Anemia after kidney transplantation; its prevalence, risk factors, and independent association with graft and patient survival: a time-varying analysis.

Introduction Posttransplant anemia and its association with transplant outcomes have not been properly studied. Methods We examined 530 renal allograft recipients transplanted at our center and followed up for 31.0±14.1 months. Hemoglobin (Hb), serum bicarbonate, and creatinine; use of erythropoiesis-stimulating agent (ESA) and iron; and immunosuppressive regimen data were obtained at multiple time points during 24-month posttransplant. Results The overall prevalence of anemia was 89.4% at the time of transplant, dropping to 49.2% at 1 year and 44.3% at 2 years. ESA use decreased from 25.6% at 1 month to 8.23% at 24 months, only in 30.9% to 51.2% with severe anemia; 21.0% to 29.2% received iron supplements. Factors independently predictive of Hb included male gender (β=0.64, P 10 mg/day vs. none). Using a competing-risk regression model, Hb less than 9 in men and less than 8 in women, was associated with 5.25-fold higher risk of death-censored graft loss compared with no anemia (adjusted, P=0.005, CI: 1.7–16.7). Degree of anemia also remained significantly associated with risk of death (hazard ratio [HR]: 2.2, P Conclusion We showed that posttransplant anemia is common, and ESA/iron use remains suboptimal, and Hb is independently associated with graft failure and mortality.