Liraglutide effects on beta‐cell, insulin sensitivity and glucose effectiveness in patients with stable coronary artery disease and newly diagnosed type 2 diabetes

AIMS: The aims of the study were to investigate the effects of the GLP-1 receptor agonist liraglutide as add-on to metformin on insulin sensitivity (Si) and glucose effectiveness (Sg) in addition to its positive effects on beta-cell function in overweight/obese patients with coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM). METHODS: The design of the study was a randomized, double-blind, placebo-controlled, cross-over trial in patients with stable CAD and newly diagnosed well-controlled T2DM. Patients were treated with liraglutide/metformin vs placebo/metformin for a 12 + 12-week period with ≥2-week wash-out. First phase insulin secretion (AIRg), Si and Sg were estimated by the Bergman Minimal Model, enabling calculation of beta-cell function; Disposition Index (DI) = AIRg × Si. A total of 30 patients from among 41 randomized were available for paired analysis. RESULTS: × min (IQR 342; 626, P < .0001) and DI by 1-fold, 766 (SD 824, P < .0001). Despite a significant weight loss of -2.7 kg (-6.7; -0.6) during liraglutide treatment, we found no improvement in HOMA-IR, Si or Sg. Weight loss during liraglutide therapy did not result in a carry-over effect. CONCLUSION: Liraglutide as add-on to metformin induces a clinically significant improvement in beta-cell function in overweight/obese, high cardiovascular risk patients with newly diagnosed well-controlled T2DM and CAD. The effect of liraglutide on DI is mediated entirely by improved AIRg whereas the effects on Si and Sg are neutral.