The Authors' Reply: HbA1c Is Insensitive at Month 3 After Kidney Transplantation.

Abstract

We thank Chadban and colleagues1 for their interest in our article2 and effort that confirms a low sensitivity of HbA1c for detection of posttransplant diabetes mellitus (PTDM) in the early phase after renal transplantation. They find similar results in a cohort with a higher exposure of calcineurin inhibitors and steroids. We agree with their insightful comments on temporal changes in the performance of HbA1c in diagnosing PTDM. In our study, we assessed the utility of HbA1c for detection of PTDM by the standard diagnostic criteria. The purpose of screening for diabetes after transplantation is to detect patients at risk of diabetic complications. The introduction of HbA1c as a diagnostic criterion for type 2 diabetes mellitus was based on associations with microvascular complications.3 However, in the transplant setting, we are more concerned with macrovascular complications.4,5 Therefore, studies that estimate associations between overall and cardiovascular morbidity and mortality and the standard and proposed diagnostic criteria for PTDM are warranted.