Inverse association between glycated albumin and insulin secretory function may explain higher levels of glycated albumin in subjects with longer duration of diabetes.

BACKGROUND:Glycated albumin (GA) has been increasingly used as a reliable index for short-term glycemic monitoring, and is inversely associated with β-cell function. Because the pathophysiologic nature of type 2 diabetes (T2D) is characterized by progressive decline in insulin secretion, the aim was to determine whether GA levels were affected by diabetes duration in subjects with T2D. METHODS:To minimize the effect of glucose variability on GA, subjects with stably maintained HbA1c levels of <0.5% fluctuation across 6 months of measurements were included. Patients with newly diagnosed T2D (n = 1059) and with duration>1 year (n = 781) were recruited and categorized as New-T2D and Old-T2D, respectively. Biochemical, glycemic, and C-peptide parameters were measured. RESULTS:GA levels were significantly elevated in HbA1c-matched Old-T2D subjects compared to New-T2D subjects. Duration of diabetes was positively correlated with GA, whereas a negative relationship was found with C-peptide increment (ΔC-peptide). Among insulin secretory indices, dynamic parameters such as ΔC-peptide were inversely related to GA (r = -0.42, p<0.001). Multiple linear regression analyses showed that duration of diabetes was associated with GA (standardized β coefficient [STDβ] = 0.05, p<0.001), but not with HbA1c (STDβ = 0.04, p