Background and Aims: The topic of management of chronic kidney disease (CKD) anemia has constantly been improving. This study aimed to assess the prevalence and current trends in anemia treatment in real-world kidney transplant recipients (KTR).

Methods: This cross-section study included 509 KTR patients, mean age – of 53 years, 51.5% male, with functioning grafts in the late post-transplant period in the last quarter of 2021, in an average of 9,4 years post-transplantation. Data were analyzed using SPSS Statistics 27.0. Student's t-test, Chi-squared test, Pearson correlation tests were used. According to the Kidney Disease: Improving Global Outcomes (KDIGO) definition, anemia was determined as a hemoglobin (Hb) level of <120 g/L for women and <130 g/L for men. CKD stage was determined by the estimated glomerular filtration rate (eGFR) calculated using creatinine in the CKD-EPI equation.

Results: The prevalence of anemia in the KTR population was 35% (n=178), increasing from 13% to 96% by progressing CKD from stage 1 to 5 in a transplant (Table 1: The prevalence of anemia depends on the stage of CKD in a transplant.)  A moderately strong Pearson correlation was recognized between the stage of CKD and anemia (r=0.441; p<0.001). A statistically significant association (p<0.001) was detected between anemia and the female gender (n=107; 60% of all anemic patients). We found no significant association between anemia and the use of mycophenolate or calcineurin inhibitors. Still, there was a statistically significant association between steroid use and anemia (p=0.041), with a 31% (Odds Ratio = 0.69) less chance of anemia in a group that received steroid therapy. 90% of anemic patients had normochromic, normocytic anemia, 7,8% hypochromic, microcytic, and 2,2% hyperchromic, macrocytic anemia. The treatment involved iron replacement in 29% (n=51) of patients, of whom 92.2% had oral medication and 7.8% intravenous. 54% (n=96) of anemic KTR received treatment with erythropoiesis-stimulating agents (ESAs): 27,1% with darbepoetin alfa and 72,9% with methoxy polyethylene glycol-epoetin beta. Anemia was corrected up to Hb level >110 g/L in 69.7% (n=67) of ESAs receiving KTR. A statistically significant correlation was not detected between the ESAs dosage (µg/kg) and the correction of the anemia (p=0.217).

Conclusion: Like in the general CKD population, the prevalence of anemia in KTR increases as CKD progress in a transplant. The extent of anemia correction seems insufficient, although it includes both major components: iron replacement and ESAs. We found anemia more prevalent in female patients and those not receiving steroids in the immunosuppressive regimen. This last unexpected finding needs further exploration.