Impact of hemoglobin increase in patients with acute kidney injury and severe anemia on major adverse kidney events.

Acute kidney injury (AKI) is frequently accompanied by severe anemia, raising concerns that impaired oxygen delivery may accelerate kidney dysfunction. However, the clinical benefit of early hemoglobin (Hb) correction remains uncertain. This study evaluated the association between early Hb correction and major adverse kidney events (MAKE). We conducted a single-center retrospective cohort including hospitalized adults with AKI and baseline severe anemia (Hb <8.0 g/dL). Patients were stratified according to whether they achieved Hb correction (>10 g/dL) within the first 10 days of hospitalization. The primary outcome was MAKE at 10 days (MAKE10), defined as death, initiation of kidney replacement therapy (KRT), or ≥25% decline in estimated glomerular filtration rate (eGFR). Secondary outcomes included individual MAKE components and MAKE at 90 days (MAKE90). Multivariable logistic regression models were adjusted for age, sex, and baseline eGFR. Among 232 patients, 47 (20.3%) achieved Hb correction. Baseline characteristics were comparable between groups. Although unadjusted analyses suggested a lower incidence of MAKE10 in the correction group, adjusted analyses showed no significant association (adjusted OR 1.04; 95% CI 0.41-2.62). Hb correction was nor associated with each individual components of MAKE or MAKE90. No differences were observed according to the correction strategy (transfusion alone vs transfusion plus erythropoiesis-stimulating agents). In this retrospective cohort of patients with AKI and severe anemia, early Hb correction to >10 g/dL was not associated with improved short- or medium-term outcomes. These findings support a conservative and individualized approach to anemia management during AKI, although residual confounding and selection bias cannot be excluded.