The Iron and Muscle Study

This is a multi-center randomized controlled trial that will examine the efficacy of IV iron supplementation when compared to placebo, with and without exercise training, on changes in patient exercise capacity. The study aims to provide sufficient data to inform a power calculation for the definitive study to examine whether IV iron therapy in patients with CKD stages 3-4 (non-dialysis) can improve exercise capacity, muscle metabolism and physical function. Specifically, we propose to examine whether a strategy of IV iron therapy in patients with stages 3-4 CKD who are iron-deficient but NOT anaemic leads to improvements in exercise capacity. Very little is currently known about the effects of iron deficiency on cardiac or skeletal muscle metabolism in patients suffering from CKD. Nevertheless, it seems likely that iron deficiency will contribute to mitochondrial dysfunction and reduced energy production in cardiac or skeletal muscle of CKD patients, and importantly may contribute to the reduced exercise capacity, physical function and overwhelming fatigue commonly reported in this population. The results of this trial will provide data to ascertain whether intravenous iron therapy might be beneficial to exercise capacity, muscle metabolism, physical function, and fatigue and whether iron repletion enhances the effect of an exercise intervention.