If I read every study about doom and gloom from diet choices, I’d curl up in the fetal position and cower in a corner somwhere.
I’m sorry. Maybe we can move this to a different thread. I’d forgotten we were still discussing this on your thread.
1 Like
In addition to all the variations discussed above, it’s important to understand that the A1C result from a blood testing lab has an error range too.
A certified lab’s results must be accurate within +/-6 % THat is to say that a number like 7 really can be anywhere from 6.58 to 7.42. It is not EXACTLY 7.
Some of the variation you see from test to test is just test error, not all BG changes.
That’s why it’s good to look at the longer term averages, rather than just a single 3 month number.
Katers - moving this to a different thread is probably a good idea as we are now in a debate on the best approach in reducing diabetes complications A1c or TIR.
As I mentioned above A1c is like average miles per hour if driving a car. To determine this you need a clock and odometer. TIR is like having a speedometer so you know how fast you are going at any given time. Doing 55mph in a 25mph zone may not be the best idea but without the speedometer you would have no idea how fast you are going at any given time. Thats A1c.
A1c is a historical test and it was cheap. It is still considered the gold standard per the ADA Standard of Care. Why? Simply put the SOC is outdated and will catch up in about 5 years, maybe sooner.
CGMs are still considered “new” technology even though you can go to any Walmart and get a Libre sensor for $40. Prior to the CGM measuring TIR was a big ordeal and getting an AGP was nearly impossible. Now, its easy. The SOC will catch up sooner or later, probably later.
Now, why is TIR important. There are a zillion studies showing elevated BG over 140 for 2hours or more is an issue. How big an issue is the question but its looking pretty big.
Here are older studies talking 140+ BG so we have know this for awhile but there was one released last Fall. I have the link some where.
Increased prevalence of impaired glucose tolerance in patients with painful sensory neuropathy. Singleton, JR Smith AG, Bromberg, MB Diabetes Care 24 (8) 1448-1453 2001.
The spectrum of neuropathy in diabetes and impaired glucose tolerance. C.J. Sumner, MD, S. Sheth, MBBS MPH, J.W. Griffin, MD, D.R. Cornblath, MD and M. Polydefkis, MD; Neurology 2003;60:108-111.
The spectrum of neuropathy in diabetes and impaired glucose tolerance. C.J. Sumner, MD, S. Sheth, MBBS MPH, J.W. Griffin, MD, D.R. Cornblath, MD and M. Polydefkis, MD; Neurology 2003;60:108-111.
Value of the Oral Glucose Tolerance Test in the Evaluation of Chronic Idiopathic Axonal Polyneuropathy. Charlene Hoffman-Snyder; Benn E. Smith; Mark A. Ross; Jose Hernandez; E. Peter Bosch. Arch Neurol. 2006;63:1075-1079.
Prevalence of Polyneuropathy in Pre-Diabetes and Diabetes Is Associated With Abdominal Obesity and Macroangiopathy Dan Ziegler et al. Diabetes Care 31:464-469, 2008
Krinsley, James, Effect of an Intensive Glucose Management Protocol on the Mortality of Critically Ill Adult Patients. Mayo Clinic Proc. Jan 2004, p. 992-1000.
Beta-cell deficit and increased beta-cell apoptosis in humans with type 2 diabetes. Butler AE, Janson J, Bonner-Weir S, Ritzel R, Rizza RA, Butler PC.Diabetes. 2003;52:102-110.
ß-Cell Death and Mass in Syngeneically Transplanted Islets Exposed to Short- and Long-Term Hyperglycemia. Montserrat Biarnés, Marta Montolio, Victor Nacher, Mercè Raurell, Joan Soler, and Eduard Montanya. Diabetes 51:66-72, 2002
Determinants of glucose toxicity and its reversibility in pancreatic islet Beta-cell line, HIT-T15.Catherine E. Gleason, Michael Gonzalez, Jamie S. Harmon, and R. Paul Robertson.Am J Physiol Endocrinol Metab 279: E997-E1002, 2000.
Inflammation markers and metabolic characteristics of subjects with one-hour plasma glucose levels. Gianluca Bardini et al. Diabetes Care Published online before print November 16, 2009, doi: 10.2337/dc09-134
1 Like
It is certainly an issue. Because it raises A1C.
2 Likes
Sam - but not if I go low for 2+ hours. It averages out.
With A1c you just don’t know. Its a nice starting point but provides little actionable information. If my A1c is 7, how high am I going after a glass of OJ and for how long? Whats my baseline. What foods do what, etc.
Back in the day when Richard Bernstein was a pharma engineer the gold standard was the monthly blood test diabetics would go in for. Richard the engineer quickly realized this was a complete waste of time. When no one would listen because he was not a doctor he went to medical school. Dr. Bernstein with his crude glucose meter with his constant finger pricks and food log was the first one to demonstrate the importance of TIR. In a few months he will be 85. Whatever he has done seems to have worked for him.
2 Likes
That’s not entirely accurate
I agree. A1c is not useful or actionable information in the immediate sense. But it’s the meaningful report card on the status of your disease. TIR is a management tool, it’s a very useful sort of information to act on and help manage, but it is certainly not an indication of the health of the cells in your body. Completely different things that really make no sense to compare directly.
1 Like
Sam - yes agreed, let me be a little more specific. The best tool is your AGP. From that you will determine TIR.
A non-diabetic will be at about 85 during fasting and seldom goes above 125 and is typically back to baseline in about 2 hours. Diabetes is really an engineering flow control problem which Richard Bernstein and Al Mann both figured out. Neither was a doctor but rather engineers.
Now the BIG question in the community is whats the ideal range for a diabetic. One would expect you would want to mimic a non-diabetic but you simply can’t with the antiglycemics and “insulins” prior to afrezza have been too dangerous for fear of hypos. What did they say at ADA2018 as the T1 baseline? Was it 180? Thats 40pts over the 140.
This article notes that the A1c test assumes that red blood cells live for 120 days. However, the life span of red blood cells can vary from 81 days to 146 days. Here’s a quote from the article.
The main problem is that there is actually a wide variation in how long red blood cells survive in different people. This study, for example, shows that red blood cells live longer than average at normal blood sugars. Researchers found that the lifetime of hemoglobin cells of diabetics turned over in as few as 81 days, while they lived as long as 146 days in non-diabetics.
This proves that the assumption that everyone’s red blood cells live for three months is false, and that hemoglobin A1c can’t be relied upon as a blood sugar marker. In a person with normal blood sugar, hemoglobin will be around for a lot longer, which means it will accumulate more sugar. This will drive up the A1c test result – but it doesn’t mean that person had too much sugar in their blood. It just means their hemoglobin lived longer and thus accumulated more sugar. The result is that people with normal blood sugar often test with unexpectedly high A1c levels.
I’m wondering if this could somehow explain why my A1c is often 0.5% higher than my glucose exposure.
The only way I am now at 6.7 & 6.8 is because I often allow myself to drift down into the 60s. Because of the fluctuations I have, I am satisfied with anything under 7.
Let’s not forget that the amount of AGEs alone is not enough. It is also necessary to take into account how variable the BG is. AGE damage happens all the time, to every human, diabetic or no. But, with low rate of AGE accumulation and low BG variability, the body can keep up with repairs. Wild BG swings prevent the body from repairing the damage.