Prevalence and factors influencing anemia recovery after intensive care

Background: Anemia is associated with adverse outcomes and prolonged hospitalizations in critically ill patients. Regarding the recent adoption of restrictive transfusion protocols in intensive care unit (ICU) management, anemia remains highly prevalent even after ICU discharge. This study aimed to investigate the prevalence of anemia following ICU discharge and factors affecting recovery from anemia. Methods: In this retrospective cohort study involving 3969 adult ICU survivors, we assessed anemia severity using the National Cancer Institute criteria at six time points: ICU admission, ICU discharge, hospital discharge, and at 3-, 6-, and 12-month post-hospital discharge. In addition, baseline characteristics, including age, sex, comorbidities, and recent iron supplementation or erythropoietin administration, were evaluated. Results: Our findings revealed an in-hospital mortality rate of 28.6%. The median hospital and ICU stays were 20 and 5 days, respectively, with common comorbidities including hypertension, and diabetes mellitus (DM). Among the patients, the hemoglobin levels of 3967 patients were confirmed at the time of discharge from the ICU, representing 99.95% of the total. The prevalence of anemia persisted post- ICU discharge; less than 30% of patients recovered, whereas 13.6% of them experienced worsening of anemia post-ICU discharge. Factors contributing to anemia severity were female sex, DM, chronic renal failure, malignant solid tumors, and administration of iron supplements. Conclusions: This study highlighted the need for targeted interventions to manage anemia post-ICU discharge and suggested potential factors that influence recovery from anemia.