PROJECT SUMMARY The risk of developing prediabetes and diabetes mellitus is higher among persons living with HIV (PLHIV). It has been estimated that about 50% of prevalent cases of diabetes mellitus, and an even higher level for prediabetes, remain undiagnosed particularly in low- and middle-income countries (LMICs). Empirical evidence suggests that over-reliance on glucose measures may be partly responsible for the poor diagnosis. The World Health Organization (WHO) and the International Federation of Diabetes (IDF) have included the glycosylated hemoglobin (HbA1c) test in their recommendations for diagnosis and monitoring of diabetes mellitus. The HbA1c test is considered highly valuable for early detection of diabetes and is becoming widely adopted in clinical practice including in LMICs. However, the HbA1c test is currently not recommended for use among PLHIV due to unreliable results attributable to the lower hemoglobin levels in this population. The major goal of the proposed study is to identify appropriate HbA1c diagnostic thresholds for strata of hemoglobin levels and markers of inflammation, insulin resistance and immuno-virologic status. Fructosamine, an alternative glycated test, which has no hemoglobin limitation, will also be evaluated. This will be accomplished through the following specific aims: Aim 1: Utilize hemogram and other biomarker stratifications to determine optimal HbA1c diagnostic thresholds for diabetes mellitus and prediabetes among persons living with and without HIV. Aim 2: Determine optimal fructosamine diagnostic thresholds for diabetes mellitus and prediabetes among persons living with and without HIV. Aim 3: Examine the diagnostic accuracy of combining HbA1c with fructosamine tests for the assessment of dysglycemia and develop an algorithm to guide testing based on biomarker levels. A multidisciplinary team of researchers has been assembled for this project, comprising internationally recognized experts in HIV, non-communicable diseases, diabetology/endocrinology, clinical chemistry, and infectious disease epidemiology from the University of Maryland, Institute of Human Virology Nigeria (IHVN) and local researchers from affiliate academic and clinical centers. We are employing a cross- sectional design to recruit 992 PLHIV along with age- and sex-matched 770 persons without HIV at the University of Abuja Teaching Hospital, a collaborating partner of IHVN. A comprehensive questionnaire with relevant components of the WHO stepwise approach instrument (STEPS) will be administered. Blood samples will be collected for HbA1c and fructosamine tests along with oral glucose tolerance test (OGTT) and relevant biomarkers (hemoglobin, serum proteins, c-reactive protein, insulin, CD4 count, HIV RNA). Results of HbA1c, fructosamine and OGTT, with the latter as gold standard, will be used to generate receiver operating characteristic (ROC) curves to determine optimal cut-offs based on biomarker strata. This project will resul...