Study On The Relationship Between FT3?FT4 And TSH And Vai In Normal Thyroid Function

Objective: To study the relationship between three factors including serum free triiodothyronine acid,serum free thyroxine,thyroid stimulating hormone,with visceral adiposity index in Dalian community residents with normal thyroid function.Methods: Based on the REACTION study initiated by the Chinese medical association,age,gender,previous disease history,surgery history,medication history,drinking and smoking history were obtained by questionnaire survey;Measuring the height,weight,waist circumference,hip circumference,systolic blood pressure,diastolic blood pressure and heart rate.To calculate body mass index,waist hip ratio?mean systolic blood pressure,mean diastolic blood pressure,mean heart rate.Testing fasting plasma glucose,2 hours plasma glucose,glycosylated hemoglobin,fasting insulin,total cholesterol,high density lipoprotein cholesterol,low density lipoprotein cholesterol,triglycerides,blood uric acid,free triiodothyronine,free thyroxine,thyrotropin,thyroid peroxidase antibody,thyroid globulin antibody,alanine aminotransferase,aspartate transaminase,gamma glutamyl transpeptidase.Calculating the insulin resistance index.Three years later,the follow-up data of the above subjects were retrospectively collected,the indexes were measured at the same baseline,and VAI was calculated.After eliminating those who met the exclusion criteria and those who did not come for follow up,3273 subjects were enrolled in the study.According to the quartile level of FT3,FT4 and TSH,the enrolled population was divided into four groups: Q1,Q2,Q3 and Q4,four groups: Q1,Q2,Q3 and Q4,and four groups: T1,T2,T3 and T4.Further analysis was made on whether FT3,FT4 and TSH were related factors affecting VAI values.Results:1.There was no statistically significant difference in VAI values after three years between FT3 quartile arrays(P>0.05).The median VAI values of each group were 1.98(1.29-3.07),2.01(1.35-3.21),2.04(1.31-3.19),and 2.01(1.27-3.05),respectively.There was a statistically significant difference in VAI values after three years between FT4 quartiles arrays(P<0.05),the median VAI values of each group were 2.14(1.33-3.31),2.03(1.31-3.16),2.01(1.35-3.10)and 1.90(1.21-2.95),after comparisons between each two group,we found that the q1 and q4 group,q2 and q4 group were differences(P<0.05),while q1 and q2 group,q1 and q3 group,q2 and q3 group,q3 and q4 group had no statistical difference(P>0.05).There was a statistically significant difference in VAI after three years between TSH quartiles arrays(P<0.05),the median VAI values of each group were 1.89(1.24-3.00),1.90(1.21-2.87),2.08(1.33-3.30)and 2.17(1.40-3.36),after comparisons between each two group,we found that T1 and T3 group,T1 and T4 group,T2 and T3 group,T2 and T4 group were differences(P<0.05),while T1 and T2,T3 and T4 group were no statistical difference(P>0.05).2.Spearman correlation analysis showed that mean systolic blood pressure,mean diastolic blood pressure,mean heart rate,BMI,waist-to-hip ratio,LDL-C,TC,FPG,2h PG,Hb A1 c,FINS,HOMA-IR,uric acid,TSH,ALT,AST and GGT were all positively correlated with VAI after three years,FT4 was negatively correlated with VAI after three years,while age and FT3 were not correlated with VAI after three years.3.Ln VAI after three years as dependent variable,MSBP,MDBP,WHR,TC,HOMA-IR,Hb A1 c,FT4,TSH,UA in baseline as independent variable,using multiple linear stepwise regression method to establish model,the result showed that UA,WHR,Hb A1 c,HOMA-IR,MDBP,TC,TSH and Ln VAI were positively correlated(P<0.05),FT4 and Ln VAI was negatively correlated(P<0.05),MSBP and Ln VAI has no relevance.(?=0.009,P>0.05).Conclusions: In Dalian community residents with normal thyroid function,the increase of FT4 and the decrease of TSH level can lead to the decrease of VAI value.