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If you use a CGM, do you look at the Glucose Management Indicator (GMI) available in many CGM reports? If so, how accurate is your GMI compared to your A1c drawn in a lab?
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My GMI is always lower than my A1C results
I’ve never heard of a GMI. I’ll have to look for it. I use T:Connect. If anyone knows where to look, let me know. Thanks.
I’m not sure it’s available on t:connect but it is on Dexcom Clarity.
Also a Tandem user. One thing I miss about my old Medtronic 670g is being able to casually scroll through my daily time in range pie charts and TIR stats. The Tandem pump itself doesn’t include very helpful CGM metrics. And the T:connect mobile app only allows to view the past 24 hrs. Unfortunately the Dexcom app stopped working on my Android phone too.
I looked on T:connect. It was not there. I stopped using Dexcom Clarity because I don’t use the Dexcom receiver any longer.
I just switch to Dexcom. Have not had a chance to compare yet
Use the Libre2 and this time was the biggest gap ever – Libre2 was 0.7 points higher than my A1C
Last GMI was 6.1 and blood test came back at 5.7. Month before said 6.1 and labs said 5.6. I’m going with lab values
My red blood cells tend to be a bit younger than normal due to anemia, which gives my hemoglobin less time to accumulate sugar. That lowers my A1c and makes my GMI a more reliable measure of my control.
I’ve very curious about the results of this one as it’s always puzzled me. My GMI is always 6.0 or 6.1 (for 30, 60, and 90 day averages) while my A1c is 5.3 or 5.4, so there is a significant difference.
Same here. The CGM GMI is always much higher that for a long time I didn’t realize it was meant to approximate A1C.
I was so excited by my GMI number two weeks ago. It was 5.9—the lowest it’s ever been. My A1c went up from 6.3 to 6.4. I don’t get it.
I just started recently looking at the report and hope it reflects in my future lab results.
I frequently look at the GMI. It varies from 6.8 to 7.0. My last lab A1C was 5.7. I suspect the reason is either my ongoing chemo or red blood cell imbalances due to severe anemia.
My GMI usually matches my A1c from Quest Lab. My GMI is consistently lower than my A1c from LabCorp.
My GMI is ALWAYS significantly higher than my A1C. Both with the G6 and the Libre3.
It’s interesting to see the differences! My Dexcom GMI is routinely higher than my A1C by at least 4 points.
Depending on the variance size between actual BG and SG, the GMI on TConnect can be substantially different than my A1C. Normally, it is close but not less than .4%
I dot have GMI on T connect but time in range is my best indicator of how I am doing. If I am at 80% in range or higher I am thrilled. and its pretty much staying that way.
How accurate depends on which lab ran the A1c. My primary MD and endo work under different organizations and use different labs. There can be a significant difference in the results. I’ve found my TIR to provide more useful information.
I attemp to keep my cgm within 20% of my meter. I use my cgm and clarity app for info…..not an a1c
My last GMI with Dexcom was 7.0% compared to my A1c of 6.1%
My Dexcom is the best CGM, but usually runs higher than the labs as my blood glucose varies incredibly during the day. It often needs to rest/shut down in order to catch up because of how quickly my glucose is fluctuating.
How did all this stuff get approved ???
Editors of this forum, thanks for asking this question. I’ve had a a Dexcom 6 for over a year, and now I think maybe I know what the GMI 0n pages 1 (overview) and 22 (compare) of the printout mean. If my GMI is 6.0 or 6.2 and my lab A1c is 6.1, then my GMI is certainly within 3% of my lab A1c. I still have things to learn about all the data available on the printout. Your questions help.