Intravenous iron and SGLT2 inhibitors in iron-deficient patients with heart failure and reduced ejection fraction

To explore the potential interaction between use of SGLT2 inhibitors and the increase in haemoglobin in patients randomized to intravenous iron or the control group in the IRONMAN (Effectiveness of Intravenous Iron Treatment versus Standard Care in Patients with Heart Failure and Iron Deficiency) trial.

This was a post hoc exploratory analysis of the IRONMAN trial which randomized patients with heart failure, a left ventricular ejection fraction (LVEF) ≤ 45% and iron deficiency (transferrin saturation <20% or ferritin <100 μg/L) to open label intravenous ferric derisomaltose or usual care. Of the 1137 randomized patients, 29 (2.6%) were taking an SGLT2 inhibitor at baseline. The mean (SD) change in haemoglobin from baseline at 4 weeks in those taking an SGLT2 inhibitor at baseline was 1.3 (1.2) g/dL in patients randomized to ferric derisomaltose and 0.1 (0.7) g/dL in the usual care group; between-group difference = 1.0 g/dL (95% CI 0.1, 1.8). The equivalent numbers in the no SGLT2 inhibitor group were 0.6 (0.9) g/dL in those randomized to ferric derisomaltose and 0.1 (0.8) g/dL in the usual care group; between-group difference = 0.4 g/dL (95% CI 0.3, 1.6); interaction P value = 0.10. No patient receiving an SGLT2 inhibitor at baseline developed polycythaemia during follow-up (defined as haemoglobin >16.5 g/dL [men] or >16 g/dL [women]).

In the IRONMAN trial, there was a trend to a greater increase in haemoglobin with ferric derisomaltose in iron-deficient patients taking an SGLT2 inhibitor at baseline, as compared with those not taking one.