1599-P: Glycated Albumin Identifies Dysglycemia Not Detected by A1C: The Case for Combining Glycated Albumin and A1C in Africans

Abstract

As the diabetes (DM) epidemic spreads in Africa, affected adults are younger and less obese than in high-income regions of the world. A1C, a nonfasting marker of glycemia, is used to diagnose dysglycemia, a summary term for prediabetes and DM. However, independent of glycemia, A1C increases with age and BMI. Conversely, hemoglobinopathies common in Africa such as sickle cell trait (SCT) can lead to artefactually low A1C levels. Because of the challenges surrounding A1C, attention is turning to glycated albumin (GA). Our goal was to determine in Africans the value of A1C and GA when a) performed individually and b) combined. OGTT was performed and A1C and GA levels were measured in 366 African-born blacks currently living in the Washington, DC area (male: 67%). Diagnosis of dysglycemia was based on fasting glucose≥100 mg/dL or 2h glucose≥140 mg/dL. The ability of A1C≥5.7% and GA≥14.2% to diagnose dysglycemia was evaluated. Both A1C≥5.7% and GA≥14.2% represent the upper quartile cut-off for their distribution in the population. To assess the value of performing both GA and A1C, people with dysglycemia were divided into 2 groups: 1) A1C-group detected by A1C only or A1C and GA; 2) GA-group identified by GA only and not detected by A1C. Dysglycemia occurred in 36% (135/366) of participants. SCT occurred in 17% (62/366) of the cohort and 20% (27/135) of people with dysglycemia. Sensitivities of A1C and GA were only 43% and 33%, resp. However, combining A1C and GA led to a sensitivity of 60% and this was better than either test alone (P<0.01). People identified by GA but not A1C were younger (age: 42±10 vs. 47±9y (mean±SD), P=0.05) and less obese (BMI: 26.7±2.5 vs. 30.3±4.5, P<0.01). A1C identified 52% (14/27) of the people with SCT and dysglycemia. GA identified an additional 22% (6/27) of people with SCT and dysglycemia not detected by A1C. Overall, combining GA with A1C leads to improved detection of dysglycemia in Africans from three groups: SCT, the nonobese and younger adults. Disclosure R. Mugeni: None. J.Y. Aduwo: None. S.M. Briker: None. M.F. Horlyck-Romanovsky: None. L. Mabundo: None. C. DuBose: None. A.E. Sumner: None.