[Glucose excursion in senior patients with type 2 diabetes mellitus and coronary artery disease]

Objectives: To explore glucose excursion and incidence of hypoglycemia in senior patients with type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD) with different hemoglobin A1c (HbA1c) values. Methods: Eighty-nine outpatients [58 male, 31 female, aged 69.0 (66.0, 73.0) years] diagnosed with T2DM and CAD in Beijing Anzhen Hospital between June 2013 and March 2016 were divided into group A (HbA1c<6.5%, n=25) and group B (HbA1c≥6.5%, n=64). Every patient wore continuous glucose monitoring system (CGMS) for 72 h. Glucose excursion parameters and incidence of hypoglycemia from CGMS readings were calculated. Results: Compared with group B, patients in group A experienced shorter diabetes duration [8.0 (3.5, 15.0) vs 15.0 (8.0, 20.0) years, Z=-2.222, P=0.026], lower standard deviation (SD) of blood glucose from CGMS, mean amplitude of glycemic excursions(MAGE) and mean of the daily differences(MODD) (P=0.001, 0.003, 0.001). However, incidence of hypoglycemia was significantly increased [56.0% (14/25) vs 32.8% (21/64), χ(2)=4.051, P=0.044] in group A. Compared to those who had not experienced hypoglycemia, patients with hypoglycemia had higher SD [1.8(1.4, 2.4) mmol/L vs 1.4(1.1, 1.8) mmol/L, Z=-3.198, P=0.001] and MAGE [6.0(3.2, 7.4) mmol/L vs 3.9(2.7, 4.8 )mmol/L, Z=-2.768, P=0.006] which were appropriate tools for assessing intraday glycemic variability. No statistical difference were found in MODD which was the index for estimating interday glycemic variability. Conclusions: Intensive glycemic control in senior patients with T2DM and CAD had higher incidence of hypoglycemia. Those with hypoglycemia experienced greater intraday glucose excursion.