Phenotyping heart failure patients for iron deficiency and use of intravenous iron therapy: data from the Swedish Heart Failure Registry

Aims: Iron deficiency (ID) is associated with poor prognosis regardless of anaemia. Intravenous iron improves quality of life and outcomes in patients with ID and heart failure (HF) with reduced ejection fraction (HFrEF). In the Swedish HF registry, we assessed (i) frequency and predictors of ID testing; (ii) prevalence and outcomes of ID with/without anaemia; (iii) use of ferric carboxymaltose (FCM) and its predictors in patients with ID.

Methods and results: We used multivariable logistic regressions to assess patient characteristics independently associated with ID testing/FCM use, and Cox regressions to assess risk of outcomes associated with ID. Of 21 496 patients with HF and any ejection fraction enrolled in 2017-2018, ID testing was performed in 27%. Of these, 49% had ID and more specifically 36% had ID-/anaemia-, 15% ID-/anaemia+, 29% ID+/anaemia-, and 20% ID+/anaemia+ (48%, 39%, 13%, 30% and 18% in HFrEF, respectively). Risk of recurrent all-cause hospitalizations was higher in patients with ID regardless of anaemia. Of 1959 patients with ID, 19% received FCM (24% in HFrEF). Important independent predictors of ID testing and FCM use were anaemia, higher New York Heart Association class, having HFrEF, and referral to HF specialty care.

Conclusion: In this nationwide HF registry, ID testing occurred in only about a quarter of the patients. Among tested patients, ID was present in one half, but only one in five patients received FCM indicating low adherence to current guidelines on screening and treatment.