A study on the association of serum 1,5-anhydroglucitol levels and the hyperglycaemic excursions as measured by continuous glucose monitoring system among people with type 2 diabetes in China

BACKGROUND Blood glucose excursion is an important component of the glycaemic burden, but there are no indexes that can directly reflect them. The aim was to evaluate the values and significance of serum 1,5-anhydroglucitol (1,5-AG) in people with type 2 diabetes mellitus in China and to elucidate the relationship between 1,5-AG and traditional indexes of glycaemic excursions by continuous glucose monitoring. METHODS A total of 576 healthy adults and 292 patients were included, and their 1,5-AG, fasting blood glucose and postprandial blood glucose and glycated haemoglobin were measured. For the 34 patients, their mean blood glucose, standard deviation of blood glucose, mean amplitude of glucose excursion, mean of daily differences, low blood glucose M-value index and the area under the curve for blood glucose above 180 mg/dL were calculated by use of a continuous glucose monitoring system. RESULTS Serum levels of 1,5-AG among healthy adults were 28.44 ± 8.76 µg/mL with a significant gender bias rather than age bias. The 1,5-AG levels in people with type 2 diabetes mellitus were 4.57 ± 3.71 µg/mL, which were lower than those seen in the healthy adults. There was a correlation between 1,5-AG and glycated haemoglobin, fasting blood glucose, and postprandial blood glucose (r = -0.251, -0.195 and -0.349, respectively; all had p < 0.05). The continuous glucose monitoring system demonstrated that 1,5-AG presents a negative correlation with mean blood glucose, standard deviation of blood glucose, mean amplitude of glucose excursion and mean of daily differences for 7 days and with the area under the curve for blood glucose above 180 mg/dL on the third, fourth and seventh days. CONCLUSIONS 1,5-AG may serve as a marker of hyperglycaemia and 7-day hyperglycaemic excursions as well as being a useful adjunct to glycated haemoglobin for blood glucose monitoring in patients with diabetes.