Why Blood Test Numbers Can Trick the Diabetes Test
A-049 Associations Between Elevated Red Blood Cell Parameters and Hemoglobin A1c Levels in Type II Diabetes
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
RDW shows no significant correlation with A1c, despite theoretical reasons to expect one.
RDW is often considered a marker of red blood cell turnover and health, and abnormal RDW has been linked to inflammation and poor outcomes in diabetes. Many assume it would affect A1c accuracy, but this study found no link.
Practical Takeaways
If your A1c doesn’t match your glucose meter readings, ask your doctor to check your red blood cell parameters like hemoglobin, HCT, MCV, and MCHC.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
RDW shows no significant correlation with A1c, despite theoretical reasons to expect one.
RDW is often considered a marker of red blood cell turnover and health, and abnormal RDW has been linked to inflammation and poor outcomes in diabetes. Many assume it would affect A1c accuracy, but this study found no link.
Practical Takeaways
If your A1c doesn’t match your glucose meter readings, ask your doctor to check your red blood cell parameters like hemoglobin, HCT, MCV, and MCHC.
Publication
Journal
Clinical Chemistry
Year
2025
Authors
José L. Gómez-García, Caixia Bi, L. V. Rao
Related Content
Claims (4)
HbA1c might show high blood sugar even in people who actually have normal levels, because some people's red blood cells live longer than usual.
In people with type 2 diabetes, certain blood traits like red blood cell size and count might change A1c levels — not because of blood sugar, but because of how those cells are made. So, your A1c might look high or low even if your sugar control is fine.
Men and women with type 2 diabetes show similar links between blood cell traits and A1c levels, so doctors can use the same A1c rules to monitor both.
In people with type 2 diabetes, a blood test measure called RDW doesn’t seem to be linked to their average blood sugar levels (A1c), so it probably doesn’t affect how doctors read those A1c results.