Latest HbA1c and surgery review

[JITR]

So why does the NHS NICE website rrcommend 48 as the target value?
My GP tells me that is the preferred value for type 2 patients, whereas the 20-41 range is for non-diabetic patients. Is that right?

This histogram from University of Groningen (2011) may help to explain why the international consensus of diabetes experts decided on 48 mm/mol. It also indicates why 35-41 mm/mol is a good target range for those who can do better (mean 38+/-3).
See: https://pure.rug.nl/ws/portalfiles/portal/14502679/01c1.pdf

 

[Bruce Stephens]

This histogram from University of Groningen (2011) may help to explain why the international consensus of diabetes experts decided on 48 mm/mol.

There's also good evidence that the risks of complications is far from linear with HbA1c, and as HbA1c gets down to 48ish it's close to flat: going lower reduces complications but not by that much. So getting down to that sort of level is the most important thing.

 

[EMcKT]

I am quite new to all of this but have been on Metformin since diagnosis late February. Have had none of the seemingly usual side effects but my B12 has already dropped under the normal range. Recommendation is to have it tested again in three months when I shall ask to have all bloods repeated. Experiencing a bit of 'toe tingling' some days as well as general aches and pains in muscles. Keeping a close eye.

 

[Docb]

View attachment 30843
This histogram from University of Groningen (2011) may help to explain why the international consensus of diabetes experts decided on 48 mm/mol. It also indicates why 35-41 mm/mol is a good target range for those who can do better (mean 38+/-3).
See: https://pure.rug.nl/ws/portalfiles/portal/14502679/01c1.pdf

As you know I like a good graph and I am a bit intrigued by this one because I cannot figure out how the data were derived. I suspect that the term non-diabetic meant people who were not diagnosed as T1 and not diagnosed T2 by whatever standards were in place at the time(1989) in the country where the cohort lived. At least that is the sense I get from a quick read of the paper it comes from.

 

[Eddy Edson]

As you know I like a good graph and I am a bit intrigued by this one because I cannot figure out how the data were derived. I suspect that the term non-diabetic meant people who were not diagnosed as T1 and not diagnosed T2 by whatever standards were in place at the time(1989) in the country where the cohort lived. At least that is the sense I get from a quick read of the paper it comes from.

You're misreading the dating. The "1989" date refers to the earliest in a list of cites. The histogram is from the last cite, a large Dutch cohort biobank called LifeLines which started in 2006 & continues to collect follow up data. https://academic.oup.com/ije/article/44/4/1172/667081

Dunno when the histogram was produced.

 

[JITR]

Dunno when the histogram was produced.

It came from a paper dated 2011, a forerunner of an article published a year or two later which excluded the histogram. Will put up the references later.

 

[Eddy Edson]

It came from a paper dated 2011, a forerunner of an article published a year or two later which excluded the histogram. Will put up the references later.

I guess this is the later paper? https://onlinelibrary.wiley.com/doi/full/10.1111/joim.12010

Anyway, it describes how the histogram sample was selected:

The study population was derived from the LifeLines Cohort Study, an observational follow-up study in a large representative sample of the population of the three northern provinces of the Netherlands including three generations 20. All participants completed a number of questionnaires and underwent a medical examination at baseline, and are being followed longitudinally with extensive standardized measurements. The study was approved by the Ethics Committee of the University Medical Centre Groningen.

Recruitment has been ongoing since the end of 2006, and since April 2009 the oldest unrelated subject(s) from each family have been selected for inclusion in the GWAS. For this study, we selected 3367 unrelated participants of western European descent who underwent the baseline medical examination, completed the questionnaires and from whom genome-wide data of good quality were available. We excluded participants with diabetes mellitus (n = 156), either self-reported or diagnosed by a fasting plasma glucose (FPG) ≥7.0 mmol L−1. In addition, we excluded participants with significant anaemia (n = 86), defined by a haemoglobin level <8.2 mmol L−1 for men and <7.0 mmol L−1 for women, and those without an HbA1c value (n = 13), erythrocyte measurements (n = 10) or FPG (n = 181). The final study population comprised 2921 nondiabetic adults.

Just on the basis of that description, maybe the sample skews older, which might be a reason for the mean HbA1c of 38, higher than the ~35 level I've seen reported from a number of other studies.

 

[Docb]

Thanks for the input @Eddy Edson and @JITR . Seemed to me that you could only construct such a curve if you could exclude from the cohort anybody who had diabetes. They did that by removing anybody with a diabetes diagnosis and anybody with a fasting glucose >7 mmol/l. The second criterion would have been the standard diagnosis method used in the Netherlands at the time. If you did it these days with diabetes diagnosed by HbA1c levels >47 then one tail of the distribution would be truncated. Interestingly, not a lot would have been eliminated and I doubt the mean and SD would have shifted much.

Either way up, it is one way of illustrating the range of HbA1c you might expect to see in people functioning perfectly well and as such help to give a perspective to those presented with a number without any context.

 

[Sussexmax]

As far as I can see, the medication should not prevent you achieving remission at a later date provided that your diabetes is well managed and you are not putting your beta cells under undue pressure by eating more carbs than they can cope with. I think remission is less achievable if diabetes is long term and poorly managed, so I don't think you are less likely to achieve remission by ticking over as you are with medication for another year when your HbA1c is in the normal range.

Thanks for your advice and suggestions as well as identifying possible ways forward. Thought I’d mull it over for a couple of weeks rather than acting hastily. In the end I’ve decided to leave things as they are and stay on the meds until the next test in about a year. Think it’s partly because I don’t want to ‘rock the boat’, but also partly because I see them as ‘support’ that I’ve come to rely on. Presumably our bodies become accustomed/acclimatised to being on meds, and no doubt that’s already the case with me and metformin. Wonder whether over time that becomes a ’need’ more than just a support?