The Relationship Between TyG Index And Mortality In Peritoneal Dialysis Patients

Background and ObjectivesCardiovascular disease is the main cause of death in dialysis patients.Insulin resistance(IR)is thought to be an important physiological pathology underlying the development of diabetes and cardiovascular diseases.Numerous studies have shown that IR is associated with an increased risk of hyperglycemia,hypertension and dyslipidemia,increasing the risk of inflammation,platelet aggregation and atherosclerosis.The current "gold standard" for evaluation of insulin resistance is high insulin positive glucose clamp test,but this method is complicated to operate,expensive,not widely used in clinical practice.At present,studies have proposed the reliability and landmark clinical indicators of triglyceride glucose index(TyG index)as insulin resistance(IR).A number of current studies have shown that TyG index is associated with the incidence of cardiovascular events in healthy people and has predictive value for cardiovascular disease.However,no similar reports have been reported in the long-term peritoneal dialysis(PD)population.The aim of this study was to analyze the risk factors for mortality in early clinical data and PD patients by collecting clinical data from long-term peritoneal dialysis patients and to analyze the relationship between triglyceride glucose index(TyG index)and long-term peritoneal dialysis patients with mortality,to help clinicians at the beginning of peritoneal dialysis in patients with high-risk patients at screening for early intervention.MethodsIn this study,519 incident patients on PD from 1 January 2007 to 31 December 2015 were recruited and followed up until 31 December 2016.Collect demographic and clinical data.Age,gender,body mass index,comorbidities,systolic blood pressure,diastolic blood pressure,residual renal function(RRF),dialysis time,peritoneal dialysis adequacy(Kt/V),and laboratory findings were recorded.The primary endpoint of this study was cardiovascular mortality and all-cause mortality.Statistical AnalysisTyG index was calculated as In[fasting triglycerides(mg/dL)×fasting glucose(mg/dL)/2].Participants were divided into two groups according to the median baseline TyG index:Low TyG group(TyG<8.44),High TyG group(TyG>8.44).Time-averaged TyG index(TA-TyG index)also divided into two groups:Low TA-TyG group(TA-TyG<8.49),High TA-TyG group(TA-TyG>8.49).The continuous variables that obey the normal distribution are denoted by Mean plus or minus standard deviation(Mean ± SD),and the continuous variables that do not follow the normal distribution are represented by the median.The classification variables are represented by a number(n)and a percentage(%).Independent sample t test or mann-whitney U test were used for continuous variables,and Pearson chi-square test or Fisher exact test was used for comparison between groups of categorical variables.Furthermore,Spearman rank correlation analyses was conducted to assess the relationship between baseline TyG index and risk factors.Survival rates was calculated using the Kaplan-Meier method,and the differences between distributions of survival were assessed by log-rank test.The association between TyG index and mortality was examined in Cox regression models.The Cutoff Finder software was used to calculate the cut-off point of the baseline TyG index for all-cause mortality and cardiovascular mortality in patients on PD.Statistical significance was defined as P<0.05 using two-tailed tests.Statistical analyses were performed using SPSS,version 20.0 for Windows(SPSS Inc.).ResultsOn multivariate Cox regression analysis,the higher group of the baseline TyG index(≥8.44)was associated with increased risk of all-cause mortality(hazard ratio(HR)2.22,95%confidence interval(CI),1.43-3.44;P<0.001)and CVD mortality(HR 2.50 95%CI,1.34-4.65;P=0.004).The relationship of time-averaged TyG index(TA-TyG index)and all-cause mortality and CVD mortality showed the similar trend(HR,1.90;95%CI,1.25-2.90;P=0.003;HR,2.05;95%CI,1.14-3.70;P=0.17,respectively).conclusionCardiovascular death is the leading cause of death in peritoneal dialysis patients.The triglyceride glucose index was associated to some extent with all-cause and cardiovascular deaths in long-term peritoneal dialysis patients and the higher baseline triglyceride glucose index predicted higher all-cause and cardiovascular mortality in long-term peritoneal dialysis patients.