Reviews/Heart Failure Management/Intravenous iron does not reduce all-cause mortality in heart failure
Iron · HFM-IRON-02 · v2
The one trial in this corpus that tested intravenous iron in exactly these patients, IRONMAN [12], found no difference in deaths between the iron group and usual care, and its main combined outcome of heart-failure hospitalisations plus cardiovascular death only trended toward benefit without reaching significance (RR 0.82, p=0.070). A follow-up look at the same trial [9] found what benefit there was clustered in more anaemic patients rather than showing a broad survival effect. No study here shows intravenous iron actually lowering overall deaths in heart failure. But the whole case rests on this single trial, the trial was built to answer a different question, and it never reports an exact number for the mortality effect. The panel therefore treated the direction as right but the foundation as thin.
The only usable primary trial in the exact population, IRONMAN [12], randomised 1137 patients with heart failure and iron deficiency and reported no between-group differences in deaths, with a primary composite of recurrent heart-failure hospitalisation and cardiovascular death that only trended (RR 0.82, 95% CI 0.66-1.02, p=0.070). Its secondary analysis [9] found the absence of anaemia or a TSAT of 20% or more was associated with little evidence of benefit, placing any signal in subgroups rather than in overall mortality. No primary-research paper in the corpus demonstrates intravenous iron reducing all-cause mortality in heart failure. Observational heart-failure data [8] likewise tie iron deficiency to hospitalisation outcomes but not to all-cause death, and other iron trials here sit in the wrong populations (pregnancy [3], ICU [7]). The contested point: The division is over what IRONMAN's null on deaths means: the trial was powered for a composite rather than all-cause mortality, and its composite CI (0.66-1.02) plus the prespecified COVID-sensitivity analysis (RR 0.76, p=0.047 in [12]) both lean toward benefit. So the evidence is consistent with no mortality reduction while not excluding one, and the abstract reports no mortality-specific effect estimate to settle it.
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IRONMAN was powered for a composite (recurrent HF hospitalisation and CV death), not all-cause mortality; the null death result is underpowered absence-of-evidence, not evidence of no effect, and the composite CI (0.66-1.02) and COVID-sensitivity RR 0.76 (p=0.047) both lean toward benefit.
The usable evidence is a single trial programme — [9] and [12] are both IRONMAN; the wider trial base (AFFIRM-AHF, HEART-FID, FAIR-HF) appears only in excluded editorials, so the claim's generality is not independently corroborated.
Where it remains uncertain. IRONMAN was powered for a composite, not all-cause mortality, and gives no mortality HR or CI [12], so the null is absence of evidence rather than evidence of no effect.
Aleatory
Deaths are a hard but infrequent endpoint, so chance variation in event counts limits what a single trial can resolve about a true mortality effect [12].
Epistemic
IRONMAN's abstract states no between-group differences in deaths but reports no all-cause mortality HR or CI, so magnitude and precision are unknown [12].
Inferential
IRONMAN was powered for recurrent HF hospitalisation and CV death, not all-cause mortality, so inferring a mortality conclusion from its design is indirect [12].
The load-bearing papers from a corpus of 12, each classified by what it does to the claim. Every DOI is taken from the corpus the claim was graded on.
Secondary IRONMAN analysis consistent with no broad mortality benefit; benefit, where seen, was event-driven and subgroup-limited.
“The absence of anaemia or a TSAT ≥ 20% was associated with lower event rates and little evidence of benefit from FDI.”
Panel auditInternal validity: low · scope of inference: Which iron/anaemia biomarker subgroups of HF patients may gain more from IV iron.Key limitations: post-hoc subgroup analysis · composite endpoint not all-cause mortality · not statistically significant
Directly supports the claim: the pivotal HF iron-deficiency RCT found no all-cause death difference between IV ferric derisomaltose and usual care.
“336 primary endpoints (22·4 per 100 patient-years) occurred in the ferric derisomaltose group and 411 (27·5 per 100 patient-years) occurred in the usual care group (rate ratio [RR] 0·82 [95% CI 0·66 to 1·02]; p=0·070)”
Panel auditInternal validity: medium · scope of inference: Longer-term cardiovascular effect of IV ferric derisomaltose in HF with EF ≤45% and iron deficiency.Key limitations: open-label · composite endpoint, all-cause mortality not isolated · primary endpoint borderline non-significant
2 of 12 papers shown. The full review lists all of them, with the panel’s arbitration →
Claims are graded at each quarterly release, and re-graded between releases only when a pivotal trial lands. Every change is a new version of the claim.
The direction is right and uncontradicted within the usable corpus, but the evidence is a single underpowered trial programme, warranting Likely rather than Established.
Release 2026-q4 re-graded every claim from its corpus under protocol v0.19. An earlier release's grade is shown for the record; it came from an earlier protocol and is not a movement.
Assumptions that carry weight but are not themselves established.
The panel records the gap that would most move the claim, and the study that would close it.
No mortality-powered trial or estimate. The claim is about all-cause mortality, yet the only direct trial was powered for a composite and reports no mortality HR or CI [12], so the effect's magnitude and precision are unquantified. The panel rates this the highest-importance open gap for the claim, and names the study design that would close it: An RCT or individual-patient meta-analysis powered for all-cause mortality in HF with iron deficiency, reporting a mortality HR with CI.
Open question: What is the all-cause mortality hazard ratio and confidence interval for IV iron in HF with iron deficiency? Why it is still open: IRONMAN's abstract reports only 'no between-group differences in deaths' with no HR or CI [12].
Priors is a sceptical first reader, not peer review, and not medical advice.
Release 2026-q4 · graded 21 Oct 2026 · protocol v0.19