Possible clinical effects of molecular hydrogen (H₂) delivery during hemodialysis in chronic dialysis patients: Interim analysis in a 12 month observation
Nakayama M, Itami N, Suzuki H, et al. · PLOS ONE. 2017;12(9):e0184535.
What kind of evidence is this?
Human
Prospective multicenter non-randomized observational comparison; prespecified 12-month interim analysis
Kidney and urinary health
Other forms
Not reported in this record.
Not reported in this record.
Methods at a glance
Adults receiving maintenance hemodialysis at seven Japanese dialysis centers.
308 were registered; 262 selected participants with complete 12-month data and no hospitalization, new cancer or death were analyzed: E-HD n=140 and conventional HD n=122.
12 months; this publication is an interim analysis of the longer registered cohort.
Electrolyzed-water hemodialysis three times weekly, generally 4–5 hours/session, using dialysate containing dissolved molecular H₂.
H₂ dissolved in dialysate — not inhaled, not swallowed and not Brown's gas.
Dialysate H₂ concentration varied from 30 to 80 ppb; reported blood flow was 200 mL/min and dialysate flow 500 mL/min.
Not applicable — H₂ was dissolved in dialysate rather than delivered as inhaled gas.
No O₂ was co-delivered as a distinct intervention.
Conventional hemodialysis at participating centers; treatment allocation was not randomized and treatment type was largely center-dependent.
Outcomes and reported result
Dialysis and laboratory parameters, antihypertensive drug dose, self-reported fatigue and pruritus and multivariable associations.
No clinically relevant group differences were found for dialysis-related parameters. Antihypertensive use and severe fatigue/pruritus were less frequent in E-HD in adjusted observational analyses, but the design cannot establish that H₂ caused those differences.
The complete PLOS ONE/PMC article, protocol, cohort selection, laboratory and symptom tables, funding and competing-interest disclosure were checked; the broad null dialysis findings and favorable adjusted associations are both represented.
A reported association, difference or mechanism is not automatically a clinical benefit. Null findings, outcome type, study design and precision all matter.
Cautions and applicability
Non-randomized center-based comparison, important baseline differences, subjective outcomes and selection of only event-free participants with complete data create substantial selection and confounding risks. This interim cohort may overlap later E-HD publications and is not counted as an independent participant cohort without confirmation. Nihon Trim and the Electrolyzed Water-Hemodialysis Study Group funded the work; two authors were Nihon Trim employees.
Maintenance-hemodialysis patients under this Japanese E-HD system; not evidence about drinking or inhaling H₂.
Not reported in this record.
Not reported in this record.
Not reported in this record.
No single-study GRADE certainty rating is assigned. Certainty is assessed by important outcome across a complete eligible evidence set, not by attaching a final grade to one source.
Sources and record status
PMID: 28902900 · DOI: 10.1371/journal.pone.0184535
Free full article on PLOS ONE and PubMed Central.
PLOS ONE and PMC full article, supporting protocol and PubMed metadata; full-text and article-status check completed 8 August 2026.
2026-08-10