Digital Health
Digital technology is advancing in every aspect of life and managing diabetes is no exception
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3 min. read
Using Time in Range (TiR) and HbA1c together to help manage your diabetes
Find out how you can use both these glucose metrics together to get a better grip on your diabetes.
Together with HbA1c, Time in Range can help you and your healthcare professional to get a more complete picture of your blood glucose over time and help reduce your risk of health complications.1,2
HbA1c gives your average glucose levels over three months and Time in Range adds to this by giving you results over 24-hour periods.1
HbA1c is a traditional and useful measure of blood glucose for diabetes management but there are some things it cannot show, such as the daily fluctuations that can be responsible for low glucose (hypoglycaemia) or high glucose (hyperglycaemia). For people who use a continuous glucose monitor (CGM) device, the peaks, dips and daily fluctuations in glucose can be seen.1
Read on to find out how Time in Range can work together with HbA1c to provide a more complete picture of your glucose levels and how your diabetes management is going.1
This quick-reference guide shows you how to read Time in Range from a special report on your CGM
A three-month average versus a 24-hour picture
HbA1c is a useful measure that shows you your average blood glucose levels over the previous three-months.1 HbA1c is generally seen as the ‘gold standard’ in diabetes management and has been used for a long time.2 It is the best-known and best-studied measurement, but some scientists are starting to think that Time in Range could be a better indicator of your risk of diabetes complications over time.1,2,5
Time in Range can show you the daily fluctuations in your glucose levels so you can see all the peaks and dips. HbA1c cannot show you this detail.1–3 In fact, people with the same HbA1c results could have very different glucose patterns.4,6
Here is an example:
Two people with the same HbA1c results can have different glucose patterns.
Both Peter and Christina appear to have good diabetes glucose management, as their HbA1c test results were both 7%. But a closer look shows a different picture.6 This extra information is vital to help make those small but important lifestyle and behaviour changes needed to live well with diabetes.1
Short animation of the differences between Time in Range and HbA1c
Time in Range gives a more complete picture of your glucose management; a personalised view that shows how long you spend in your target glucose range (between 70 and 180 mg/dL or 3.9–10 mmol/L, for most people). Experts recommend that most people with type 1 or type 2 diabetes, should try to spend at least 17 hours (70%) of their day in range. Different people may have slightly different targets for both HbA1c and Time in Range and your doctor can tell you what your personal target range is.1
Time in Range and HbA1c work together to help reduce diabetes health risks
Repeated periods of high glucose (hyperglycaemia) will increase the risk of diabetes-related health problems. The more time you spend above and below range (Time above range and Time below range), the greater your risk of health complications such as damage to your eyes and kidneys, and even heart attack or stroke.2,3
HbA1c can be used to predict your risk of developing these health complications and aiming for an HbA1c of below 7% can reduce this risk.2
In addition, the more time you spend in range, the more likely you are to reduce your diabetes health risks.1,3
Time in Range means fewer finger pricks
HbA1c and Time in Range are measured differently. HbA1c is measured using a blood glucose test which must be sent to a laboratory.3,4 Time in Range is measured during your everyday life using the numbers from a continuous glucose monitoring (CGM) device.1 A CGM device checks your ’interstitial’ glucose levels without you having to prick your finger or take any blood, using a sensor attached to your body.2 Interstitial glucose sounds complicated, but all it means is that the monitor measures glucose in the fluid under your skin rather than directly in your blood.2 The recent dramatic advances in digital health for diabetes and ‘diabetes tech’ have proved that using a CGM device can be very successful in helping people with diabetes stay within their target glucose range.7
Time in Range and HbA1c are both useful tools
Time in Range is not replacing HbA1c, but it can provide extra information to help support you and your healthcare professional to manage your diabetes.1,2,4 Independent qualitative research conducted to explore what people with diabetes think about using Time in Range indicates that this extra information can improve motivation for self-management and positive lifestyle changes.8 Some people who were accustomed to using a CGM device and reading their Time in Range said that seeing their personal glucose patterns helped them be more effective in managing their diabetes.8
Both Time in Range and HbA1c are very helpful tools to support you and your diabetes care team to make informed decisions that work for you and your health now and in the future.
This free CGM Cheat Sheet gives you the basics about starting with a CGM device and Time in Range
References
- Battelino T, Danne T, Bergenstal RM, et al. Clinical Targets for Continuous Glucose Monitoring Data Interpretation: Recommendations from the International Consensus on Time in Range. Diabetes Care 2019;42(8):1593–1603.
- Danne T, Nimri R, Battelino T, et al. International Consensus on Use of Continuous Glucose Monitoring. Diabetes Care 2017;40(12):1631-1640.
- Lu J, Wang C, Shen Y, et al. Time in Range in Relation to All-Cause and Cardiovascular Mortality in Patients With Type 2 Diabetes: A Prospective Cohort Study. Diabetes Care. 2021; 44(2):549-555.
- Chehregosha H, Khamseh ME, Malek M, et al. A View Beyond HbA1c: Role of Continuous Glucose Monitoring. Diabetes Ther. 2019; 10(3):853-863.
- American Diabetes Association Standards of Medical Care in Diabetes 2023. Diabetes Care. 2023; 46 (Supplement 1): S1–S292.
- Kovatchev B, Cobelli C. Glucose variability: Timing, Risk, Analysis, and Relationship to Hypoglycemia in Diabetes. Diabetes Care 2016; 39: 502–510.
- Peek N, Sujan M, Scott P. Digital health and care in pandemic times: impact of COVID- BMJ Health Care Inform 2020;27(1):e100166.
- Novo Nordisk. Data on file: TIR Patient Qualitative Research Global Summary Report. Data collection 2021–2022.
