Dipeptidyl peptidase-4 (DPP-4) inhibitors enhance glucose-induced insulin secretion, decrease glucagon secretion, and might effectively reduce blood glucose variability.  This is investigated in the Continuous Glucose Monitoring (CGM) substudy of CAROLINA^®, an ongoing, cardiovascular outcome trial comparing linagliptin with glimepiride.  To explore potential relationships between glycemic variability (assessed with CGM, Dexcom SEVEN PLUS) and circulating markers of glucose variability (1.5-AHG), oxidative stress, endothelial function, and systemic inflammation, we analysed the baseline glucose excursion patterns and assessed whether glycemic variability was correlated with five vascular markers.  Specifically, we characterized the baseline ambulatory glucose profiles with glucose exposure (by total area under the curve), glucose variability (by inter-quartile range), and glucose stability (by the average hourly absolute change) of all CGM readings in 2-week periods.  Mean ± standard deviation age of the 44 patients with type 2 diabetes was 66 ± 9 years and HbA1c 7.0 ± 0.4%.  A modest, significant negative correlation between glycemic variability and 1.5-AHG was observed, but not for vascular markers (Table).  Future analysis of the prospective CAROLINA^® CGM substudy will determine if glimepiride and linagliptin have differing impact on glycemic excursions patterns.

This study was sponsored by Boehringer Ingelheim.