Time in range: a new parameter to evaluate blood glucose control in patients with diabetes

Abstract

The International Consensus in Time in Range (TIR) was recently released and defined the concept of the time spent in the target range between 70 and 180 mg/dL while reducing time in hypoglycemia, for patients using Continuous Glucose Monitoring (CGM). TIR was validated as an outcome measures for clinical Trials complementing other components of glycemic control like Blood glucose and HbA1c. The challenge is to implement this practice more widely in countries with a limited health public and private budget as it occurs in Brazil. Could CGM be used intermittently? Could self-monitoring blood glucose obtained at different times of the day, with the amount of data high enough be used? More studies should be done, especially cost-effective studies to help understand the possibility of having sensors and include TIR evaluation in clinical practice nationwide.

Impact of Switching from Intermittently Scanned to Real-Time Continuous Glucose Monitoring Systems in a Type 1 Diabetes Patient French Cohort: An Observational Study of Clinical Practices

“…19 While this hypothesis needs to be explored, both points taken together might suggest that a change in TIR could be mostly related to postprandial hyperglycemia and/or the dawn phenomenon rather than posthypoglycemic hyperglycemia. 7,20 We also noted an inverse linear association between the change in TIR and the change in GMI, confirming the idea that TIR is a reliable marker of chronic exposure to hyperglycemia, usable in current practice. 7,20 Conversely, the strong positive linear association found between the change in interstitial glucose %CV and the change in TBR (<70 mg/dL) suggested that the reduction in %CV was mainly explained by the decrease in exposure to hypoglycemia over 6 months.…”

“…7,20 We also noted an inverse linear association between the change in TIR and the change in GMI, confirming the idea that TIR is a reliable marker of chronic exposure to hyperglycemia, usable in current practice. 7,20 Conversely, the strong positive linear association found between the change in interstitial glucose %CV and the change in TBR (<70 mg/dL) suggested that the reduction in %CV was mainly explained by the decrease in exposure to hypoglycemia over 6 months. This is in accordance with the %CV being the most descriptive AGP metric for hypoglycemia excursions.…”

Individualizing Time-in-Range Goals in Management of Diabetes Mellitus and Role of Insulin: Clinical Insights From a Multinational Panel

“…For people using CGM, TIR is defined as the time spent in the target glucose range (70–180 mg/dL) while aiming at reducing the time spent in hypoglycemia. TIR serves as an outcome measure for glycemic control in clinical trials, for complementing other components such as HbA 1c and blood glucose levels [ 37 ].…”

“…Categorization of the time spent in the three levels of hypoglycemia and hyperglycemia allows a more accurate assessment of severity and facilitates initiation of the most appropriate response [ 14 , 37 ].…”

Log-linear relationship between endogenous insulin secretion and glycemic variability in patients with type 2 diabetes on continuous glucose monitoring

“…Continuous glucose monitoring (CGM) is able to track the changes in glucose concentration throughout the day and permits the assessment of glycemic variability (GV) 2 . CGM-based studies have shown that GV instability is not only associated with higher risks of hypo- and hyperglycemia 3 , but also of the onset and progression of diabetes-related microvascular 4 – 6 , and macrovascular complications 7 , 8 . Therefore, antidiabetic treatment strategies should be aimed at reducing GV.…”