Transition of care from pre-dialysis prelude to renal replacement therapy: the blueprints of emerging research in advanced chronic kidney disease

Abstract

In patients with advanced (estimated glomerular filtration rate <25 mL/min/1.73 m2) non-dialysis-dependent chronic kidney disease (CKD) the optimal transition of care to renal replacement therapy (RRT), i.e. dialysis or transplantation, is not known. Mortality and hospitalization risk are extremely high upon transition and in the first months following the transition to dialysis. Major knowledge gaps persist pertaining to differential or individualized transitions across different demographics and clinical measures during the 'prelude' period prior to the transition, particularly in several key areas: (i) the best timing for RRT transition; (ii) the optimal RRT type (dialysis versus transplant), and in the case of dialysis, the best modality (hemodialysis versus peritoneal dialysis), format (in-center versus home), frequency (infrequent versus thrice-weekly versus more frequent) and vascular access preparation; (iii) the post-RRT impact of pre-RRT prelude conditions and events such as blood pressure and glycemic control, acute kidney injury episodes, and management of CKD-specific conditions such as anemia and mineral disorders; and (iv) the impact of the above prelude conditions on end-of-life care and RRT decision-making versus conservative management of CKD. Given the enormous changes occurring in the global CKD healthcare landscape, as well as the high costs of transitioning to dialysis therapy with persistently poor outcomes, there is an urgent need to answer these important questions. This review describes the key concepts and questions related to the emerging field of 'Transition of Care in CKD', systematically defines six main categories of CKD transition, and reviews approaches to data linkage and novel prelude analyses along with clinical applications of these studies.

Keywords: advanced chronic kidney disease; prelude; renal replacement therapy; transition; vintage.

FIGURE 1:

Higher mortality during the first several months of transition to maintenance dialysis therapy, reflected by the crude annualized mortality rates over the first 24 months after transition to maintenance dialysis treatment, stratified by dialysis provider, in 52 172 incident ESRD veterans from October 2007 to September 2011. The dialysis providers include the two major large dialysis organizations (Fresenius Medical Care and DaVita), other dialysis chains, independent dialysis centers (non-chains) and dialysis centers that are based in a Veterans Affairs (VA) medical center (adapted from the USRDS 2015 Annual Data Report, chapter on Transition of Care in CKD, Veterans Data, www.USRDS.org) [1].

FIGURE 2:

Common scenarios of transitions of care in patients with an advanced CKD (eGFR <25 mL/min/1.73 m² body surface area) to RRT, and potential challenges and pitfalls of examining these transitions in epidemiologic studies (see also Table 1 for different types of transition). HD, hemodialysis; PD, peritoneal dialysis.

FIGURE 3:

Schematic illustrations of the concepts of ‘prelude’ and ‘vintage’ periods in examining the transition of care from advanced CKD (eGFR <25 mL/min/1.73 m² body surface area) to renal replacement therapy, along with the trends in residual kidney function (eGFR) (solid line) and variations in patient mortality (vertical bars) and costs of CKD patient care (dotted line) at different points in time relative to the transition intercept.