Hemoglobin A1c and Fructosamine Evaluated in Patients with Type 2 Diabetes Receiving Peritoneal Dialysis Using Long-Term Continuous Glucose Monitoring

Abstract

<b><i>Introduction:</i></b> Shortened erythrocyte life span and erythropoietin-stimulating agents may affect hemoglobin A_1c (HbA_1c) levels in patients receiving peritoneal dialysis (PD). We compared HbA_1c with interstitial glucose measured by continuous glucose monitoring (CGM) in patients with type 2 diabetes receiving PD. <b><i>Methods:</i></b> Fourteen days of CGM (Ipro2, Medtronic) were performed in 23 patients with type 2 diabetes receiving PD and in 23 controls with type 2 diabetes and an estimated glomerular filtration rate over 60 mL/min/1.73 m². Patients were matched on gender and age (±5 years). HbA_1c (mmol/mol), its derived estimate of mean plasma glucose (eMPG_A1c) (mmol/L), and fructosamine (µmol/L) were measured at the end of the CGM period and compared with the mean sensor glucose (mmol/L) from CGM. <b><i>Results:</i></b> In the PD group, mean sensor glucose was 0.98 (95% con­fidence interval (CI): 0.43–1.54) mmol/L higher than the eMPG_A1c compared with the control group (<i>p</i> = 0.002) where glucose levels were nearly identical (−0.05 (95% CI: −0.35–0.25) mmol/L). A significant association was found between fructosamine and mean sensor glucose using linear regression with no difference between slopes (<i>p</i> = 0.89) or y-intercepts (<i>p</i> = 0.28). <b><i>Discussion/Conclusion:</i></b> HbA_1c underestimates mean plasma glucose levels in patients with type 2 diabetes receiving PD. However, the clinical significance of this finding is undetermined. Fructosamine seems to more accurately reflect glycemic status. CGM or fructosamine could complement HbA_1c to increase the accuracy of glycemic monitoring in the PD population.