Insulin Sensitivity And Insulin Secretion Of Simple Or Combined Hypertriglyceridemia With Impaired Glucose Regulation Before And After Intervention

Background: A large quantity of hypertriglyceridemia and normal glucose tolerance (NGT) can be found in people of physical examination, who may have impaired glucose regulation (IGR) through a physical examination again after a few years, even diabetes. Study at home and abroad show hypertriglyceridemia is an independent diabetic risk factors, also reveals lipotoxicity theory will affect insulin sensitivity and insulin secretion , and pancreatic islet function decompensation induces IGR,that is impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) even diabetes mellitus(DM). Therefore, to understand pancreatic islet function of hypertriglyceridemia still at NGT and IGR-stage and to find early signs of recession of islet function will have a greater significance. The main pathogenesis of type 2 diabetes is dysfunction of insulin resistance and insulin secretion, intervention to hypertriglyceridemia may improve insulin sensitivity and insulin secretion in order to prevent the progress of IGR even diabetes early.Part IObjective: To study insulin sensitivity and insulin secretion of simple or combined hypertriglyceridemia with impaired glucose regulation by true insulin and proinsulin.Methods: Screening of the people of physical examination having taken oral glucose tolerance test (OGTT), 62 cases of NGT and IGR with hypertriglyceridemia and 14 cases of healthy were chosen, asked about the family history of diabetes. Blood pressure, height, weight was measured and body mass index (BMI) was calculated. Blood glucose (BG) was measured at 0',30',120'by OGTT, at the same time, with detection of triglyceride (TG) and true insulin (TI), proinsulin (PI). The subjects were divided into three groups,①healthy control group:14 cases,②HTG group: 30 cases,③HTG+IGR group: 32 cases. Hypertension, obesity and other diseases are excluded from three groups. According to Homeostasis Model Assessment insulin resistance index (HOMA-IR), HOMAβ-cell function index (HOMA-β), acute insulin response (AIR) and PI 0/TI0,PI30/ TI30,PI120/ TI120 was calculated.Results: 1. There is no significant inter-difference in family history of diabetes among healthy control group, HTG group and (HTG+IGR) group. BMI in healthy control group is less than other groups, the difference is significant, P <0.01, while there is no difference between the other two groups;2. At 0',30',120', TI, PI levels follow an increasing trend of healthy control group, HTG group and (HTG+IGR) group, inter-group difference is significant, P <0.05-0.01;3. HOMA-IR follows an increasing trend of healthy control group, HTG group and (HTG+IGR) group, HOMA-βfollows reducing trend of the three groups, inter-group difference is significant, P <0.05-0.01, AIR of (HTG+IGR) group is less than the other two groups, the difference is significant, P <0.05.4. PI 0/TI0 follows an increasing trend of healthy control group, HTG group and (HTG+IGR) group, PI120/TI120 follows a declining trend of the three groups,inter-group difference is significant, P <0.05-0.01.Conclusion: Insulin sensitivity has decreased and insulin secretion has been redued in simple or combined hypertriglyceridemia with IGR. True insulin, proinsulin levels can be used as monitoring indicators of early changes in isletβ-cell function .Part II:Objective: The effect of treatment to glucose tolerance and insulin sensitivity , insulin secretion in simple hypertriglyceridemia by reducing triglyceride.Methods: Sxity-six cases of simple hypertriglyceridemia from people of physical examination were randomly divided into 35 people of intervention group and 31 people of control group. To advice lifestyle guidance and fenofibrate followed Xuezhikang treatment to intervention group, while the control group did not take any treatment. Before and after 2 years , fasting blood glucose (FBG), fasting TI (FTI), TC, TG, 2 hours blood glucose (2hBG), 2 hours TI (2hTI) was measured by OGTT in two groups. HOMA–IR was calculated according to Homeostasis Model Assessment. To compare some index before and after intervention.Results:1. Two years later, there is 11% (5 / 35) occurrence of IGR in the intervention group, non-occurrence of diabetes, there is 48% (15/31) of IGR and 3% (1 / 31) of diabetes in control group. There is significant difference in occurrence rate of abnormal glucose tolerance(IGR+DM)between intervention group and control group after intervention, x2 =12.6, P<0.01。2. In intervention group, TC, TG after treatment is less than before treatment, the difference is significant, P <0.05-0.01. In control group, there is no significant difference of TC, TG before and after 2 years.3. FTI, 2hTI, IR in intervention group after treatment is less than before treatment, the difference is significant, P <0.01. FTI, 2hTI, IR in control group has increased 2 years later, the difference is significant , P <0.05-0.01.Conclusion: Intervention to simple hypertriglyceridemia can prevent IGR and improve insulin secretion and insulin sensitivity.