Impact of albumin infusion on prognosis of intensive care unit patients with congestive heart failure-hypoalbuminemia overlap: a retrospective cohort study

Background: Hypoalbuminemia is common in congestive heart failure (CHF) patients. Serum albumin is associated with the prognosis of CHF patients. Impact of albumin infusion on prognosis of patients with CHF-hypoalbuminemia overlap remains unclear. We retrospectively investigated the impact of albumin infusion on prognosis of intensive care unit (ICU) patients with CHF-hypoalbuminemia overlap. Methods: We enrolled all patients whose diagnosis included CHF [ICD-9 (international classification of diseases 9) code =428.0] at first ICU admission from the MIMIC III (Medical Information Mart for Intensive Care III) database, and excluded those with missing serum albumin values, with serum albumin 3.4 g/dL or <18 years old. According to the exposure of albumin infusion during hospitalization, patients were stratified into non-albumin and albumin groups. Propensity-score matching (PSM) was performed (1:1 ratio) to control for baseline confounding. Outcome measures were in-hospital mortality as well as length of stay in the ICU (ICU LOS) and the hospital (hospital LOS). Results: There were 3,190 eligible patients in the initial search. Patients with albumin infusion had markedly higher in-hospital mortality (36.42% vs. 21.81%, P<0.001), longer ICU LOS [median 6.93 (3.39??? 14.82) days vs. 3.84 (1.96???8.00) days, P<0.001], and longer hospital LOS [median 17.46 (11.45???28.33) days vs. 10.92 (6.81???18.00) days, P<0.001] than those without albumin infusion. The multivariate logistic regression analysis revealed that albumin infusion [OR (odds ratio), 1.509; 95% CI (confidence interval), 1.164???1.957; P=0.002] was significantly associated with increased risk of in-hospital mortality. After PSM, a cohort of 429 pairs of patients was included in the final analysis. Patients with albumin infusion had markedly higher in-hospital mortality (34.97% vs. 27.27%, P=0.015), longer ICU LOS [median 8.43 (4.33???16.28) days vs. 6.43 (3.07???13.66) days, P<0.001], and longer hospital LOS [median 16.92 (11.27???28.06) days vs. 13.33 (8.00???21.10) days, P<0.001] than those without albumin infusion. The multivariate logistic regression analysis revealed that albumin infusion (OR, 1.594; 95% CI, 1.143???2.223; P=0.006) was significantly associated with increased risk of in-hospital mortality. Conclusions: Albumin infusion increased in-hospital mortality, ICU LOS, and hospital LOS in ICU patients with CHF-hypoalbuminemia overlap.