A systematic review and meta-analysis of factors contributing to post-kidney transplant anemia and the effect of erythropoietin-stimulating agents
Kittiphan Chienwichai, Supitchaya Phirom, Thunyatorn Wuttiputhanun, Asada Leelahavanichkul, Natavudh Townamchai, Yingyos Avihingsanon, Suwasin Udomkarnjananun
Abstract
The effects of various risk and associated factors on post-kidney transplant anemia (PTA) have not been fully compared and estimated. This meta-analysis aims to elucidate factors contributing to PTA and determine the influence of erythropoietin-stimulating agents (ESAs) on renal outcomes, thus offering potential pathways for enhanced management strategies post-transplant. A systematic review was conducted in electronical database. Studies reporting on risk factors (with cause-effect relationships) and associated factors (without definite cause-effect relationships) of PTA, and the effects of ESAs on post-kidney transplant outcomes, were included. Pooled odds ratios (ORs) and weighted mean differences (WMDs) were analyzed using random-effects models. This systematic review encompassed 38,233 patients from 85 studies. Factors increased PTA risk included African American, older donor age, human antigen leukocyte mismatches, and low pre-transplant hemoglobin levels. Poor allograft function, high interleukine-6, Cytomegalovirus, delayed graft function, allograft rejections, immunosuppressive medications, and renin-angiotensin system blockades were associated with PTA. Native autosomal dominant polycystic kidney disease was a protective factor against PTA. Administration of ESAs with the aim of normalizing hemoglobin levels in patients with chronic allograft dysfunction slowed the decline in eGFR and reduce the risk of death, with a pooled OR of 0.36 (95% CI: 0.14 to 0.89; p = 0.040). The risks and associated factors for PTA have been elucidated, underscoring the need for individualized treatment approaches. Late ESA therapy, aimed at hemoglobin normalization, suggests a renal-protective effect and reduced mortality, which should be considered in the management of PTA. PROSPERO CRD42024545330. What was known • Post-kidney transplant anemia (PTA) leads to poor transplant outcomes, including graft loss and death, though the precise impact of each contributing factor remains unclear. This study adds • This meta-analysis identified several risk and associated pre- and posttransplant factors, such as donor age, cause of kidney disease, immunosuppressive medications, human leukocyte antigen mismatch, and allograft function, which contribute to PTA. • The use of erythropoietin-stimulating agents (ESA) in recipients with chronic allograft dysfunction improved allograft function and reduced mortality. Potential impact • Factors contributing to PTA were identified and should be used to identify patients at risk. • ESA therapy in patients with chronic allograft dysfunction is beneficial and should therefore be integrated in the recommendations for late posttransplantation care.