Defining end-stage renal disease in clinical trials: a framework for adjudication

Unlike definition of stroke and myocardial infarction, there is no uniformly agreed upon definition to adjudicate end-stage renal disease (ESRD). ESRD remains the most unambiguous and clinically relevant end point for clinical trialists, regulators, payers and patients with chronic kidney disease. The prescription of dialysis to patients with advanced chronic kidney disease is subjective and great variations exist among physicians and countries. Given the difficulties in diagnosing ESRD, the presence of estimated GFR <15 mL/min/1.7 3m(2) itself has been suggested as an end point. However, this definition is still a surrogate since many patients may live years without being symptomatic or needing dialysis. The purpose of this report is to describe a framework to define when the kidney function ends and when ESRD can be adjudicated. Discussed in this report are (i) the importance of diagnosing symptomatic uremia or advanced asymptomatic uremia thus establishing the need for dialysis; (ii) establishing the chronicity of dialysis so as to distinguish it from acute dialysis; (iii) establishing ESRD when dialysis is unavailable, refused or considered futile and (iv) the adjudication process. Several challenges and ambiguities that emerge in clinical trials and their possible solutions are provided. The criteria proposed herein may help to standardize the definition of ESRD and reduce the variability in adjudicating the most important renal end point in clinical trials of chronic kidney disease.