Postprandial glucagon-like peptide 1 secretion is associated with urinary albumin excretion in newly diagnosed type 2 diabetes patients

BACKGROUND: Microalbuminuria is an early and informative marker of diabetic nephropathy. Our study found that microalbuminuria developed in patients with newly diagnosed type 2 diabetes mellitus (T2DM). AIM: To investigate the association between glucagon-like peptide 1 (GLP-1) and microalbuminuria in newly diagnosed T2DM patients. METHODS: In total, 760 patients were recruited for this cross-sectional study. The GLP-1 levels during a standard meal test and urinary albumin-creatinine ratio (UACR) were determined. RESULTS: Patients with microalbuminuria exhibited lower GLP-1 levels at 30 min and 120 min during a standard meal test than patients with normal albuminuria (30 min GLP-1, 16.7 ± 13.3 pmol vs 19.9 ± 15.6 pmol, P = 0.007; 120 min GLP-1, 16.0 ± 14.1 pmol vs 18.4 ± 13.8 pmol, P = 0.037). The corresponding area under the curve for active GLP-1 (AUCGLP-1) was also lower in microalbuminuria patients (2257, 1585 to 3506 vs 2896, 1763 to 4726, pmol × min, P = 0.003). Postprandial GLP-1 levels at 30 min and 120 min and AUCGLP-1 were negatively correlated with the UACR (r = 0.159, r = 0.132, r = 0.206, respectively, P < 0.001). The prevalence of microalbuminuria in patients with newly diagnosed T2DM was 21.7%, which decreased with increasing quartiles of AUCGLP-1 levels (27.4%, 25.3%, 18.9% and 15.8%). After logistic regression analysis adjusted for sex, age, hemoglobin A1c, body mass index, systolic blood pressure, estimated glomerular filtration rate, homeostasis model assessment of insulin resistance, AUC(glucose) and AUC(glucagon), patients in quartile 4 of the AUCGLP-1 presented a lower risk of microalbuminuria compared with the patients in quartile 1 (odds ratio = 0.547, 95% confidence interval: 0.325-0.920, P = 0.01). A consistent association was also found between 30 min GLP-1 or 120 min GLP-1 and microalbuminuria. CONCLUSION: Postprandial GLP-1 levels were independently associated with microalbuminuria in newly diagnosed Chinese T2DM patients.