Early hemoglobin levels after kidney transplantation predict clinical outcomes

The impact of early hemoglobin levels following kidney transplantation (KT) on long-term outcomes remains unclear. This study evaluates the association between early posttransplant hemoglobin levels and clinical outcomes.

A total of 7,501 kidney transplant recipients (KTRs) from a nationwide cohort were included. Hemoglobin levels at 6 months post-KT were analyzed. KTRs were categorized into five hemoglobin groups: <10, 10 to <11, 11 to <12, 12 to <13 (reference group), and ≥13 g/dL. The primary outcome was a composite of cardiovascular events, graft loss, and all-cause mortality. Multivariable Cox regression was employed to assess the relationship between hemoglobin levels and the composite outcome.

The cohort had a mean age of 49.6 ± 11.6 years, and 60.4% were male. The incidence of the composite outcome and its individual components was highest among KTRs with hemoglobin levels <10 g/dL. Hemoglobin levels <10 g/dL were associated with a significantly increased risk of the composite outcome (hazard ratio [HR], 3.16; 95% confidence interval [CI], 2.05-4.87; p < 0.001) and were identified as an independent risk factor for each component. Conversely, hemoglobin levels ≥13 g/dL were associated with improved survival (HR, 0.44; 95% CI, 0.22-0.90; p = 0.02). Subgroup analyses confirmed that hemoglobin levels <10 g/ dL consistently increased the risk of the composite outcome.

Posttransplant anemia with hemoglobin levels <10 g/dL showed a significant association with an increased risk of the composite outcome. Conversely, hemoglobin levels ≥13 g/dL were linked to better patient survival.