Continuous glucose monitoring is showing the limitations of HbA1c


Continuous glucose

monitoring is showing up

the limitations of HbA1c,

which is just a summary of

control over a three-month


" Time in range (TIR) generally refers to

the time spent in an individual's target

glucose range (usually 3.9-10mmol).

TIR measurements add valuable

information to assess the level of current

glycaemic control in addition to what

is known from the HbA1c. However,

clinicians, researchers, and regulators

now know that time in target range

alone is not an adequate description

of overall glycaemic control. It is also

necessary to quantify the times below

and above target range, using a few

severity thresholds for each level. Thus, time in 'ranges' (TIRs) provide a more useful

metric for clinical and research purposes.

TIRs are useful for a research comparison of interventions and can help

patients understand whether the amount of clinically significant hypoglycaemia or

hyperglycaemia they are experiencing is improving over time. Isolating and counting

the time in hypoglycaemia and hyperglycaemia into level 1 (monitor and take action if

needed) and level 2 (immediate action required due to the more potentially clinically

significant nature of the glucose levels) can guide the urgency and degree of clinical


Because the function of CGM use is to monitor glucose levels with the ultimate

goal of improving glycaemic control, it makes clinical sense to combine TIRs data

with other measures. HbA1c level and time in level 2 (clinically significant/immediate

action required) hypoglycaemia is one such combined measure. Time in target range

combined with time in level 2 hypoglycaemia is another such combined measure.

Ideally, the way to use TIR measurements is to assess and report the percentages

of time in ranges (target, hypoglycaemia, and hyperglycaemia). Different TIRs in

conjunction with a measure of glycaemic variability should be reported as key

diabetes control metrics in clinical studies.


continued over HEALTH ECONOMICS &


According to an article on Diabettech, "In order for the discussion about using

CGM and TIR to become standard in diabetes care, in order to move into the

mainstream CGM technology has to come down in price. Manufacturers need

to sell their products as Gap not Gucci. We get that it's not cheap to develop

the products, but if, instead of having a consumer base of 3% of the global

T1D population, you had 40% of the population, then the cost could become

a lot lower."

To read the full article, click

reading of 7% might be spending a lot of

time in hypo and having a miserable time.

Also it is only designed to measure mean

[average] glucose. It's hard for users to

correlate an HbA1c target with day-today

readings via blood tests, or even

via CGM. Time in range is much more

understandable, and therefore in many

ways more useful for patients. It's good

to be able to tell them that not all blood

tests will be bullseyes."

Getting better

The fact remains that not all diabetics

are getting access to (or are paying for)

CGM, but you can get pretty much the

same results using blood tests to see

how much time you spend in range. Says

Choudhary, "An HBA1c of 8% has a mean

Variability - going up, going

down - is problematic.

Improve on that, and it all

gets better.""


  1. Desang diabetes magazine diabetes information
  2. Dexcom CGM, continuous glucose monitoring
  3. Desang diabetes magazine diabetes information, Sue Marshall
  4. Desang diabetes magazine diabetes news
  5. Diabetes UK Nutrition Guidelines, Medtronic insulin pump CGM packages
  6. Verily, CGM for T2, Medical ID jewellery, Ascensia Diabetes Challenge
  7. Leicester Diabetes Centre, JDRF, Rachel Connor JDRF, T1Exchange
  8. Diabetes kit diabetes management equipment
  9. Omnipod Insulet insulin pump with insulin pods
  10. Desang diabetes magazine diabetes diet
  11. Desang diabetes magazine diabetes diet
  12. Accu-Chek Mobile blood glucose system
  13. Accu-Chek Mobile blood glucose system
  14. The tyranny of HbA1c time to talk now about Time in Range
  15. The fallacy of average, why HbA1c isn't good enough
  16. ADA Consensus Report Outcome Measures Beyond HbA1C for Type 1 Diabetes
  17. hypoglycaemia, hyperglycaemia, time in range
  18. patient quality of life
  19. Continuous glucose monitoring is showing the limitations of HbA1c
  20. HbA1c, mean glucose, Time in Range
  21. Ascensia Contour Next One Diabetes blood test meters
  22. My Diabetes Kit Debbie Green
  23. My Diabetes Kit Debbie Green, Accu-Chek Roche, Medtronic
  24. My Diabetes Kit Debbie Green, Accu-Chek Roche, Medtronic
  25. London Medical, London Diabetes Centre, private diabetes clinic
  26. Spirit Healthcare, Chris Barker, Leicester, Empower
  27. Spirit Healthcare, Chris Barker, Leicester, Empower
  28. Making Carbs Count chickpeas
  29. Making Carbs Count chickpeas
  30. Accu-Chek Insight insulin pump
  31. Accu-Chek Insight insulin pump
  32. Page 0032

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