Correlations between Glucagon Stimulated C-peptide Levels and Microvascular Complications in Type 2 Diabetes Patients

Abstract

BackgroundThis study aimed to investigate whether stimulated C-peptide is associated with microvascular complications in type 2 diabetes mellitus (DM).MethodsA cross-sectional study was conducted in 192 type 2 diabetic patients. Plasma basal C-peptide and stimulated C-peptide were measured before and 6 minutes after intravenous injection of 1 mg glucagon. The relationship between C-peptide and microvascular complications was statistically analyzed.ResultsIn patients with retinopathy, basal C-peptide was 1.9±1.2 ng/mL, and stimulated C-peptide was 2.7±1.6 ng/mL; values were significantly lower compared with patients without retinopathy (P=0.031 and P=0.002, respectively). In patients with nephropathy, basal C-peptide was 1.6±0.9 ng/mL, and stimulated C-peptide was 2.8±1.6 ng/mL; values were significantly lower than those recorded in patients without nephropathy (P=0.020 and P=0.026, respectively). Stimulated C-peptide level was associated with increased prevalence of microvascular complications. Age-, DM duration-, and hemoglobin A1c-adjusted odds ratios for retinopathy in stimulated C-peptide value were 4.18 (95% confidence interval [CI], 1.40 to 12.51) and 3.35 (95% CI, 1.09 to 10.25), respectively. The multiple regression analysis between nephropathy and C-peptide showed that stimulated C-peptide was statistically correlated with nephropathy (P=0.03).ConclusionIn patients with type 2 diabetes, the glucagon stimulation test was a relatively simple method of short duration for stimulating C-peptide response. Stimulated C-peptide values were associated with microvascular complications to a greater extent than basal C-peptides.

The pharmacokinetics of porcine C‐peptide after intraperitoneal injection

“…In fact, the value of C 0 after the low‐dose intravenous injection was approximately 2000 pmol/L (~0.6 ng/mL), and the value after the high‐dose intravenous injection was approximately 15 000 pmol/L (~4.5 ng/mL). Therefore, the value of C 0 after the low‐dose C‐peptide injection was similar to the basal C‐peptide concentration and the high‐dose C‐peptide injection was similar to the stimulated C‐peptide concentration …”

Relationship Between β-Cell Function, Metabolic Control, and Microvascular Complications in Type 2 Diabetes Mellitus

“…In contrast to these studies in T1DM, data on the relationship between C-peptide and type 2 diabetes mellitus (T2DM) were controversial. Some studies [5][6][7][8][9] showed that C-peptide had a positive influence on chronic vascular complications in patients with T2DM, whereas others did not. 10,11 Previous studies used fasting or postprandial C-peptide levels as a surrogate of b-cell function.…”

Independent association between serum C‐peptide levels and fat mass‐to‐lean mass ratio in the aging process

“…Epidemiological studies have reported that serum C‐peptide level is an independent risk factor for cardiovascular disease, cancer and total mortality . It is significantly elevated in individuals with high BMI and metabolic syndrome, and might also be related to glucose transport and the stimulation of microvascular blood flow . Several studies have shown that serum C‐peptide and serum insulin levels increase with age.…”