Blood sugar question?

[DSeid]

This article might also be of interest.

The same person might be labelled as haivng prediabetes by one measure and not another.

Increased levels of glycemia in the prediabetic range, measured by fasting or postchallenge glucose or by A1C can serve as simple and reasonably accurate predictors of subsequent type 2 diabetes risk (1). Above and beyond its association with diabetes, hyperglycemia at the prediabetic level is associated with increased risk of subsequent cardiovascular disease (2–5). The value of glycemic measures is further strengthened by evidence that diabetes risk can be reduced with structured lifestyle interventions and/or metformin among individuals with levels of glycemia above normal but below the diagnostic threshold for diabetes (6–8). This means that measures of glycemia can serve as practical indicators for referral to diabetes prevention programs. …

… In a representative sample of the U.S. adult population, the prevalence of those at high risk of diabetes varied greatly by the indicator used to measure risk. For example, the prevalence of prediabetes as measured by IFG100 (26.2%) was almost twice that measured by A1C5.7 (14.2%) and IGT (13.7%) and over three times that of IFG110 (7.0%). The combination of either A1C5.7 or IFG100 resulted in a prevalence of almost 33%. … Our findings confirm prior observations that considerable discordance between A1C, IFG, and IGT exists, and that the characteristics of individuals identified at risk for diabetes vary by risk indicator. This has implications for prevention programs concerning who will be identified and enrolled in prevention efforts. A1C5.7 may disproportionately identify non-Hispanic blacks, while IFG may disproportionately identify men. Due to the lack of a gold standard for comparison, it is unknown whether these measures are biased or whether these groups are actually at a higher or lower risk of developing type 2 diabetes …

That last bit is key. Roughly 1/3 of adult Americans would have prediabetes by at least one of methods. Right now we have no reason to believe that one is more specific of future risk (of diabetes or cardiovascular complication) than any other. Which hits the … sweet spot, shall we say … for both missing and overcalling the least or at least in the best balance? Is the current definition calling everyone with a fasting glucose of 100 or more “prediabetic” excessively pathologizing or good case-finding? It is a reasonable debate.

[OleOneEye]

@WhyNot

I’ve never heard anyone saddled with the label for a single 103 reading.

Years ago, my insurance company saddled me with that diagnosis for a single 101 reading. Every so often they still like to send me “helpful” reminders about managing my “diabetes”. :mad:

[Amberlei]

Because so many variables (activity level, infection, other medications, etc.) can affect blood sugar levels, I don’t think a single reading should be enough to make a definitive diagnosis. Multiple readings, staggered throughout the day, over a period of a couple weeks, would give a more accurate understanding.

[jabiru]

@Hari_Seldon

In the US, it is measured in mg/deciliter. In the rest of the world (or, at any rate, in Canada) it is measured in mmoles/liter.

Any idea why? I get that the US won’t go metric but mg/decilitre is metric so why the difference in the way BSL is measured?

I’ve also never been able to work out why US cholesterol levels are so very different from the ranges I’ve seen here. I guess it must be for a similar reason.

[DSeid]

Sorry to be overly posting here but these questions get me wondering about things and I suspect that others might be interested in some of what I find as a result:

1. Clearly there are abnormalities that precede these markers labeled as prediabetes. As common as they are, things have been going in the direction awhile before you get to impaired fasting blood glucose, abnormal HgbA1c, or an abnormal oral glucose tolerance test. Different abnormalities though are associated with different markers. What that means prognostically and in terms of intervention remains to be seen.

2. Physical activity is somewhat protective from the adverse cardiovascular risks associated with insulin resistance even among those with the same level of insulin resistance. IOW insulin resistance is strongly predictive of adverse outcomes in sedentary males at least but not so predictive if the men are physically active.

So HoneyBadgerDC even if you test the same low level of “pre-diabetes” after a period of increased activity you are still substantially reduceing the risk of serious adverse impact from it.

[HoneyBadgerDC]

@DSeid

Sorry to be overly posting here but these questions get me wondering about things and I suspect that others might be interested in some of what I find as a result:

1. Clearly there are abnormalities that precede these markers labeled as prediabetes. As common as they are, things have been going in the direction awhile before you get to impaired fasting blood glucose, abnormal HgbA1c, or an abnormal oral glucose tolerance test. Different abnormalities though are associated with different markers. What that means prognostically and in terms of intervention remains to be seen.

2. Physical activity is somewhat protective from the adverse cardiovascular risks associated with insulin resistance even among those with the same level of insulin resistance. IOW insulin resistance is strongly predictive of adverse outcomes in sedentary males at least but not so predictive if the men are physically active.

So HoneyBadgerDC even if you test the same low level of “pre-diabetes” after a period of increased activity you are still substantially reduceing the risk of serious adverse impact from it.

I appreciate your posts, thank you.

[amanset]

@WhyNot

The US and most of Europe uses a scale of milligrams of glucose in a deciliter (100 milliliters) of blood, and normal is 70-120. The UK uses a scale of millimoles of glucose in a liter of blood, and normal is 4-6. There are conversion calculators available online.

For the record, this isn’t very true. Europe uses mmoll pretty much exclusively. The other, American, way of doing things is seen as a bit weird.

/amanset
Type 1 since 1993.
Haven’t lived in the UK since 1999.

[Hari_Seldon]

@jabiru

Any idea why? I get that the US won’t go metric but mg/decilitre is metric so why the difference in the way BSL is measured?

I’ve also never been able to work out why US cholesterol levels are so very different from the ranges I’ve seen here. I guess it must be for a similar reason.

Yes, it is the same reason. I once looked up the molecular weight of cholesterol and worked out the conversion factor, but I have forgotten what it was. As for why, I have no clue. Let me speculate that it was a similar impulse to why the US will not adopt metric. No international organization is going to tell me how to run my business. Incidentally, the A1C is the same all over; it is just a percent, the percentage of hemoglobin in the blood that is bound in a glucose complex (glycosalated). It is essentially a long term average since it changes slowly. Oddly enough it tends to be numerically the same as blood glucose measured in mmole/l. My last measurements were A1C 5.6% and glucose level 5.7 mmole/l.