Background Red cell distribution width (RDW) is a surrogate of many aberrations (inflammation, malnutrition, iron deficiency (ID)) that may drive chronic heart failure (CHF) progression. While an elevated RDW and iron deficiency at baseline predict mortality in CHF, little is known about the prognostic implications of their temporal trends.
Methods We analysed the relation of red cell indices on first consultation and over time with mortality in 274 outpatients with CHF (mean (±SD) age 70±14 years, LVEF 28±8%, NYHA class 2±1, 54% ischaemic). The combination of a rising RDW and a falling mean cell volume (MCV) identified evolving ID.
Results On initial consultation, an RDW >15%, Hb<12.5 g/dl, and MCV <80 fl were evident in 41%, 46%, and 8% of patients. Over a median (±IQR) follow-up of 15±17 months, 60 (22%) patients died. On Cox proportional hazards analyses, a higher RDW independently predicted increased mortality (HR 1.21, p<0.0001). Over time, 51%, 58%, 40%, and 23% of patients had a rise in RDW, a fall in Hb, a fall in MCV, and evolving ID, respectively. A rising RDW predicted death (HR 1.18, p=0.002) independently of baseline RDWs and changes in Hb, with an absolute increase >1% conferring a twofold escalated risk of mortality (Abstract 107 figure 1A). Evolving ID was also associated with poorer survival (HR 2.89, p<0.0001, Abstract 107 figure 1B).
Conclusions An expanding RDW and evolving iron deficiency over time predict an amplified risk of death in CHF and could be utilised for risk stratification or therapeutically targeted to improve outcomes.
- Heart failure