Ethnicity Affects A1C Levels in Patients With Diagnosed Type 2 Diabetes in Southern Israel

Purpose To assess whether ethnicity affects the association between A1C and fasting glucose in people with type 2 diabetes. Methods An epidemiological, cross-sectional study based on computerized medical records of the Southern District of Clalit Health Services. The study population comprised patients ≥40 years of age with type 2 diabetes who underwent blood tests between 8 August 2015 and 20 July 2020. A normal-error multiple linear regression model was used to assess differences in associations among ethnic groups (i.e., Arabs, Ethiopian Jews, and non-Ethiopian Jews) and A1C. Results A total of 59,432 patients with type 2 diabetes were included in the study. Of these, 1,804 were Jews of Ethiopian origin, 49,296 were non-Ethiopian Jews, and 8,332 were Arabs. Compared with non-Ethiopian Jews, A1C levels were increased by 0.1% (1 mmol/mol) among Ethiopian Jews and by 0.3% (3 mmol/mol) among Arabs. Ethnicity was a strong predictor of A1C, explaining 0.6% of its variance. An A1C level of 7% (53 mmol/mol) correlated with fasting glucose levels of 141, 136, and 126 mg/dL in non-Ethiopian Jews, Ethiopian Jews, and Arabs, respectively. Conclusion Ethnic differences in A1C should be considered by clinicians, researchers, and policymakers.