Relationship between daily and day-to-day glycemic variability and increased oxidative stress in type 2 diabetes

Abstract Aims To determine the association of daily and day-to-day glucose variability with oxidative stress. Methods This was a cross-sectional analysis of 68 patients with type 2 diabetes mellitus (T2DM) over 72 h of continuous glucose monitoring. Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) were measured before breakfast on day 1. Glucose variability, mean glucose level (MGL), mean amplitude of glycemic excursions (MAGE), mean of daily differences (MODD) in glucose levels and area under the postprandial plasma glucose curve (AUC PP ) were measured on days 2 and 3. Plasma oxidant capacity against N,N-diethylparaphenylenediamine was measured with the diacron-reactive oxygen metabolites (d-ROMs) test on day 1. Results Overall, 66.2% males with the mean age of 63.2 ± 12.6 years, diabetes duration of 12.9 ± 10.4 years, and HbA1c level of 8.1 ± 1.6% (65 ± 17 mmol/mol) were included. MGL ( r  = 0.330), HbA1c ( r  = 0.326), MAGE ( r  = 0.565), MODD ( r  = 0.488), and AUC PP ( r  = 0.254) exhibited significant correlations with d-ROMs and not FPG; these correlations remained significant after adjustment for clinical factors (sex, age, duration of diabetes, smoking habit, insulin use, statin use, angiotensin II receptor blocker use, BMI, LDL-C, HDL-C, TG, eGFR, and systolic blood pressure) ( R 2  = 0.268, R 2  = 0.268, R 2  = 0.417, R 2  = 0.314, and R 2  = 0.347, respectively). MAGE was significantly correlated with MODD ( r  = 0.708) and MAGE and MODD were independently correlated with d-ROMs by multivariate analysis. Conclusions Therefore, oxidative stress is associated with daily and day-to-day glucose variability in patients with T2DM.