115 Prognostic significance of iron deficiency status in chronic inflammatory cardiomyopathy

Abstract

Abstract Aims Iron deficiency (ID) and associated anaemia (IDA) represent major comorbidities in chronic diseases. However, their prevalence and prognostic significance have never been investigated in chronic inflammatory cardiomyopathy (CIC). Methods and results This is a single-centre, prospective study, on consecutive adult patients with CIC (symptom onset > 3 months, endomyocardial biopsy-proven chronic myocarditis) undergoing iron status assessment (enrollment: January 2014–January 2019). ID was defined as either serum ferritin < 100 µg/l or transferrin saturation < 20%. IDA was defined as haemoglobin < 12 g/dl in women, < 13 g/dl in men. The primary endpoint was the occurrence of heart failure events (HFE) and/or arrhythmic events (AE). The study cohort is composed by 219 CIC patients (mean age 46 ± 15 y, 71% males, mean LVEF 50 ± 14%). Diagnosis was furtherly supported by cardiac magnetic resonance in 194 cases (89%). Baseline characteristics of patients with IDA (n = 48), ID (n = 70), and non-ID controls (n = 101) were largely comparable. We found that median in-hospital stay length was 13 days (IQR: 6–20) in IDA patients vs. 8 (IQR: 5–11) in the remaining groups (P = 0.002), and was inversely correlated with haemoglobin values on admission. By 3.9 ± 1.8 year prospective follow-up, events occurred in 86 patients (39%). For the composite endpoint, the only factors associated with events were ID status (HR: 6.3, 95% CI: 2.1–19.5, P = 0.001) and male gender (HR: 5.4, 95% CI: 1.2–24.9, P = 0.030). In detail, HFE occurred in 48 patients (40/118 IDA or ID vs. 8/101 controls, P < 0.001), and AE in 51 (34/118 IDA or ID vs. 17/101 controls, P = 0.039). All cardiac deaths (n = 7) occurred in ID or IDA patients (P = 0.016; n = 1 and 6, respectively). Conclusions ID and IDA are common among CIC patients, and may bare a negative prognostic value. Our findings suggest a careful evaluation of haemoglobin levels and iron status, and call for further investigation on both pathophysiological and prognostic implications of ID and IDA among CIC patients.