The relation between plasma endothelin-1 levels and metabolic control, risk factors, treatment modalities, and diabetic microangiopathy in patients with Type 2 diabetes mellitus.

We evaluated the possible relation between plasma endothelin-1 (ET-1) levels and metabolic control, risk factors, treatment modalities, and diabetic microangiopathy, including nephropathy, neuropathy, and retinopathy in patients with Type 2 diabetes and healthy control group. Sixty-eight (39 females and 29 males) patients with Type 2 diabetes and 14 (6 females and 8 males) healthy subjects were included in the study. Plasma ET-1 levels were found to be 10.46+/-1.24 pmol/l in the diabetic group, whereas 7.97+/-0.41 pmol/l in the control group, which was statistically significant (P<.01). We also found elevated plasma ET-1 levels in patients with the least one microvascular complication when compared with the uncomplicated diabetes group (P=.02). Moreover, plasma ET-1 levels of the uncomplicated group was higher than the control group (P<.05). Plasma ET-1 levels were significantly elevated in hypertensive diabetics than normotensive diabetics (t=2.58, P=.012). It was also found to be elevated in diabetic patients with diabetes duration of more than 10 years when compared with patients less than 10 years (P=.02). These findings can be interpreted as the increased damage of microvascular complications in the disease process that may lead to elevated ET-1 levels. Mean plasma ET-1 levels in diabetic patients with a family history of diabetes was found to be higher than patients with no family history of diabetes. Genetical and environmental factors may have an effect on ET-1 level. We also studied the correlations of plasma ET-1 levels on age, sex, fasting blood glucose levels, treatment modalities HbA1c, hyperlipidemia, C-peptide, Body Mass Index, and smoking, but did not find any statistically significant difference. In conclusion, plasma ET-1 levels are well correlated with microangiopathy, hypertension, increased disease duration, and family history of diabetes, but poorly correlated with metabolic control, treatment modalities, age, sex, hyperlipidemia, obesity, and smoking.