Improvements of ambient hyperglycemia and glycemic variability are associated with reduction in oxidative stress for patients with type 2 diabetes.

Aims: We aimed to evaluate which parameters of improvement in glucose metabolism reduce oxidative stress for patients with Type 2 diabetes mellitus (T2DM).

Methods: Sixty-seven outpatients with T2DM underwent 72 h of continuous glucose monitoring (CGM) and were measured for oxidative stress before and after a 24-week intervention with the following targets: fasting plasma glucose (FPG), <130 mg/dl; postprandial plasma glucose (PPG), <180 mg/dl; and glycated hemoglobin (HbA1c), <7% (53 mmol/mol). The mean glucose level (MGL), mean amplitude of glycemic excursions (MAGE), mean of daily differences (MODD), percentage coefficient of variation for glucose (%CV) and area under the postprandial plasma glucose curve (AUC) were calculated from the CGM data. Oxidative stress was estimated using the diacron-reactive oxygen metabolites (d-ROMs) test. Finally, the association between the improvements in glucose metabolism and oxidative stress was evaluated.

Results: FPG, MGL, HbA1c, MAGE, MODD, %CV, AUC, and d-ROMs significantly improved after 24 weeks of intervention. The change in d-ROMs was significantly correlated with that in FPG (r = 0.414), MGL (r = 0.402), HbA1c (r = 0.271), MAGE (r = 0.457), MODD (r = 0.371), and AUC (r = 0.352). The correlation of the change in d-ROMs with that in FPG, MAGE, and MODD and the use of glucose-like peptide 1 receptor agonists and statins remained significant after adjustment for other markers of diabetes control (multiple R = 0.406).

Conclusions: Improvements in glucose metabolism, including FPG and daily and day-to-day glucose variability, were all correlated with reduced oxidative stress for patients with T2DM.