The Relationship Of Fasting Plasma Cortisol, Malondialdehyde And Chronic Complications In Type 2 Diabetes Patients

Background and objective:Currently, diabetes (Diabetes mellitus, DM) has become the world's chronic diseases of highest morbidity and mortality. Along with the general improvement of living conditions, the number of people suffering from DM increases every year, the incidence of complications also showed a corresponding trend. Diabetes can cause cardiovascular disease, blindness, end-stage renal disease, non-traumatic amputations and other serious complications, seriously affecting the quality of life of patients or their families and create a heavy burden to the community. Therefore, enhance concernment and awareness on the factors that impact the occurrence and development of diabetes and advocate the integrated treatment have important clinical significance.This study was designed to explore fasting plasma cortisol, MDA levels and the relationship with chronic complications in type 2 diabetes and analyze the relevant factors. Then discuss with or without the difference between non-diabetic patients and diabetic patients about the function of pituitary-adrenal axis. This conduct will open up a new way to therapy the diabetes mellitus.Method:Choose 367 cases of patients with type 2 diabetes mellitus who unaffected by exogenous stress stimuli, then divided these patients into 2 groups depending on whether have the chronic complications. Diabetic patients without chronic complications as a group include 196 cases. Diabetic patients with chronic complications as another group include 171 cases.26 patients with type 2 diabetes to be used as the control group.91 cases of non-diabetic patients as control group. We should record the age,gender, disease duration, measure blood pressure, height, weight, and calculate body mass index (BMI) of all subjects, take the ipsilateral elbow blood in the 8am to measure fasting plasma glucose (FPG), total cholesterol (TC), glycerol three esters (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), plasma cortisol (FPC) and malondialdehyde (MDA). We measure the glycated hemoglobin (HbA1c), fasting insulin (Fins), urinary microalbumin, serum 132-microglobulin in the patients who have definitively diagnosed with T2DM. Calculate the insulin resistance index HOMA-IR=FPG×Fins/22.5,β-cell function index HOMA-β=Fins×20/(FPG-3.5). One main observative indicator of FPC was measured using magnetic enzyme-linked immunosorbent assay. MDA was measured using thiobarbituric acid method. Analyze the relevance of the indicators, conduct multi-factor Logistic regression analysis and then draw the ROC curve to evaluate the impact factors of type 2 diabetes suffering the major chronic complications.Results:①FPC and MDA levels of with chronic complications were significantly higher than patients without complications and non-diabetic group. The difference between the control group and without chronic complications group was not statistically significant(P<0.05).②The fasting blood glucose and 2 hours plasma glucose level of with chronic complication group was significantly higher than without complications group, and without complications group was significantly higher than the control group(P<0.05). Among the three groups, the difference of the blood pressure, blood lipids was not statistically significant (P<0.05).③The with chronic complications group has a higher rate of insulin therapy,a longer history of disease, a wider abdominal circumference and higher HbA1c, fasting insulin, urine microalbumin, serumβ2-microglobulin than without complications group.the difference was statistically significant (P<0.05). The difference among other indicators such as fasting plasma cortisol, and glycated hemoglobin, duration, abdominal circumference, insulin resistance index in three groups was not found. (P>0.05)④FPC levels of male patients was positively correlated with MDA (β=5.267, P=0.046); women FPC levels was positively correlated with MDA and pathogenesis (β=3.233, P=0.02;β=0.089, P=0.029 respectively).⑤MDA levels of male patients was positively correlated with FPC(β=0.055, P=0.013); women MDA level was positively correlated with age, DBP, FPC, and pathogenesis.(β=0.020, P=0.008;β=0.018, P=0.021;β=0.003, P=0.048;β=0.005, P=0.001,respectively).⑥Along with the number of complications of diabetes increase, the cortisol and the MDA level showed a rising trend among type 2 diabetes patients.⑦Logistic regression analysis showed that, after adjusting other variables FPC, duration, FPG, urinary albumin, MDA are the impact factors to diabetic chronic complications. To each of the diabetic complications specifically, results showed that MDA, FPC are the impact factors to the diabetic vascular disease; FPC, age, duration, HbA1c, FPG and MDA are the impact factor to the retinopathy; FPC, MDA, pathogenesis are the impact factors to the neurological disease; urinary albumin and MDA are the impact factor to the nephropathy. ⑧ROC curve prompted that the accuracy of using MDA to diagnose chronic complications is 86%. When MDA corrects to 7.755 the diagnostic value is the best(Sensitivity and specificity is 90.8% and 60.2% respectively). In with or without chronic complications group,95% CI of the MDA were 7.623～9.710 and 5.248～7.114 respectively.This interval is no overlap.Conclusion:Type 2 diabetes mellitus patients with chronic complications exhibit the disorder of the hypothalamus-pituitary-adrenal axis (HPA axis) adjustment function. Increased free radical injury the hippocampus, and suppress the HPA axis then cause the high plasma cortisol. High plasma cortisol and oxidative stress level both have adverse effects to the occurrence and development of diabetes and complications, also can increase the probability and severity of chronic complications. The oxidative stress indicator of malondialdehyde has a good value to diagnose the chronic complications. Monitoring and curing timely and appropriately, making cortisol and MDA maintained at a normal (or lower) range, will reduce the risk of suffering from various complications and make control diabetes to achieve a satisfactory result. Consequently, monitoring the level of cortisol and MDA in the diabetic patients have the great significance to delay the progress of type 2 diabetes.