OBJECTIVES:  A major challenge in the field of renal transplantation is to prolong patient survival.  Previous studies have demonstrated that renal function at 1 year is a major determinant of long term patient survival.  Furthermore, the development of new onset diabetes after transplantation identifies patients at high risk of cardiovascular events and mortality. This study aims to quantify any additive effect of impaired renal function and elevated glucose levels at 1 year post transplant on patient mortality. METHODS: Consecutive renal transplants from a single UK transplant centre over a 10 year period were analysed using multivariate logistic regression in SPlus 8; the risk of patient mortality was assessed after stratification by renal function (measured by glomerular filtration rate (GFR)) and impaired fasting glucose levels. RESULTS: Data were available on 307 patients with fasting glucose and GFR measurements at 1 year post transplant.  Overall 37% (n=114) had a GFR of less than 40mL/minute and of these, 24% (n=27) had fasting glucose levels greater than 7 mmol/L.  After adjusting for age, sex and donor factors patients with fasting glucose greater than 7 mmol/L and a GFR less than 40mL/minute had a mortality odds ratio of 5.47 (p<0.01) compared to those with glucose levels less than 5.6 mmol/l and a GFR greater than 40 mL/minute. CONCLUSIONS: This study demonstrates that the development of impaired fasting glucose post transplants is associated with a 35% increase risk of mortality and the development of new onset diabetes associated with a 2-fold increased risk.  Our study further suggests that there is a negative synergistic effect of deteriorating renal function and progressive impaired glucose regulations on patient survival. Consequently,  therapeutic strategies that could both improve GFR at one year and the incidence of diabetes might be expected to improve long term patient survival.