We believe that TIR should be the primary glucose metric for daily management, complemented by A1C, in diabetes care globally.
A1C has been the gold standard for assessing glucose control for more than three decades. Like A1C, TIR has also been associated with reduced risk of developing diabetes-related complications. While A1C is commonly used as an average measure of blood glucose over a span of 2-3 months, it does not capture glucose variability which can affect the health of people with diabetes. Moreover, it does not capture the variable occurrence of hypoglycemia and hyperglycemia. In fact, two people with the same A1C results could have very different glucose profiles. The positive correlation between A1C and TIR further reinforces the need to move beyond the A1C measurement as the sole marker of glycemic control.
TIR goes beyond A1C in analyzing blood glucose levels because it provides a more complete picture of glycemic control, including the percent of time glucose levels are in target range as well as the percent of time levels are high and low (we call this Time Below Range and Time Above Range). TIR, together with TBR and TAR, provides a more complete picture of glucose levels and has the potential to reveal patterns of hypoglycemia and hyperglycemia throughout the day and night. TIR can tell a personalized and individual story about glucose levels, helping people with diabetes to understand both their daily fluctuations and what is driving them, and helping healthcare professionals make more informed decisions for better diabetes management.
The diagram below is an example of three different people with diabetes, all who have an A1C of 7%. As you can see, the example on the left has dangerous highs and lows while the person on the right is 100% in-range. High and low blood sugars can impact energy levels, moods, and can cause serious health complications in the short and long term. A1C alone does not capture the overall picture of glycemic control but with the addition of TIR, people with diabetes can have the information they need to take control of their diabetes.
