Cardiovascular Risk Profile in Subjects With Prediabetes and New-Onset Type 2 Diabetes Identified by HbA1c According to American Diabetes Association Criteria

Abstract

OBJECTIVE We investigated the cardiovascular risk profile in subjects with prediabetes and new-onset type 2 diabetes identified by glycated hemoglobin A1c (HbA1c) according to the new American Diabetes Association criteria. RESEARCH DESIGN AND METHODS Arterial stiffness, intima-media thickness (IMT), soluble receptor for advanced glycation end products (sRAGEs), and oral glucose tolerance test (OGTT) were evaluated in 274 subjects without a previous history of diabetes. The subjects were stratified into three groups according to the HbA1c levels. RESULTS The subjects with prediabetes (n = 117, HbA1c 5.7–6.4% [39–46 mmol/mol]) showed a higher augmentation (Aug), augmentation index (AugI), and IMT compared with those with lower HbA1c; however, these values were similar to those of subjects with HbA1c >6.5% (48 mmol/mol). When we further analyzed the subjects with prediabetes but included only subjects with normal glucose tolerance (NT) in the analysis, AugI and IMT still remained significantly higher than their levels in control subjects with HbA1c <5.7% (39 mmol/mol). After multiple regression analyses including several cardiovascular risk factors, only HbA1c, age, and sRAGE were significantly correlated with the IMT, whereas age and 1-h postload glucose were the major determinants of AugI. CONCLUSIONS Our data show that subjects with prediabetes according to HbA1c, but with both NT according to the OGTT and normal fasting glycemia, have an altered IMT and AugI. These data suggest that a simple, reproducible, and less expensive marker such as HbA1c may be better able to identify prediabetic subjects at high cardiovascular risk compared with fasting glycemia or OGTT alone.