Relationship Between TyG,TG/HDL-C And The Incidence Of Type 2 Diabetes Mellitus

Objective: To investigate the correlation between Ty G and TG/HDL-C and the incidence of type 2 diabetes mellitus（T2DM）in middle-aged and elderly people.Methods: Using the baseline data of "REACTION" study in Lanzhou,collected by an epidemiological survey of permanent residents aged 40～75 years in Lanzhou in2011.According to the inclusion and exclusion criteria,individuals without diabetes were selected and followed up for 3 years without intervention.Excluding those with incomplete follow-up data,3825 subjects were included for analysis.Ty G and TG/HDL-C were grouped according to quartile spacing（first group,second group,third group,forth group）to describe the basic characteristics of the population and assess differences in the incidence of type 2 diabetes mellitus after follow-up.The correlation between Ty G,TG/HDL-C and fasting plasma glucose（FPG）,two hour postload glucose（2h-PG）and glycated haemoglobin（Hb A1c）at follow-up was analysed by Spearman correlation analysis.The relationship between Ty G,TG/HDL-C and the risk of T2 DM was estimated by logistic regression analysis.Receiver operating characteristic（ROC）curve（AUC）analysis was used to compare the predictive value and cut-off points for Ty G,TG/HDL-C.Results（1）A total of 3825 individuals were included,including 954 men and 2871 women,aged 40～75 years old,average（56.84±7.72）years old.Compared to the lowest quartile of Ty G and TG/HDL-C at baseline,the highest quartile showed varying degrees of increase in systolic blood pressure,diastolic blood pressure,FPG,2h-PG,Hb A1 c and triglyceride（TG）,total cholesterol（TC）,low density lipoprotein cholesterol（LDL-C）,while high density lipoprotein cholesterol（HDL-C）showed a decreasing trend（P< 0.05）.（2）After a mean follow-up of 3 years,the cumulative incidence of T2 DM was6.5%,7.4% in men,6.1% in women,2.3% in normal glucose tolerance（NGT）group and 13.7% in impaired glucose regulation（IGR）group.The incidence of T2 DM showed an increasing trend in four groups according to the quartiles of Ty G and TG/HDL-C,with the highest incidence in the Q4 group.In the total population,in men,in women,in NGT group and in IGR group,the cumulative incidence in the highest quartile of Ty G was 11.4%,12.6%,10.9%,6.2% and 15.8%,respectively.The cumulative incidence in the highest quartile of TG/HDL-C was 11.4%,12.4%,10.9%,5.6% and 17.8%,respectively.（P< 0.05）.（3）Spearman correlation analysis suggested positive correlation between Ty G and FPG,2h-PG and Hb A1 c at follow-up,the correlation coefficients were 0.271,0.288 and 0.215,respectively.TG/HDL-C was also positively correlated with FPG,2h-PG and Hb A1 c at follow-up,the correlation coefficients were 0.197,0.251 and0.149,respectively.Ty G correlated more strongly with glycaemic index than TG/HDL-C.（P< 0.05）.（4）Logistic regression analysis suggested that high levels of Ty G and TG/HDL-C were independent risk factors for T2 DM by adjusting for a number of confounding factors.The ORs for Q4 groups were 2.257 and 3.095,respectively.（5）The results of the ROC curve analysis suggested that Ty G was superior to TG/HDL-C as a risk marker in the total,in men,in women and in NGT groups,whose AUCs were 0.675、0.664、0.677 和 0.721,respectively.While TG/HDL-C was superior in the IGR group,whose AUC was 0.579.The best cut-off points for the incidence of T2 DM predicted by Ty G were 8.884,8.895,8.776,8.776 and 8.886 in the total population,men,women,NGT and IGR groups,respectively;and the best cut-off points for the incidence of T2 DM predicted by TG/HDL-C were 1.408,1.407,0.946,1.443 and 1.769,respectively.Conclusion: Elevated Ty G and TG/HDL-C levels are positively correlated with T2 DM,which are independent risk factors and good risk markers of the development of T2 DM.