Non‐anaemic iron deficiency impairs response to pulmonary rehabilitation in COPD

Abstract

Background and objective: Non-anaemic iron deficiency (NAID) might alter the oxygen pathway in health and disease. The current study aims at assessing the impact of NAID on aerobic capacity in patients with chronic obstructive pulmonary disease (COPD). Methods: A prospective sample of 70 non-anaemic COPD patients candidate to participate in an 8-week pulmonary rehabilitation (PR) programme was studied. Incremental cycling exercise to peak oxygen uptake (V'O2peak) and constant work-rate exercise at 80% V'O2peak to exhaustion were assessed pre-and post-PR. Training-induced increase of endurance time (ET) ≥33%, which represented the minimal clinically important difference, classified patients as responders to exercise training. Results: The prevalence of NAID was 48% (n = 34) showing no relationship with the Global Initiative for Chronic Obstructive Lung Disease stages (P = 0.209). Patients with NAID showed lower pre-training ET (P = 0.033) and V'O2peak (P = 0.007) than normal iron status (NIS) patients after adjustment for potential covariates. Significant training-induced physiological changes were seen in the NIS group (ΔV'O2peak 68(132) mL/min; P = 0.009), but not in the NAID group (ΔV'O2peak 26 (126) mL/min; P = 0.269). The NAID group showed lower percentage of responders to training (56%) than the NIS group (78%) (P = 0.041). Conclusions: COPD patients with NAID showed lower pre-training aerobic capacity and reduced

The “Iron”-y of Iron Overload and Iron Deficiency in Chronic Obstructive Pulmonary Disease

“…Low Hb levels observed in anemic patients with COPD may result in lower exercise capacity and anaerobic threshold. In patients with NAID and COPD, exercise limitation might be a result of diminished oxygen use in the muscle cells caused by impaired function of iron-containing enzymes (96).…”

Clinical management of chronic obstructive pulmonary disease patients with muscle dysfunction

“…In fact, other beta-agonists such as clenbuterol or formoterol have demonstrated anabolic effects on muscle mass (253)(254)(255). It has very recently been shown that iron administration results in improvements in limb muscle function and exercise capacity, even in COPD patients without anemia (256). This would likely be the result of an improved transport and use of oxygen in the muscle by the action of proteins such as myoglobin and cytochrome C (mitochondrial respiratory chain), respectively (256,257).…”

Year in review 2015: Asthma and chronic obstructive pulmonary disease

“…110 However, there has been a gap in the literature about the effect of iron deficiency without acute anaemia despite the potential clinical implications associated with reductions in haemoglobin that may not achieve diagnostic criteria for anaemia but may impact pre-existing hypoxia. Barberan-Garcia et al 111 enrolled 34 COPD patients with non-anaemic iron deficiency (normal haemoglobin and low iron status) in a traditional pulmonary rehabilitation programme. Compared with COPD patients with normal haemoglobin and iron status, those with iron deficiency had initially lower exercise capacity and peak oxygen uptake.…”