*Geek Box: Glycaemic Variability
Numerous blood glucose measures may be used in research, and if you have an interest in diabetes research, you’re going to come across a head-spinning number of different measures, which fall under the broad definition of “glycaemic variability” [GV]. In simple terms, GV is the swings in blood glucose levels that occur throughout the day. GV includes the elevations in blood glucose that occur after a meal, the time spent with high or low blood glucose levels, as well as the difference in blood glucose responses at the same time of day, on different days. GV is a normal aspect of physiology; otherwise healthy people have blood glucose fluctuations throughout the day. However, in diabetes, the level of GV can be increased.
Several measures have emerged. HbA1c is the most well-known, which is a marker of longer-term glycaemic control, over the preceding 2-3 months. The mean amplitude of glycaemic excursion [MAGE] is used as a measure of the glucose excursions in response to meals. There is also the continuous overall net glycaemic action [CONGA], which assesses the variability of glucose levels within a specified time window. These tools provide for a more thorough picture of glucose regulation, and this is important, because GV itself appears to be related to diabetic complications. However, while it is tempting to see GV as an important therapeutic target, the exact value of targeting GV specifically is yet to be fully determined.