Read about Time in Range (vs A1C), and why the latest FDA draft guidance document is so important.
Full article
Or follow the discussion on Instagram:
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@MsCris Good afternoon, at least where I am. I have long been interested in this metric, I hade good article from the last international diabeties conference where this was a big topic, But alas I canât find it, But here is good article by the ADA on this also.
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Yes! I believe I cited/used this, or itâs update, for my article (sources listed at the bottom).
What I posted is a reader-friendly article, more for the masses.
My personal issue with ADA had been itâs very wide TIR, which does cause complications at an A1C of 7%.
Microvascular damage starts at A1C of 5.7% and greater. So my article includes the latest evidence showing that a TITR of 50% time in 70-140 mg/dL, which is closer to normoglycemia, may be a goal for those who have steadily improved.
Plus, the FDA now proposing to allow CGM metrics for labelling in antidiabetic drugsâŚthat could be a game changer for T1D therapies (while a cure is developed).
Thanks for the discussion @T1john !
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@MsCris Thanks for posting this. Interesting article! While my Endo, probably like most, depends on A1c, he also uses TIR along with SD and COV and over the last year seems to have pushed more to TIR, SD, and COV. All are useful, but I tend to focus on TIR and have gone to the extent of changing the range from 70-180 down to 70-140, seeking improvements over time (months).
Being a relative new come to T1, I marvel at the slowness to change by the FDA. If it takes 15 years to their next change, I probably wonât be alive to see it! Seems kind of crazy theyâre not more up-to-date.
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I think the 70-180 TIR is a little bit over-simplified.
Suppose someoneâs blood sugar was flat and stayed at 178 for the entire time.
Hey, I was in range 100% of the time!
But in actuality, nobody would really be happy with that.
As another example, I think it is better to pop up to 200 for only 30 minutes and then quickly drop back down below 140, than it would be to stay at 160 for several hours. But staying at 160 would reflect as a better time in range than the short excursion to 200.
Honestly, which of those 
would you prefer?
I think the whole TIR target thing could be better defined.
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Iâm curious why âTime Above Range, Highâ is defined as >180. When using Clarity to look at TITR, a user will track a TIR based on 70-140 or thereabouts and Dexcom Clarity will report a percent âHighâ as everything above the range (>140). So for a user to track Time above 180 would not be a simple task using Dexcom Clarity, that percentage is not readily available without changing the range. BUT tracking Time Above Range for >140 is a simple task for the TITR user. So why not define âTime Above Range, Highâ as Time above whatever range a user is tracking?
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That is part of Clarity and reports can be generated to ID what you asking for.
You can customize reports.
@Eric Then read the article, because it discusses that exactly! With graphical examples.
@Sjwprod Yes, Clarity is an app for Dexcom, that produces the AGP report. The AGP report is what is discussed in the article.
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@John58 the âacceptedâ TIR is set to 70-180 - what Drs look at because that is the clinically accepted range for most with diabetes.
I agree, itâs lla limiting factor in the AGP report.
My personal TIR is 70% in 65-140 day, 65-125 night. Above that, my AGP shows it âhighâ. Unfortunately I canât set the âvery highâ to anything but 250! Wish I could!
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@TomH I was SHOCKED when that draft guidance came out. Iâm 6 years into T1D, and I come from a regulated industry with guidance was updated at least every 5 years.
That FDA draft is a big deal - comments make a difference! Comment as simply as:
âT1Ds deserve better therapies than insulin alone - using CGM metrics to demonstrate safety profiles and efficacy is crucial to our quality of life.â
Link to do that is at the end of the article.
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@MsCris Good morning, I use the TTIR of 80-140 all the time, and run from 70-90% TIR. and have to say I never noticed that Dexcom uses 250 as very high and canât be adjusted. To me 200 is very high, when I get to 180 I am eating hard to stop rise.
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@T1john youâre similar to me! I have a nonlinear/logarithmic response to insulin - like most everything in nature. The higher I am, the more insulin I need.
I do not comprehend why the automated systems donât allow for this response, so I donât use them - they just donât work!
I get headaches that quickly go to migraines if I canât get down quickly. I have an alert set to 115 to pay attention, so I can decide on the trend and IOB.
I can hit 130/140 for a very short time and even by then I have a headache. If I canât get down within a half hour (and Novolog takes 35 minutes to act in me), Iâm in a migraine, muscle and joint aches, eyes burning. Itâs an awful cycle.
Yeah, I wish âvery highâ were adjustable in AGP. But at least our âhighâ is!
I did read it, which is why I posted my comment. I would not post a comment without reading the article.
Here it is, the 180 they referenced:
The ADA, ATTD, EASD, and ISPAD each have recommendations, with a goal of at least 70% time spent in the range of 70-180 mg/dL for most people with diabetes.
Metric Definition Category Blood glucose (mg/dL) Goal
TIR Time in Range Target Range, living with diabetes 70â180 >70%
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OHHH! 
@Eric I totally misunderstood your comment! 
my bad!
Forgive me, English is not my first language, tone gets lost in text sometimes! 
(And I think my tone of encouraging you to read the article got lost, too!)
Please let me know if the below conveys that I got your point:
70-180mg/dL was set pre-CGM when we had only A1C and some finger sticks per day, and wanted to keep insulin-users safe from hypoglycemia. Why? because A1C measures only time spent in hyperglycemia - not an average (itâs estimated), and not hypoglycemia.
The DCCT trial was pre-CGM, yet was still able to extrapolate a bit of TIR based on that limited data - unlike todayâs ton of CGM data.
And exactly to your point, I do argue why TIR and A1C should be used together via the graphical examples because at 70-180âŚTIR alone canât predict A1C very well at all. The 2 metrics together are a more complete picture.
But until more clinicians accept that tighter ranges are achievable with CGM without severe hypoglycemia, weâre often stuck with them comparing to the accepted âstandard range.â Like in the AGP report.
And if you donât have a CGM (like still so many with diabetes), your clinician has only the A1C test to go by, thus that range.
From now on, more emojis all around from me! 
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@MsCris My reaction time to novolog is same, and have duration at 2 hours, which is close for normal bolus,I have delayed stomach emptying, Gastritis?, but anyway donât always know when my food will hit so when I start rising I start bolloxing at around 130 and every 45 minutes there after, or sooner if rising fast, which enenturawly leads to it going low, hence my mistake of starting eating at 160, which is on down ride afterwards if thereâs a high amount of IOB and how much and or how often I bolused. and yes I pre bolus but normally only half and will put in manual for the unbolted portion plus the hourly rate of basal in the previous 1hour, to calculate hourly dose and set timer for 1.25 hours, to either change manual rate or return to automated, and I use the Omnipod 5 and Dexcom G-6.
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Iâm so sorry that you deal with gastroparesis! I canât imagine how difficult that is on you and managing your t1d. I wish there were more/better treatments for it.
Novolog lasts only 2.25 hours after injection - similar again.
My best to you in battling your T1D! 
Hi @MsCris
This was somewhat challenging for me to express in a simple manner. In general, they are saying that you should try to be between 70-180 over 70% of the time.
And that is fine, except that my point is simply to say - if someone is at the higher end of that 180 number, but still below 180, they could still be in range. But that is not the best result.
So I used the example of saying that if you stayed at 178 all the time, you would be hitting the 70% of the time metric.
A more complicated metric, which I have seen, is to say something like
greater than 50% of the time you are between 70-140
less than 20% of the time, you are between 140-180
less than 5% of the time, you are over 200
etc, etc.
I donât recall all the exact metrics, but that is the general idea. That it gives you more exact numbers and time percentages than just lumping it all together into a single 70-180 grouping.
I hope that makes sense.
And yes, absolutely! I have been making these same points for many years, even to endocrinologists! The A1C is not an average, as many people (and even many endocrinologists have described!).
And the A1C does not measure lows, only highs or the absence of highs.
And yes, I 100% agree with that! Using them both is much better.
Itâs wonderful that you are able to communicate in multiple languages! You are doing great!
I can only speak English, and some might make the point that I donât even do a good job with only that single language! 
But it sounds like we are in agreement with these points. 
Thank you for your reply!
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Would like to add my endo basically uses the AGP, I have mentioned my A1C going down and he was like oh really, i donât much look at them have to have for your reports i send in i really get what i need from your AGP.
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I totally agree with you. My A1c is 5.6 and TIR 87%. My TIR is 60-180. So TIR shows a lot of lows. But 65-69 is perfectly normal for me. We are all different. Hard to put us in a box.
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