Associations between Hemoglobin Concentrations and the Clinical Characteristics of Patients with Type 2 Diabetes

BACKGROUND/AIMS: Many studies have demonstrated an association between hemoglobin levels and cardiovascular disease in diabetic patients. The aim of this study was to determine whether there is an association between hemoglobin concentrations and various clinical parameters, including metabolic factors, plasma C-peptide response after a meal tolerance test, and microvascular complications, in Korean patients with type 2 diabetes. METHODS: In total, 337 male patients with type 2 diabetes were recruited. All subjects were subjected to a meal tolerance test and underwent assessment of hemoglobin levels, fasting and postprandial β-cell responsiveness, and microvascular complications. RESULTS: Patients with lower hemoglobin concentrations had a longer duration of diabetes, a lower body mass index, and lower concentrations of total cholesterol, triglycerides, and low-density lipoprotein cholesterol. They also had lower levels of postprandial C-peptide, Δ C-peptide, and postprandial β-cell responsiveness. They had a higher prevalence of retinopathy and nephropathy. In multivariate analyses, there was a significant association between nephropathy and hemoglobin concentration. Also, hemoglobin concentrations were independently associated with Δ C-peptide levels and postprandial β-cell responsiveness. CONCLUSIONS: Hemoglobin concentrations are associated with postprandial C-peptide responses and diabetic nephropathy in patients with type 2 diabetes.