Protocol for a prospective, cluster randomized trial to evaluate routine and deferred dialysis initiation (RADDI) in...

The timing of when to initiate dialysis for progressive chronic kidney disease (CKD) patients has not been well established. There has been a strong trend for early dialysis initiation for these patients over the past decades. However, the perceived survival advantage of early dialysis has been questioned by a series of recent observational studies. The only randomized controlled trial (RCT) research on this issue found the all-cause mortality, comorbidities, and quality of life showed no difference between early and late dialysis starters. To better understand optimal timing for dialysis initiation, our research will evaluate the efficacy and safety of deferred dialysis initiation in a large Chinese population.

The trial adopts a multicenter, cluster randomized, single-blind (outcomes assessor), and endpoint-driven design. Eligible participants are 18-80 years old, in stable CKD stages 4-5 (eGFR > 7 ml/min /1.73 m²), and with good heart function (NYHA grade I or II). Participants will be randomized into a routine or deferred dialysis group. The reference eGFR at initiating dialysis for asymptomatic patients is 7 ml/min /1.73 m² (routine dialysis group) and 5 ml/min/1.73 m² or less (deferred dialysis group) in each group. The primary endpoint will be the difference of all-cause mortality and acute nonfatal cerebro-cardiovascular events between the two groups. The secondary outcomes include hospitalization rate and other safety indices. The primary and secondary outcomes will be analyzed by appropriate statistical methods.

This study protocol represents a large, cluster randomized study evaluating deferred and routine dialysis intervention for an advanced CKD population. The reference eGFR to initiate dialysis for both treatment groups is targeted at less than 7 ml/min/1.73m². With this design, we aim to eliminate lead-time and survivor bias and avoid selection bias and confounding factors. We acknowledge that the study has limitations. Even so, given the low-targeted eGFR values of both arms, this study still has potential economic, health, and scientific implications. This research is unique in that such a low targeted eGFR value has never been studied in a clinical trial.

The trial has been approved by ClinicalTrials.gov (Trial registration ID NCT02423655). The date of registration was April 22, 2015.