The causes of mortality in kidney transplant patients and the risk factors for mortality have been widely published. However, there is a high variability according to geographical areas and time. Recent studies suggest that the classical hierarchy of causes of mortality, i.e. the predominance of cardiovascular causes of death, could be overturned by the increase in infectious and cancer-related deaths. Investigators will try to highlight this paradigm shift and the related risk factors by studying two large French transplantation databases.