Poster - #VH-79039 - Keywords: Hemoglobin A1c, Type 2 Diabetes, Hemoglbin, Hematocrit

Associations Between Elevated Red Blood Cell Parameters and Hemoglobin A1c Levels in Type II Diabetes.

J Gomez-Garcia,1 C Bi,2 and LV Rao1,3 1 UMass Chan Medical School, UMass Memorial Medical Center, Worcester, MA; 2 Quest Diagnostics, Secaucus, NJ; 3 Quest Diagnostics, Marlborough, MA
UMass Chan Medical School, UMass Memorial Medical Center, Worcester, MA Quest Diagnostics, Secaucus, NJ Quest Diagnostics, Marlborough, MA

ABSTRACT:
Type II diabetes is characterized by chronic hyperglycemia, and hemoglobin A1c (HbA1c) is a key biomarker for assessing long-term glycemic control. HbA1c reflects average blood glucose over the past 3 to 4 months and is widely used to diagnose and manage diabetes.1
However, HbA1c can be influenced by factors beyond glucose alone, particularly those affecting red blood cell (RBC) lifespan and characteristics.2 Variations in RBC parameters—including hemoglobin concentration (HgB), hematocrit (HCT), RBC count, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width (RDW)—may alter HbA1c levels independently of actual glycemic status.3
Medical conditions with increased RBC turnover result in falsely low HbA1c levels, underscoring the need to use alternative glycemic markers or adjusted HbA1c values to accurately reflect glycemic control in these patients.4,5 Conditions with decreased RBC turnover or increased HgB and HCT, such as erythrocytosis, polycythemia, and androgen replacement therapy may also affect HbA1c levels.6
To understand the effects of such conditions, this study investigated the relationship between RBC parameters and HbA1c levels in patients with type II diabetes.