Background: Intravenous iron therapy with ferric derisomaltose (FDI) has been shown to improve outcomes in patients with heart failure with reduced ejection fraction (HFrEF) and iron deficiency. However, its effects across different age groups remain unclear. This analysis of the Effectiveness of Intravenous Iron Treatment versus Standard Care in Patients with Heart Failure and Iron Deficiency (IRONMAN) trial explored the efficacy and safety of FDI across age groups. Methods: The IRONMAN trial was a prospective, open-label, blinded end point randomised controlled trial enrolling patients with HFrEF and iron deficiency. This prespecified analysis stratified the population into four quarters by age group: 79 years. The primary outcome was a composite of recurrent heart failure hospitalisations and cardiovascular death. Secondary outcomes included changes in haemoglobin and quality of life. Clinical outcomes comparing FDI versus usual care in each age subgroup were analysed by the method of Lin et al for recurrent events and Cox proportional hazards model for time to first event. Interactions between age and treatment effects were explored. Results: Among 1137 randomised patients (median age 73 years), the primary outcome rate ratio (FDI vs usual care) was 0.87 (95% CI 0.61 to 1.23) in patients 79 years (p-interaction=0.38). Improvements in haemoglobin and quality of life scores at 4 months did not differ statistically across age groups (p-interaction=0.92 and 0.64, respectively). Older patients were more symptomatic at baseline, with higher N-terminal-pro B-type natriuretic peptide levels and poorer renal function, but safety outcomes did not differ across age groups. Conclusions: We found no evidence that the effects of FDI on heart failure hospitalisations, cardiovascular death, haemoglobin and quality of life differed by age. These findings support its use in patients with HFrEF and iron deficiency, including older adults. Trial registration number: NCT02642562
