Glycated albumin as a diagnostic tool in diabetes: An alternative or an additional test?

INTRODUCTION: Studies have revealed that glycated albumin (GA) is a useful alternative to HbA(1c) under conditions wherein the latter does not reflect glycaemic status accurately. Until now, there are few studies with non-Asians subjects that report on the validity of GA test in diagnosis of type 2 diabetes mellitus (DM). Thus, the aim of this study was to assess the clinical utility of GA in diagnosis of DM. MATERIALS AND METHODS: This diagnostic test accuracy study was performed in 242 Brazilian individuals referred for OGTT in a tertiary university hospital. ROC curves were used to access the performance of GA and HbA(1c) in the diagnosis of DM by oral glucose tolerance test (OGTT). RESULTS: OGTT, HbA(1c) and GA were performed in all 242 participants (40.5% male, age 54.4 ± 13.0 years [mean ± SD], body mass index 28.9 ± 6.3 kg/m(2)). DM by OGTT was detected in 31.8% of individuals. The equilibrium threshold value of GA ≥14.8% showed sensitivity of 64.9% and specificity of 65.5% for the diagnosis of DM. The AUC for GA [0.703 (95% CI 0.631–0.775)] was lower than for HbA(1c) [0.802 (95% CI 0.740–0.864)], p = 0.028. A GA value of 16.8% had similar accuracy for detecting DM as defined by HbA(1c) ≥6.5% (48 mmol/mol) with sensitivity of 31.2% and specificity of 93.3% for both tests. However, GA detects different subjects from those detected by HbA(1c) and OGTT. CONCLUSIONS: GA detected different individuals with DM from those detected by HbA(1c), though it showed overall diagnostic accuracy similar to HbA(1c) in the diagnosis of DM. Therefore, GA should be used as an additional test rather than an alternative to HbA(1c) or OGTT and its use as the sole DM diagnostic test should be interpreted with caution.