Pragmatic Trial of Higher vs. Lower Serum Phosphate Targets in Patients Undergoing Hemodialysis (HiLo)

May 2021 Council

Lead Division/Office

KUH

Point(s) of Contact

Executive Summary

Current clinical practice guidelines recommend lowering phosphate levels to the normal range in dialysis patients to mitigate morbidity and mortality from coronary calcification, however, we have no randomized controlled data to justify this practice. HiLo is the first trial that will randomize 4396 hemodialysis patients to a (1) Hi group: where dieticians will treat to target a phosphate level ≥6.5 mg/dL OR (2) a low group: where the target phosphate will be < 5.5 mg/dL. The primary outcome is a composite hierarchal outcome of all-cause mortality and hospitalization. Study hypothesis: participants randomized to a phosphate target of ≥6.5 mg/dL will be less likely to reach the composite outcome than participants targeted to <5.5 mg/dL.  PI Wolf is currently funded through a Collaboratory project under a UH3 mechanism until 2023. Study initiation was slowed because of its complex multisite nature, implementation of novel statistical methods, and the impact of COVID 19 on clinical trial activities. The clinical question remains relevant and the DSMB recommend study continuation. We recommend an additional two years of support for this trial so it can complete enrollment, answer relevant questions of high importance to hemodialysis patients, and be published in a high-level clinical journal to reach the widest possible audience.