Establishment of normal reference ranges for glycemic variability in Chinese subjects using continuous glucose monitoring

BACKGROUND: Glycemic variability is increasingly recognized as an important issue in diabetes management. However, the lack of normative values may limit its applicability in the clinical setting. The objective of this study was to establish preliminary normal reference ranges for glycemic variability by analyzing continuous glucose monitoring (CGM) data obtained from healthy Chinese adults. MATERIAL/METHODS: Three-day CGM data were obtained from 434 healthy adults at 10 academic hospitals throughout China. Glycemic variability was calculated as the 24-hour mean amplitude of glycemic excursions (MAGE) and standard deviations (SD) of blood glucose readings. RESULTS: 434 healthy subjects (male 213, female 221; age 43±14, 20–69 years old; BMI 21.8±1.7 kg/m(2), 18.5–24.9 kg/m(2)) completed the study. MAGE and SD values for the 434 healthy subjects were 1.73 (1.08) mmol/L and 0.75 (0.42) mmol/L [median (interquartile range)], respectively. In both men and women, MAGE and SD tended to increase with age. Neither MAGE nor SD showed a significant difference between men and women. Values for both parameters were non-normally distributed within the population. The 95(th) percentiles of MAGE and SD were 3.86 and 1.40 mmol/L, respectively. These values were adopted as the upper limits of normal. CONCLUSIONS: MAGE <3.9 mmol/L and SD <1.4 mmol/L are recommended as the normal reference ranges for glycemic variability in Chinese adults. The values established in this study may facilitate the adoption of glycemic variability as a metric of overall glycemic control in diabetes.