off patient's shoes and dressing in light clothing,and the body mass index?BMI?=weight?Kg?/height?m²?;total cholesterol?TC?,triglyceride?TG?,high-density lipoprotein cholesterol?HDL-C?,and low-density lipoprotein cholesterol?LDL-C?,free triiodothyronine?FT₃?,free thyroxine?FT₄?,thyroid stimulating hormone?TSH?,glycosylated hemoglobin?HbA1c?and other biochemical indicators were measured in the morning after fasting8-10h.all patients underwent oral glucose tolerance test and insulin release test,and the steady-state model was used to calculate the insulin resistance index?HOMA-IR?,insulin?-cell function index?HOMA-??using the formulas respectively,and the Matsuda index was used to assess the insulin sensitivity IS?ISI_M?.3.All patients were grouped according to different gender,MS and thyroid function.?1?basic data were analyzed according to different gender;?2?Patients were divided into two groups according to MS or non-MS,and explored the correlation with DM history,age,sex,smoking history,drinking history,FT₃,FT₄,TSH and MS components;?3?The association of thyroid hormone index?FT₃,FT₄,TSH,FT₃/FT₄?tertiles?T1,T2,T3?with MS components was analysed;?4?Correlation analysis was used to analyze the relationship between TSH,FT₄,FT₃ and MS components;?5?Logistic regression analysis was performed to analyze the risk factors of MS in T2DM patients.4.Statistical methods:The data was statistically analyzed by SPSS 21.0 software.P<0.05 was considered statistically significant.Results1.Analysis of basic data of T2DM patients:the prevalence of MS in T2DM patients was 63.2%,among which the prevalence of males and females were 66.9%and 54.2%,respectively.And there were no significant differences between the two groups?P>0.05?.In addition,compared with the female patients,the BMI,smoking history,drinking history,FT₃,FT₄,TG and DBP were significantly increased in male?P<0.05?;the age,HDL-C,LDL-C level were lower than female?P<0.05?;there were no significant differences between TC,TSH,SBP,HbA1c,HOMA-IR,HOMA-?and ISIM in two gender groups?P>0.05?.2.Analysis of MS group and non-MS group:BMI,TSH,SBP,DBP,TC,TG,HOMA-?,HOMA-IR,HbA1c in MS group were significantly higher than those in non-MS group?P<0.05?;HDL-C and ISI_M were significantly lower than those in non-MS group?P<0.05?.There was no significant differences in FT₄,FT₃,FT₃/FT₄levels,age,gender,smoking history,and diabetes history between the two groups?P>0.05?.3.Patients were divided into three groups?T1,T2,T3?according to the thyroid hormone index?FT₃,FT₄,TSH,FT₃/FT₄?tertiles.Among the three groups of FT₃,the prevalence of MS in group T1,T2 and T3 were 54.9%,68%,and 57.1%,respectively.And there were no significant differences between three groups?P>0.05?.In addition,the DBP and TG levels in group T3 were higher than those in group T1?P<0.05?;the ISIM index in group T1 was higher than that in group T2?P<0.05?;there were no significant differences between BMI,SBP,TC,HDL-C,LDL-C,HbA1c,HOMA-IR and HOMA-?in three groups?P>0.05?.Among the three groups of FT₄,the prevalence of MS in group T1,T2 and T3 were 65.5%,60.0%and 66.7%,respectively.And there were no significant differences between the three groups?P>0.05?.In addition,The SBP in group T2,T3 was higher than that in group T1?P<0.05?.There were no significant differences in BMI,DBP,TC,HDL-C,LDL-C,HbA1c,HOMA-IR,HOMA-?,and ISIM between three groups?P>0.05?.Among the three groups of TSH,the prevalence of MS in group T1,T2 and T3 were 41.3%,86.7%and 95%,respectively.The prevalence of MS in group T2 and T3 was higher than that in group T1?P<0.05?;the BMI and HbA1c in group T2 and T3 were significantly higher than those in group T1?P<0.05?;the SBP and HbA1c in group T3were significantly higher than group T1 and T2?P<0.05?;the TG in group T3 was significantly higher than that in group T1?P<0.05?;there were no significant differences in DBP,TC,HDL-C,LDL-C,HOMA-IR,HOMA-?and ISI_M between three groups?P>0.05?.Among the three groups of FT₃/FT₄,the prevalence of MS in group T1,T2 and T3 were 59.8%,66.1%and 50%,respectively.And there were no significant difference in the prevalence of MS between the three groups?P>0.05?;The DBP in group T2 was significantly higher than that in T1 group?P<0.05?;There were no significant differences in BMI,SBP,TG,TC,HDL-C,LDL-C,HbA1c,HOMA-IR,HOMA-?,and ISIM between three groups?P>0.05?.4.The correlation analysis between FT₃,FT₄,TSH and MS components was as follows:FT₃ level was positively correlated with BMI,TG and DBP?P<0.05?,but not obviously correlated with SBP,HbA1c,HOMA-?,HDL-C,HOMA-IR and ISI_M?P>0.05?;FT₄ level was positively correlated with SBP?P<0.05?,but not obviously correlated with BMI,TG,DBP,HbA1c,HOMA-?,HDL-C,HOMA-IR and ISI_M?P>0.05?;TSH level was positively correlated with BMI,SBP,TG,HbA1c,HOMA-??P<0.05?,but not obviously correlated with DBP,HDL-C,HOMA-IR,ISI_M?P>0.05?;FT₃/FT₄ was positively correlated with DBP?P<0.05?,but not obviously correlated with BMI,TG,SBP,HbA1c,HOMA-?,HDL-C,HOMA-IR,ISI_M?P>0.05?.5.Logistic regression analysis showed that TSH were risk factors for MS in T2DM patients,while the gender,age,diabetes history,drinking history,smoking history,FT₃,FT₄ had no correlation with the occurrence of MS in T2DM patients.Conclusion?1?Thyroid function is closely related to MS,the relative increase in the level of TSH may be related with high SBP,BMI,TG and HbA1c levels in T2DM patients;The relative increase in the level of FT₃ may be related with high DBP,TG in T2DM patients;The relative increase in the level of FT₄ may be related with high SBP in T2DM patients;?2?The relative increase in the level of TSH may increase the incidence of MS in type 2 diabetes with euthyroidism.