Background
Frequent, large blood glucose fluctuations, or glycaemic variability (GV) may contribute to diabetes-related complications. We investigated the association between GV and metabolic health markers in individuals with prediabetes or untreated early-stage type 2 diabetes (T2D) participating in the PREDICT study.1
Methods
The data was collected at baseline. Laboratory-acquired glucose control measures included HbA1c, fasting, 1-hour and 2-hour plasma glucose following an oral glucose tolerance test (OGTT). Liver health markers included liver enzymes (AST, ALT, GGT), liver fibrosis and fat (FibroScan). Body mass and composition included BMI, waist-to-hip ratio (WHR), fat mass and visceral fat (VAT, dual-energy X-ray absorptiometry). Continuous glucose monitor (CGM, Abbott) was used for 14 days. CGM-derived variables were calculated (mean glucose, SD, IQR, maximum and minimum glucose, CV, continuous overall net glycaemic action [CONGA], mean amplitude of glycaemic excursions [MAGE] and mean absolute glucose [MAG]). Associations were assessed using the Spearman correlation coefficient.
Results
Out of 147 participants enrolled, 131 had high-quality CGM data (83 females, 97 had prediabetes and 34 T2D, average±SD age 55.2±10.5 years, BMI 31.8±6.1 kg/m2). The 1-hour OGTT glucose level exhibited the strongest association with SD, MAGE and IQR (r=0.718, r=0.704, r=0.688, respectively, p<0.001). Out of the liver markers, GGT was the strongest correlate of GV (mean glucose: r=0.288, p=0.0009; CONGA: r=0.269, p=0.002). VAT and WHR exhibited similarly significant associations with CONGA (r= 0.196 and r=0.184, p≤0.03, respectively) and mean glucose (r=0.202 and r=0.199, p≤0.02, respectively).
Conclusions
The 1-hour OGTT glucose and GGT were the strongest markers of GV. These easily acquired, yet underutilised variables may serve as a practical tool to assess GV in individuals with prediabetes or early-stage T2D.