Association between Glycosylated Haemoglobin Level and Contrast-Induced Acute Kidney Injury in Patients with Type 2 Diabetes Mellitus

Abstract

Background: There are several reports suggesting that admission hyperglycaemia increases the risk of contrast-induced acute kidney injury (CI-AKI). However, it is not clear whether there has been an association between long-standing poor glycaemic control and the incidence of CI-AKI. The purpose of this study was to examine the impact of poor glycaemic control or elevated glycosylated haemoglobin (HbA1c) on the incidence of CI-AKI in patients with type 2 diabetes mellitus (T2DM). Methods: The present study prospectively enrolled 133 patients with T2DM undergoing elective coronary angiography (CAG) and/or intervention. All patients had an estimated glomerular filtration rate (eGFR) of ≥60 ml/min/1.73 m². Patients were divided into two groups: those with an optimal HbA1c (<7%) and those with an elevated HbA1c (≥7%). All had similar baseline characteristics and were hydrated appropriately. The outcome was assessed by the incidence of CI-AKI. Results: CI-AKI occurred in 2 of 41 patients (4.9%) with optimal HbA1c levels and 5 of 92 patients (5.4%) with elevated HbA1c levels (p = 0.89). The cutoff point of HbA1c was set at 6.5%, but no statistically significant difference between the two groups was observed [1 of 24 patients (4.1%) vs. 6 of 109 patients (5.5%), p = 0.79]. However, despite a high variability in the incidence of CI-AKI, there was no statistically significant difference between the two groups when varying CI-AKI definitions were considered. Conclusion: An elevated HbA1c level is not associated with a higher incidence of CI-AKI compared to optimal HbA1c levels in patients with T2DM (patients with an eGFR of ≥60 ml/min/1.73 m²) undergoing CAG and/or intervention.