A Review of Continuous Glucose Monitoring-Based Composite Metrics for Glycemic Control

Abstract

We performed a literature review of composite metrics for describing the quality of glycemic control, as measured by continuous glucose monitors (CGMs). Nine composite metrics that describe CGM data were identified. They are described in detail along with their advantages and disadvantages. The primary benefit to using composite metrics in clinical practice is to be able to quickly evaluate a patient's glycemic control in the form of a single number that accounts for multiple dimensions of glycemic control. Very little data exist about (1) how to select the optimal components of composite metrics for CGM; (2) how to best score individual components of composite metrics; and (3) how to correlate composite metric scores with empiric outcomes. Nevertheless, composite metrics are an attractive type of scoring system to present clinicians with a single number that accounts for many dimensions of their patients' glycemia. If a busy health care professional is looking for a single-number summary statistic to describe glucose levels monitored by a CGM, then a composite metric has many attractive features.

Response to Hulman and colleagues regarding “Glucotypes reveal new patterns of glucose dysregulation”

“…We and many others are working on this. Others are working on composite measures, which are not new ways of analyzing the data, but ways of combining summary variables from CMG data [ 2 ].…”

Diabetes Technology Meeting 2020

“…These include M 100 , BGRI, GRADE, and IGC calculated directly from glucose values, and Q-Score, CGP, and PGS calculated from mean glucose, %TBR, %TIR, %TAR, and glucose variability. [54][55][56][57][58] The Composite Glucose Monitoring Index is based only on three metrics: %TIR, %TBR, and standard deviation. 57 Although there are many available metrics, Figure 3 presents how only two metrics are truly needed.…”

Making sense of glucose metrics in diabetes: linkage between postprandial glucose (PPG), time in range (TIR) & hemoglobin A1c (A1C)

“…Attempts to develop a single composite metric for CGM have been made [46]. Ideally, a composite metric would summarize the features of CGM data with a number, allowing the physician to quickly determine the patient's glycemic control.…”