Differences in participant classification and intervention effects based on HbA1C and fasting plasma glucose among a community sample of African Americans

Since 2010, the American Diabetes Association has endorsed both HbA1C (A1C) and fasting plasma glucose (FPG) to determine diabetes risk. Given the discordance between classifications based on FPG and A1C and higher A1C levels among African Americans (AAs) than whites, we sought to examine the prevalence of normoglycemia, prediabetes, and diabetes among a community sample of adult AAs (n=704) screened for enrollment in a randomized Diabetes Prevention Program (DPP). We conducted a retrospective analysis to estimate the degree of discordance between risk categories based on FPG and A1C and examine the risk factors that predicted A1C and FPG levels. To determine differential effects on risk categories defined using FPG and A1C, we examined the effects of the program on the measures at 12 weeks post-intervention among the intervention arm participants.