Lesson #22: "The Human Gap"

Stephen W. Ponder MD, FAAP, CDCES


In the era of continuous glucose monitoring (CGM), staying “in range” competes with the hemoglobin A1c as the most desired result of quality diabetes self-management. Why this shift in focus? In February 2019, the Advanced Technologies & Treatments for Diabetes (ATTD) Congress convened an international panel of physicians, researchers, and individuals with diabetes who are expert in CGM technologies to address this issue.


The International Consensus in Time in Range (TIR) group recommended persons using CGM strive to achieve blood sugar levels between 70-180 mg/dL at least 70% of the day. Furthermore, values below 70 mg/dL should be less than 5% of the day and over 180 mg/dL should be less than 25%.


The image below show TWO different 3 month time windows highlighting the consistency of TIR, average blood sugar and variability (standard deviation) using MDI-based Sugar Surfing™


Clinical studies now emphasize improved time in range as a primary outcome of hybrid closed loop insulin delivery devices. These high-tech devices are numerous now. They include several commercial versions and even more flexible DIY systems. Common to all systems is the machine-based ability to use patient CGM data to automatically adjust delivery rates and doses to achieve optimal TIR.


As more studies are published, it’s clear that these devices are a step (or leap) forward compared to standard insulin pumps with or without a CGM worn by the user. The ability to meet the 70% recommendation is now possible. Without these systems, TIR ranges were often far below the 70% minimum target.