Combining A1C with Glycated Albumin Improves Detection of Abnormal Glucose Tolerance in Nonobese Africans—The Africans in America Study

As diabetes prevalence rises in Africa, tests to detect abnormal glucose tolerance (abnl-GT) must be optimized. Recent reports suggest A1C performs well as a diagnostic test for abnl-GT in the OB. In contrast, glycated albumin (GA) contributes to the detection of abnl-GT in the nonobese. To determine if BMI affects sensitivity of A1C and GA in Africans, we evaluated the sensitivity of A1C and GA separately and combined to detect abnl-GT in 88 OB blacks (age 42±10y, BMI 33.4±2.9, range 30.0-42.4) and 232 nonobese blacks (age 38±10y, BMI 25.5±2.6, range 18.2-29.8) who were born in Africa and live in the U.S.A. Abnl-GT was determined by glucose criteria for the OGTT. Thresholds for A1C and GA were defined by the cut-off at their upper quartile (A1C≥5.7%; GA ≥13.97%). Prevalence of abnl-GT in OB and nonobese Africans were: 43% v 35%, P=0.20, resp. In the OB, sensitivities of A1C, GA and the combined tests were: 67%, 29% and 79% resp (Figure A). In the OB, sensitivity of A1C + GA was similar to A1C alone (P=0.13). For the nonobese, sensitivities of A1C, GA and the combined tests were: 35%, 38% and 62% resp (Figure B). Sensitivity increased when the tests were combined because abnl-GT was detected in 22 nonobese Africans not identified by A1C. Patterns were similar by sex and region of Africa. Data from Africans living in the U.S.A suggest detection of abnl-GT in the nonobese is improved by combining A1C with GA. Disclosure J. Kabakambira: None. S.M. Briker: None. R.L. Baker: None. C. DuBose: None. L. Mabundo: None. S.T. Chung: None. D.B. Sacks: Other Relationship; Self; Sebia, Trinity Biotech. A.E. Sumner: None.