ADA Time in Range Guidelines: What They Are, Their Importance and How This Affects Diabetes Educators
Jul 11, 2019, 12:54 PM
by Neesha Ramchandani, PNP, CDE
In June 2019, the American Diabetes Association published its first recommendations for time-in-range (TIR) targets when using continuous glucose monitoring (CGM) in research and practice (Battelino et al., 2019). The recommendations were developed by an international panel of 43 physicians, researchers, and individuals with diabetes who are experts in CGM technologies and diabetes research and care in order to provide guidance for clinicians, researchers, and individuals with diabetes to utilize, interpret and report CGM data in routine clinical care and research. To ensure the recommendations are generalizable and comprehensive, the consensus panel included individuals living with diabetes and had international representation from physicians and researchers from all geographic regions (Kirkwood, 2019).
The recommendations made by the expert panel are outlined in Table 1.
Table 1. Time-in-range (TIR) recommendations for continuous glucose monitoring (CGM) data.
| Diabetes Type | Glucose Range | Recommendations (% of readings; time per day |
| Type 1/type 2 diabetes | <54 mg/dl (<3.0 mmol/L) | <1% (<15 min) |
| <70 mg/dl (<3.9 mmol/L) | <4% (<1 h) |
| 70-180 mg/dl (3.9-10.0 mmol/L) | >70% (>16 h, 48 min) >60% for individuals <25 yrs old (>14 h, 24 min) |
| >180 mg/dl (>10.0 mmol/L) | <25% (<6 h) |
| >250 mg/dl (>13.9 mmol/L) | <5% (<1 h, 12 min) |
| Older/high risk type 1/type 2 diabetes | <70 mg/dl (<3.9 mmol/L) | <1% (<15 min) |
| 70-180 mg/dl (3.9-10.0 mmol/L) | >50% (>12 h) |
| >250 mg/dl (>13.9 mmol/L) | <10% (<2 h, 24 min) |
| Pregnancy with type 1 diabetes | <54 mg/dl (<3.0 mmol/L) | <1% (<15 min) |
| <63 mg/dl (<3.5 mmol/L) | <4% (<1 h) |
| 63-140 mg/dl (3.5-7.8 mmol/L) | >70% (>16 h, 48 min) |
| >140 mg/dl (>7.8 mmol/L) | <25% (<6 h) |
| Pregnancy with gestational or type 2 diabetes | 63-140 mg/dl (3.5-7.8 mmol/L) | >90% (>21 h, 36 min) |
Source: Battelino, T., et al., 2019
Spending 70% TIR corresponds to a HbA1C of 7.0%; an increase or decrease of 10% TIR corresponds to a change in HbA1C of approximately 0.5% in the same direction (60% TIR = HbA1C of around 7.5%, etc.) (Battelino et al., 2019).
The Importance of Using TIR:
HbA1C alone does not provide enough information about an individual with diabetes’ day-to-day diabetes management (Battelino et al., 2019), nor is it a value that individuals with diabetes try to access without a clinician-initiated blood test. Using TIR as a metric by which to evaluate diabetes management provides a more realistic picture of what is going on day-to-day, and also empowers individuals with diabetes to take control of their own diabetes in between follow-up visits because they can easily access this information. Additionally, TIR is a more accurate measure than HbA1C for assessing glycemic control in certain people who have conditions that may confound HbA1C values, such as iron deficiency or other anemias, hemoglobinopathies, and pregnancy (Battelino et al., 2019). Furthermore, a recent analysis of data from the Diabetes Control and Complications Trial (DCCT) showed that TIR by itself is strongly associated with the risk of microvascular diabetes complications (Beck et al., 2019). Therefore, using the more tangible TIR along with HbA1C can help decrease an individual’s risk of developing microvascular complications.
How this Affects Diabetes Educators:
Diabetes educators like using TIR to help their patients because it provides targets which are “understandable and actionable. It’s also a much more positive goal to strive for” (Dr. Tim Bailey, from (Close & Brown, 2017)). It has also been called a “better ‘quality’ measure of glucose management” (Gary Scheiner, CDE, from (Close & Brown, 2017)) because it captures both hypoglycemia and hyperglycemia (Battelino et al., 2019; Close & Brown, 2017) and provides a platform for discussing glycemic variability.
TIR informs HbA1C and is an easier metric to use to make adjustments to diabetes medications and lifestyle interventions. It provides valuable information that a HbA1Cdoes not, enabling the diabetes educator to make important treatment adjustments even for those with a HbA1C that is in the target range. TIR can also be used to make adjustments when no HbA1C is available, such as when the bloodwork is taken during the visit and sent to the lab or was last done several weeks to months before the appointment with the diabetes educator, and in cases where the HbA1Cvalue may not be truly representative of the individual’s blood glucose values (e.g., for sickle cell anemia). Like looking at a BG average, TIR is something that individuals with diabetes can be educated to assess on their own, which can empower them to make their own changes. Monitoring TIR enables people with diabetes to see the effects of small changes in real time rather than waiting for their next HbA1C to be checked, which can help motivate them to either continue doing well or make additional changes to their therapeutic regimen. It may also be easier to educate individuals with diabetes about the effects of their actions on their sugars by using TIR. For those whose insurance will not cover personal CGM, professional CGM can be used to periodically obtain TIR data.
Even though the recommendations for TIR give specific values and percentages, there is a general consensus that TIR should be individualized based on the individual and their current life circumstances, it may change over time, and that time spent in hypoglycemia (recommended for most as <4% of time or <1 hour per day) should not be overlooked (Close & Brown, 2017).
Acknowledgements: The author would like to thank Julia Blanchette, RN, BSN, CDE, for her assistance with editing this article.
For more key learnings from the ADA Scientific Sessions, check out posts from AADE members Hope Warshaw and Chris Memering.
References:
Battelino, T., Danne, T., Bergenstal, R. M., Amiel, S. A., Beck, R., Biester, T., . . . Phillip, M. (2019). Clinical Targets for Continuous Glucose Monitoring Data Interpretation: Recommendations From the International Consensus on Time in Range. Diabetes Care. doi:10.2337/dci19-0028
Beck, R. W., Bergenstal, R. M., Riddlesworth, T. D., Kollman, C., Li, Z., Brown, A. S., & Close, K. L. (2019). Validation of Time in Range as an Outcome Measure for Diabetes Clinical Trials. Diabetes Care, 42(3), 400-405. doi:10.2337/dc18-1444
Close, K., & Brown, A. (2017). CGM and Time-in-Range: What Do Diabetes Experts Think About Goals? Diatribe Dialogue. Retrieved from https://diatribe.org/cgm-and-time-range-what-do-diabetes-experts-think-about-goals. Accessed July 2, 2019.
Kirkwood, M. (2019). New Recommendations for Time-in-Range Targets During Continuous Glucose Monitoring Presented Today at the ADA’s Scientific Sessions [Press release]. Retrieved from http://www.diabetes.org/newsroom/press-releases/2019/new-recommendations-for.html. Accessed July 2, 2019.