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

Abstract

<p><strong>OBJECTIVE </strong></p> <p>To examine the role of glycemic measures performed during childhood in predicting future diabetes related nephropathy and retinopathy in a high-risk indigenous American cohort. </p> <p><em><strong>RESEARCH DESIGN AND METHODS</strong></em></p> <p>We studied associations between glycated hemoglobin (HbA1c) and 2-hour plasma glucose (2-hr PG), measured during childhood (5-<20 years) in a longitudinal observational study of diabetes and its complications (1965-2007) with 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 ROC curve (AUC) for childhood glycemic measures when predicting nephropathy and retinopathy were compared. </p> <p><strong>RESULTS</strong></p> <p>Higher baseline levels of HbA1c and 2-hr PG significantly increased risk of future severe albuminuria [(HbA1c: HR=1.45 per %, 95% CI: 1.02-2.05) and (2-hr PG: HR=1.21 per mmol/L, 95% CI: 1.16-1.27)]. When categorized by baseline HbA1c, children with prediabetes had higher incidence of albuminuria (29.7 cases/1,000 PY), severe albuminuria (3.8 cases/1,000 PY) and retinopathy (7.1 cases/1,000 PY) than children with normal HbA1c levels (albuminuria: 23.8 cases/1,000 PY; severe albuminuria: 2.4 cases/1,000 PY; retinopathy: 1.7 cases/1,000 PY); children with diabetes at baseline had the highest incidence of the three complications<em>.</em> No significant differences were observed between AUCs for models with HbA1c, 2-hr PG, and FPG when predicting albuminuria, severe albuminuria, or retinopathy.</p> <p><strong>CONCLUSIONS</strong></p> <p>In this study, higher glycemia levels ascertained by HbA1c and 2-hr PG during childhood were associated with future microvascular complications; this demonstrates potential utility of screening tests performed in high-risk children in predicting long-term health outcomes.</p>