Analysis of Continuous Glucose Monitoring in relation to HbA1c and Interstitial Fluid Glucose

The modern continuous glucose monitoring (CGM) devices can provide their users with a long sequence of interstitial fluid glucose concentration (ISF) measurements, taken at intervals of 1 to 15 min over a period of 7 to 14 days. These sequences of ISF measurements, generally called CGM traces, are a discrete representation of the continuous ISF. Analyzing these CGM traces and developing mathematical methods to unravel the underlying glucose-insulin dynamics from these CGM traces is an active field of research. In this manuscript we have developed two new methods of estimating the HbA1c of a type 2 diabetes mellitus (T2D) patient from the Indian population using their CGM trace. We validated these two new methods against a type 1 diabetes mellitus (T1D) CGM database and showed that one of these methods could also provide reliable HbA1c estimate for T1D patients from the Indian population. We then developed a new method, based on trajectory optimization, to estimate the continuous blood glucose concentration (BG) of an individual from their discrete ISF measurements, obtained from their CGM trace. We also developed a web application in MATLAB where any individual can upload their CGM trace and it will be analyzed and estimates of their continuous BG, HbA1c, and various other metrics can be obtained.