Indices of beta‐cell function: association with diabetes control in patients with type 2 diabetes on stable GLP‐1 agonist treatment

Abstract

AbstractThe aims of this study were to investigate the association between metabolic factors and glycaemic control in patients with type 2 diabetes on glucagon‐like peptide‐1 (GLP‐1) agonists, and explore the physiological reasons for less good glucose control in some patients compared to others.We conducted a cross‐sectional study of 26 patients with type 2 diabetes and HbA1c ranging from 5.7–11% (39–97mmol/mol), on GLP‐1 agonists with oral hypoglycaemics for at least four months. A liquid meal tolerance test was performed and samples for plasma glucose, insulin and C‐peptide were taken at 0, 30 and 120 minutes. Glucagon was measured in the fasting state. Insulin secretion and resistance indices were correlated with HbA1c using Pearson correlation coefficient.We found a significant correlation between HbA1c and indices of beta‐cell reserve (HOMA B: r = ‐0.53, p < 0.05; Insulinogenic 30 Index: r = ‐0.46, p < 0.05; Disposition Index 30: r = ‑0.53, p < 0.05; and 120 minute C‐peptide: r = ‐0.4, p < 0.05). We did not observe any significant correlation between glycaemic control and fasting glucagon nor with HOMA IR.Indices of beta‐cell function, but neither insulin sensitivity nor fasting glucagon, are associated with diabetes control in long‐term GLP‐1 treated patients with type 2 diabetes. This has important implications for the management of individuals who fail to achieve target glycaemic control on GLP‐1 agonists.