New-Onset Diabetes After Renal Transplantation

New-onset diabetes after transplantation (NODAT) is a serious and frequent metabolic complication after renal transplantation. This entity is currently well defined since the publication of the International Consensus Guidelines in 2003. Here, we review the factors contributing to the risk of NODAT and the strategies related to modifiable factors, with emphasis on practical issues. Recognizing these factors may help clinicians to evaluate prospectively appropriate prevention strategies to minimize the risk of NODAT. Over the past 50 years, the concept of NODAT has evolved in terms of name and definition. Before 2003, de novo diabetes that developed after transplantation was described in various terms, most frequently “posttransplantation diabetes mellitus,” and suffered from a lack of consensus regarding its definition. The most commonly used clinical definition was the requirement of insulin for a minimum period posttransplantation (often 30 days). This definition, however, identified only the most severe cases, leaving out the majority of patients with glucose metabolism disorders. International Consensus Guidelines on NODAT were published in 2003. They recommended that the diagnosis of NODAT should be based on the American Diabetes Association (ADA) criteria for type 2 diabetes published in 2003 (1,2). Since then, a follow-up report from the International Expert Committee further lowered the inferior limit of fasting plasma glucose (FPG) (100 mg/dL) that corresponds to impaired fasting glucose (IFG), based on epidemiologic predictive data (3). In addition, since 2009, the International Expert Committee recommended the use of a standardized A1C assay for diabetes diagnosis (A1C level ≥6.5%), a position that has been endorsed by ADA in 2010 (4). The Expert Committee stated that A1C assay cannot be used in conditions that change red cell turnover. This is the case of end-stage renal disease (ESRD) patients and newly transplanted kidney patients. For instance, the posttransplant period is frequently associated …