Objective: To investigate the characteristics of glycemic excursions in people with normal glucose tolerance (NGT) in Chengdu.
Methods: A total of 50 non-obese people with normal glucose tolerance (NGT, 23-68 years old), normal blood pressures and lipid profiles participated in the study. The fluctuations of glucose levels in the participants were measured by a continuous glucose monitoring system (CGMS) for three days 72 h. The 48 h mean blood glucose (MBG), mean amplitude of glycemic excursions (MAGE), Largest amplitude of glycemic excursions (LAGE), Postprandial peak glucose (PPG), Postprandial glucose excursion (PPGE), Mean of postprandial glucose excursion (MPPGE), and absolute means of daily differences (MODD) were measured.
Results: The number of glucose values detected by CGMS amounted to 861+/-7 with a mean absolute difference (MAD) of 11.3%+/-10.6%. The CGMS values were significantly correlated with the capillary glucose measurements (n=1076, r=0.761, P<0.005). The participants had a MBG of (5.9+/-1.2) mmol/L, a MAGE of (1.7+/-0.7) mmol/L, a LAGE of (4.4+/-1.9) mmol/L, a daily glycemic peak (PPG) of (8.7+/-1.7) mmol/L, a nadir level of (4.3+/-0.7) mmol/L, a MPPGE of (2.3+/-1.6) mmol/L, and a MODD of (0.75+/-0.79) mmol/L. The post-breakfast Postprandial glycemic excursions (PPGE) were lower than those of post-lunch and post-dinner (P=0.01 and P=0.05). The postprandial glucose excursions in the 60-70 year-old participants were the highest (P<0.022). In 95% (77%-100%) of the daytime, the glycose levels fluctuated between 4.1 and 8.8 mmol/L, and 78% of the participants (n=39) had hyperglycemia (BG>7.8 mmol/L) and 10% (n=5) had asymtomatic hypoglycemia (BG<2.8 mmol/L).
Conclusion: CGMS tests may be important for detecting asymptomatic hyperglycemia and hypoglycemia. The NGT people in Chengdu have exhibited abnormal blood glucose values in CGMS, revealing problems in people with normal range of blood glucose.