Glycemic Measures in Childhood as Predictors of Future Diabetes-Related Microvascular Complications in an Indigenous American Population

OBJECTIVETo examine the role of glycemic measures performed during childhood in predicting future diabetes-related nephropathy and retinopathy in a high-risk indigenous American cohort.RESEARCH DESIGN AND METHODSWe studied associations between glycated hemoglobin (HbA(1c)) and 2-h plasma glucose (PG), measured during childhood (age 5 to <20 years) in a longitudinal observational study of diabetes and its complications (1965-2007), and future albuminuria (albumin creatinine ratio [ACR] >= 30 mg/g), severe albuminuria (ACR >= 300 mg/g), and retinopathy (at least one microaneurysm or hemorrhage or proliferative retinopathy on direct ophthalmoscopy). Areas under the receiver operating characteristic curve (AUCs) for childhood glycemic measures when predicting nephropathy and retinopathy were compared.RESULTSHigher baseline levels of HbA1c and 2-h PG significantly increased the risk of future severe albuminuria (HbA(1c): hazard ratio [HR] 1.45 per %; 95% CI 1.02-2.05 and 2-h PG: HR 1.21 per mmol/L; 95% CI 1.16-1.27). When categorized by baseline HbA(1c), children with prediabetes had a higher incidence of albuminuria (29.7 cases per 1,000 person-years [PY]), severe albuminuria (3.8 cases per 1,000 PY), and retinopathy (7.1 cases per 1,000 PY) than children with normal HbA(1c) levels (23.8, 2.4, and 1.7 cases per 1,000 PY, respectively); children with diabetes at baseline had the highest incidence of the three complications. No significant differences were observed between AUCs for models with HbA(1c), 2-h PG, and fasting PG when predicting albuminuria, severe albuminuria, or retinopathy.CONCLUSIONSIn this study, higher glycemia levels ascertained by HbA(1c) and 2-h PG during childhood were associated with future microvascular complications; this demonstrates the potential utility of screening tests performed in high-risk children in predicting long-term health outcomes.