New-onset diabetes after transplantation

Abstract

New-onset diabetes after transplantation (NODAT) is a common and clinically important complication of solid-organ transplantation. Consensus guidelines have recently been published with the aim of increasing awareness of NODAT among the transplant and diabetes communities. Current evidence suggests that the development of post-transplant diabetes has adverse effects on recipient and graft survival. While the pathogenesis of NODAT remains incompletely understood, insulin resistance and insulin deficiency have been identified as key metabolic abnormalities. These defects may be aggravated by certain classes of immunosuppressive drugs, notably corticosteroids and the immunophilins, tacrolimus and ciclosporin. The incidence and prevalence of NODAT, and lesser degrees of glucose intolerance which may also be clinically relevant, were almost certainly underestimated in many early studies. The consensus guidelines call for abandonment of arbitrary diagnostic criteria in favour of current internationally accepted definitions for diabetes and states of glucose intolerance. Recent demographic trends warn of an increasing threat from NODAT: the age of transplant recipients is rising and this population has become more obese. With risk factors for NODAT now identified (older age, obesity, non-white ethnicity, family history of diabetes and hepatitis C infection), it may be possible to reduce the incidence in susceptible individuals listed for transplantation. Lifestyle measures directed at controlling body weight - before and after transplantation - allied to tailored immunosuppressive therapy are recommended. However, since the efficacy and safety of these measures have not been rigorously evaluated in clinical trials, many uncertainties remain. Oral antidiabetic agents and/or insulin treatment are required in a proportion of patients, sometimes temporarily. In addition to the risks of atherothrombotic cardiovascular disease, patients with irreversible NODAT should be considered to be at risk of long-term microvascular complications including retinopathy, foot disease and nephropathy. Further studies are required to ascertain the current incidence, prevalence and natural history NODAT in order to identify more effective strategies for prevention and management. Copyright © 2006 John Wiley & Sons, Ltd.