Abstract
Background: Iron deficiency contributes to reduced exercise capacity in patients with heart failure. The repletion of iron improves cognitive, symptomatic, and exercise performance in these patients independent of hemoglobin. COPD shares many functional features of heart failure. Thus iron deficiency could be a potential therapeutic target in COPD.
Aims and objectives: The aim of this study was to determine the prevalence of iron deficiency in non-anemic patients with COPD.
Methods: Serum markers of iron status were measured in 53 stable non-anemic (hemoglobin>12 g/L) COPD patients (53% males; mean age 64±8 years, mean FEV1predicted 41±18%; GOLD stage II, III, and IV was 34%, 32%, and 34%, respectively). Iron deficiency was diagnosed when the serum ferritin level was either <100 μg/l or was between 100 and 299 μg/l with the transferrin saturation <20%.
Results: The serum ferritin level was <100 μg/l in 20 patients. The serum ferritin level was between 100 and 299 μg/l and transferrin saturation was <20% in 6 patients. Thus iron deficiency was present in 49% of the patients. The median soluble transferrin receptor to log_ferritin ratio was higher in patients with iron deficiency (1.7, 1.0 to 1.4) compared to patients without (1.7, 1.4 to 2.0), p<0.001.
Conclusions: Iron deficiency is present in half of the patients with stable COPD. A randomized, placebo-controlled trial should clarify whether repletion of iron stores improves functional performance in COPD patients with iron deficiency.
- © 2011 ERS