Negative outcome studies in end-stage renal disease: how dark are the storm clouds?

Abstract

The end-stage renal disease (ESRD) population treated by dialysis has grown remorselessly over the last five decades, in all continents. This growth is already a major burden to the healthcare economies of wealthy countries, and is thus a challenge for policy makers, health care providers and financial planners [1]. Fortunately, recent data (just published in NDT) suggest a stabilization/decline in the incidence of ESRD in some developed countries, possibly related to the successful implementation of renoprotective strategies in pre-dialysis chronic kidney disease (CKD) [2,3]. Dialysis patients have an impressive and worrying mortality, comparable to or worse than that seen in many cancers, e.g. 20–25% annualized mortality in some systems [4]. Around 50% of this increased mortality is due to cardiovascular (CV) disease. This is explicable, as at the start of dialysis, up to 80% of subjects already have at least subclinical CV disease. Despite significant progress in many branches of medicine over the last decades—for example, significant reductions in myocardial infarction and stroke rates in the general population [5,6]—mortality rates for dialysis patients remain practically unchanged [4,7] over the same time period. This is first explained by more liberal criteria for inclusion in renal replacement therapy (RRT) programmes, with more elderly, diabetic and CV-diseased patients treated by dialysis in recent years. Second, CV disease in ESRD is often underinvestigated and undertreated, compared to CV disease in non-renal cohorts [8]. Third, therapeutic interventions in dialysis patients aimed at reducing CV morbidity and mortality may be either ‘too little, too late’ or inadequate, as most traditional and uraemia-specific [9] risk