Abstract P331: Ethnic Differences in Glycoslation Indices in Non-Diabetic Adults: The Diabetes, Heart and Health Survey

Abstract

Objective: We examined whether there were ethnic differences in glycosylated haemoglobin concentrations, the glycation gap and haemoglobin glycation index in non-diabetic adults. Research design and methods: We studied 3,318 non-diabetic adults aged 35 to 74 years. Glycoslylated haemoglobin (HbA1c) levels were compared in 1,589 Europeans, 825 Maori, 689 Pacific and 226 Asians. The glycation gap was calculated using the residuals from the regression of HbA1c on mean fasting and 2 hour glucose levels and the haemoglobin glycation index using the residuals from the regression of HbA1c on fructosamine. Results: Mean ± SD HbA1c was 38.0 ± 4.57 mmol/mol. After adjusting for age and gender, mean (se) HbA1c was higher in Maori (38.6 mmol/mol (0.14)), Pacific (40.8 (0.16)) and Asians (37.9 (0.27)) compared with Europeans (36.5 (0.10)) (all P &lt 0.0001 vs. Europeans). In contrast, there was little difference in fructosamine levels between ethnic groups with 231.5 (0.63) μmol/L in Europeans, 230.7 (0.44) in Maori, 237.8 (1.16) in Asians (both P &gt 0.05 versus Europeans), and 232.7 (0.16) in Pacific (P &lt 0.05). After adjusting for age, sex, education, body mass index (BMI), systolic and diastolic blood pressure, fasting and post-glucose load glucose levels, cholesterol, triglycerides, HDL-cholesterol, physical exercise levels, total calorie intake and socioeconomic status, HbA1c levels were 37.0 (0.10) mmol/mol in Europeans, and remained higher in Maori (38.4 (0.13)), Pacific (40.0 (0.15)) and Asians (38.1 (0.25)) (all P &lt 0.001) compared to Europeans. The mean (se) age and gender adjusted glycation gap (based on fructosamine) was -1.50 (0.10) mmol/mol for Europeans, 0.66 (0.14) mmol/mol for Maori, 2.77 (0.16) mmol/mol for Pacific (Both (P &lt 0.0001 vs. Europeans), and -0.37 (0.27) mmol/mol in Asians (P =0.001 vs. Europeans. Similarly, the mean haemoglobin glycation index (based on mean glucose) was -1.34 (0.10) in Europeans, 0.41 (0.13) in Maori, 2.63 (0.15) in Pacific (both P &lt 0.0001 versus Europeans) and -0.45 (0.25) in Asians (P = 0.001 vs. Europeans). Conclusion: There were differences in HbA1c, the glycation gap and the haemoglobin glycation index between Europeans and Maori, Pacific and Asian non-diabetic adults, but there was little difference between ethnic groups for fructosamine. These differences could be due to heritable factors that may vary between the ethnic groups or may be related to high or low glycators.