Phenotype-specific dynamics of serum albumin and their impact on sepsis mortality

To assess the prognostic value of serial serum albumin measurements in septic patients, with a focus on different clinical phenotypes.

We conducted a prospective observational study involving 254 patients with sepsis admitted to an Intermediate Care Unit in Italy (September 2022-June 2024). Patients were classified into four sepsis phenotypes (α, β, γ, δ), and serum albumin levels were measured daily over five days. The primary outcome was 30-day mortality. Logistic regression, Cox models, and AUROC analysis were used to evaluate associations between albumin dynamics, phenotypes, and outcomes.

The δ phenotype showed the lowest mean albumin levels (2.2 g/dL) and the highest mortality (45.4%), while phenotype α had the highest albumin and lowest mortality (3.6%). Each 1 g/dL increase in albumin was associated with a 63% mortality risk reduction (HR 0.37; 95% CI: 0.24-0.56). Albumin's predictive performance was strongest in the δ phenotype (AUROC up to 0.95).

Serial albumin monitoring may provide prognostic insights in sepsis, especially in phenotypes associated with endothelial dysfunction. These results are hypothesis-generating and may support more personalized treatment strategies.