Life after kidney transplantation is becoming increasingly important due to the growing number of patients receiving kidney grafts. Therefore, there is a pressing need for interventions to improve patient-reported outcomes following kidney transplantation.
A recent study from PhD students and Transplantlines researchers Daan Kremer and Tim Knobbe and research leader Michele Eisenga, nephrologist in training, shows that in kidney transplant recipients (KTRs), iron deficiency, independent of anaemia, is associated with worse patient-reported outcomes (PROs), including more fatigue, worse concentration, more anxiety, more depressive symptoms, and lower overall health-related quality of life (HRQoL). The results have been published in the top journal of the field: the American Journal of Transplantation.
Traditionally, iron status has been primarily assessed in relation to anaemia. However, iron serves numerous functions beyond simply supporting red blood cell production. For instance, it plays vital roles in muscle function, brain health, and cardiovascular function. The study highlights the broader impact of iron deficiency beyond its association with anaemia.
The study used data from 814 kidney transplant recipients visiting outpatient clinics (62% men, average age 56 years) who took part in TransplantLines: a large prospective cohort study and biobank to provide a better understanding of disease-related and ageing-related outcomes and health problems, both physical and psychological, in solid organ transplant recipients and living organ donors.
The study shows that 28% of the kidney transplant recipients had iron deficiency and 29% had anaemia, according to World Health Organization criteria. Analyses showed that iron deficiency, but not anaemia, was linked to feeling more tired, having poorer concentration, lower wellbeing, more anxiety, more depressive symptoms, and worse overall quality of life. These associations held up even after considering factors like age, sex, kidney function, and anaemia.
In fact, in fully adjusted models, iron deficiency was associated with a 53% higher risk of severe fatigue, twice the risk of major depressive symptoms, and a 51% higher chance of facing sick leave or work disability.
The study sheds light on whether we should contemplate iron correction for transplant patients solely on the basis of iron deficiency without anaemia. Currently, a trial is underway examining various outcomes regarding the impact of iron infusion in KTRs, which could provide further guidance in answering this question.
Link to publication: https://www.amjtransplant.org/article/S1600-6135(24)00213-2/fulltext
