Expert Perspectives on Managing Iron Deficiency in People with CKD and/or HF

<b>Background:</b> Iron deficiency (ID) is common among people with chronic kidney disease (CKD) and/or heart failure (HF). Despite the additional burden ID causes among people with CKD and HF, there is considerable uncertainty surrounding the best way to diagnose it and, subsequently, identify who is most likely to benefit from receiving iron therapy. <b>Methods:</b> This manuscript reports the markers and thresholds used in ID diagnosis, treatment, and management in the UK by nephrologists and cardiologists who manage people with chronic kidney disease or heart failure, as well as investigating future challenges and questions that remain unanswered. The research involved three stages: an online questionnaire, individual interviews, and a panel meeting, which discussed the findings from the first two stages. <b>Results:</b> The panel concluded that there is no robust definition of iron deficiency that can be applied to chronic kidney disease and heart failure. Existing methods of diagnosing iron deficiency come with various problems; a transferrin saturation of <20% is the most popular, but it is not regarded as a perfect solution. Transferrin saturation is also the most popular way of assessing the success of iron deficiency treatment. Clinicians generally do not vary treatment regimens based on severity or subgroups. There are large variations in monitoring and the ability to administer iron therapy in secondary care. <b>Conclusions:</b> There is a clear need to consolidate current approaches to diagnosing and treating iron deficiency in people with chronic kidney disease and/or heart failure. Simple markers and thresholds, and simple strategies to implement them are required.