Association of admission vs. nadir serum albumin concentration with short-term treatment outcomes in patients with acute heart failure

OBJECTIVES: Hypoalbuminemia occurs in 25% to 76% of patients hospitalized for acute heart failure (HF) and is associated with increased mortality. Hypoalbuminemia may predispose patients to intravascular volume depletion, hypotension, and acute worsening of renal function; however, its association with treatment outcomes during hospitalization is unknown. METHODS: This retrospective cohort study involved 414 adult patients hospitalized for HF requiring intravenous diuretics. Temporal changes in serum albumin and the association of hypoalbuminemia with urine output, renal function changes, blood pressure, use of intravenous vasoactive drugs, and short-term outcomes were assessed. RESULTS: Serum albumin decreased in most patients (72%) during hospitalization. Hypoalbuminemia was present in 29% and 50% of patients based on the mean admission and nadir serum albumin level, respectively. Hypoalbuminemia as assessed by the nadir albumin level was associated with an increased risk of acute worsening of renal function. A nadir albumin level of <3.0 g/dL remained significantly associated in the multivariate analyses. CONCLUSIONS: Serum albumin commonly decreases during hospitalization for acute HF. Hypoalbuminemia assessed using the nadir level during hospitalization, not the admission level, was associated with an increased risk of acute worsening of renal function. The timing of serum albumin measurement may influence its utility as a biomarker.