Is a lower HbA1c always better?

The study says this:

“The observed CVD risk among people with low HbA1c levels and no known diabetes is particularly important, because this increased risk could not be related to hypoglycemia11 “

They’ve reached the exact opposite conclusion.

" Furthermore, the patterns of the association between low HbA1c levels and each CVD subset differed from that for diabetes or high HbA1c levels. Low HbA1c levels were associated with an increased risk of stroke, especially hemorrhagic stroke, while diabetes and high HbA1c levels were associated with increased risks of coronary heart disease and stroke, especially ischemic stroke. The observed CVD risk in individuals with diabetes in this study was also consistent with accumulating evidence of diabetes as a risk factor for CVD.26,27 These findings emphasize a possible increased CVD risk among people without known diabetes and with low HbA1c levels. "

No conclusion is made regarding people with diabetes with low HbA1c levels. This is likely because the study inclusion criteria required that none of the individuals were diagnosed with diabetes. I assume that after their first A1c came back above a certain range, they were advised of their diagnosis, but I’d need to read the study a bit more to determine that.

[Edit: The study has one subgroup of individuals originally diagnosed with diabetes, but they do not list their hazard ratios or information by HbA1c. In addition, it looks like they only managed to obtain HbA1c information from 65% of all the individuals only at baseline. As A1c can change quite a bit for D people, that seems very insufficient and not particularly helpful].

The study’s limitations state:

" our results may not be applicable to other populations, especially Western populations, because East Asians tend to have a higher incidence of stroke and lower incidence of coronary heart disease compared with those in Western populations.35 Therefore, the nonlinear relation between HbA1c and stroke might be especially relevant to Asians."

While I hope this study is very valuable to Asian non-diabetic individuals with low HbA1c levels, I don’t feel that any of their conclusions are particularly relevant to me or my life. I do not think it was at all appropriate to extrapolate pieces of their conclusions to mean anything about people with D on this site.

While this may be a bit rude, I’m afraid that I would now have to individually look at every other study you’ve posted on this thread to be convinced that the results you’ve stated are actually the results of the study. I do not wish to spend my time doing that though.

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