Impact of Iron Deficiency on Short-Term Clinical Outcomes in Patients Admitted With Acute Heart Failure at Benjamin Mkapa Hospital: A Prospective Cohort Study

Abstract Introduction: Iron deficiency is a common but under-recognized comorbidity in acute heart failure (AHF) and is associated with poor outcomes. However, data on its impact on short-term outcomes among AHF patients in Tanzania remain limited. This study assessed the association between absolute iron deficiency (AID) and short-term outcomes among patients admitted with AHF at Benjamin Mkapa Hospital (BMH). Methods A prospective cohort study was conducted among adults admitted with AHF at BMH between January 2025 and June 2026. AID was defined as serum ferritin < 100 ng/mL. Participants were followed for 90 days. The primary outcome was a composite of all-cause mortality or hospital readmission. Secondary outcomes included quality of life (KCCQ-12 score), NYHA functional status, and length of hospital stay. Kaplan-Meier and Cox regression assessed the primary outcome; secondary outcomes were compared using parametric or non-parametric tests as appropriate. Results A total of 339 participants were enrolled, of whom 330 (97.3%) completed follow-up. The mean age was 61.5 ± 15.5 years, 176 (53.0%) were female and 175 (53.0%) participants had AID. During follow-up, 63 (19.0%) experienced the composite endpoint. Participants with AID had lower event-free survival than those without (72.5% vs. 90.3%, log-rank p < 0.001). After adjustment, AID was independently associated with the composite endpoint (AHR 2.25, 95% CI 1.21–4.17; p = 0.010). At 90 days, AID participants had poorer NYHA functional status, with more remaining in class IV (20.0% vs. 11.6%) and fewer reaching class II (28.0% vs. 37.4%; χ²=21.20, p < 0.001). Participants with AID had a smaller improvement in KCCQ-12 scores (4.1 ± 9.8 vs. 9.2 ± 8.8 points; p < 0.001), and hospital stay was longer (7.9 ± 2.5 vs. 6.8 ± 2.2 days; p < 0.001). Conclusion AID is common among patients admitted with AHF and is independently associated with poorer short-term clinical outcomes. Larger multicentre studies with longer follow-up are needed to confirm these findings.