Intravenous iron therapy for patients with heart failure: a meta-analysis stratified by chronic kidney disease status.

Iron deficiency is highly prevalent in patients with heart failure (HF) complicated by chronic kidney disease (CKD), yet the efficacy of intravenous (IV) iron therapy remains unclear. We performed a meta-analysis of randomized controlled trials (RCTs) retrieved from Embase, PubMed, and the Cochrane Library from inception to January 1, 2026. A total of 8 RCTs involving 7009 participants were included. Clinical outcomes were assessed by generating forest plots using the random-effects model and pooling relative risks (RRs) or mean differences (MDs). IV iron therapy showed a significantly reduced incidence of first heart failure hospitalization or cardiovascular death (RR = 0.79, 95% CI: 0.72–0.86, P < 0.001), heart failure hospitalization or cardiovascular death (RR = 0.85, 95% CI: 0.75–0.98, P = 0.02) in HF-CKD patients as compared with the control group, with significant improvements in relevant biomarkers. Subgroup analyses revealed no effect modification by CKD status. Anemia status modified the treatment effect on all-cause mortality (P = 0.04). Anemic patients exhibited a trend toward clinical benefit (RR = 0.84, 95% CI: 0.70–1.01, P = 0.06), while no such trend was observed in non-anemic patients (RR = 1.28, 95% CI: 0.90–1.81, P = 0.16). Further large-sample, long-term trials are needed to identify the optimal patient population and clarify the long-term safety of this therapy.