Relationship Between Fasting Plasma Glucose and Hemoglobin A1c by Race

Open Access
Healy, Michael
Area of Honors:
Bachelor of Science
Document Type:
Thesis Supervisors:
  • Christopher Michael Bopp, Thesis Supervisor
  • Mary Jane De Souza, Honors Advisor
  • glucose
  • Hemoglobin A1c
  • diabetes
  • prediabetes
Current understanding of the relationship between fasting plasma glucose (FPG) and Hemoglobin A1c (HbA1c) may no longer be accurate. A variety of genetic, environmental and lifestyle factors help point to the complexity of the relationship. This experiment tests the linearity observed between FPG and HbA1c values measured amongst different self-reported races of men and women in the Pennsylvania State University undergraduate and graduate student population (Age = 21.21 ± 1.86 years). Experimental testing was completed using finger-stick screening with lipid-glucose and HbA1c tests on students fasted for a minimum of 9-12 hours before blood sampling. Results of (n=217) subjects (n=117 Non-Hispanic White race, n=100 Other Races) revealed significant differences in HbA1c values of 0.28% between the Non-Hispanic White race versus Other Races using the A1cNow+ System (PTS Diagnostics, Indianapolis, IN) (p < 0.00003) and difference in 0.15% between the Non-Hispanic White race versus Other Races using the DCA Vantage Analyzer (Siemens Medical Solutions USA, Inc.) (p < 0.007). Additionally, no statistically significant correlations between FPG and either HbA1c measurement used were found, demonstrating a non-linear relationship between the two variables in the entire sample population, and once again when analyzed in the Non-Hispanic White race and Other Races categories specifically. The findings described have clinical significance in evaluating the relationship between HbA1c and FPG, and using HbA1c as part of the diagnostic criteria for prediabetes and diabetes.