# Baseline Serum Albumin for Long-Term Risk Stratification in Maintenance Hemodialysis Patients: A Retrospective Cohort Study

## TL;DR

Low baseline serum albumin levels predict higher long-term mortality in hemodialysis patients, suggesting it could help identify those at greater risk.

## Contribution

This study establishes serum albumin as an independent predictor of long-term mortality in hemodialysis patients over up to 10 years.

## Key findings

- Lower baseline serum albumin (<3.5 g/dL) was associated with significantly higher mortality (76.2% vs. 43.4%).
- Albumin <3.5 g/dL remained an independent predictor of mortality (hazard ratio 1.84) in multivariate analysis.
- A cutoff of 3.4 g/dL was identified as optimal for predicting mortality (area under the curve 0.72).

## Abstract

Background/Objectives: Mortality among patients receiving maintenance hemodialysis remains high, and biomarkers that allow early risk stratification are needed. Serum albumin reflects nutritional status and systemic inflammation and has been associated with adverse outcomes; however, its long-term prognostic significance remains incompletely defined. This study examined the association between baseline serum albumin and long-term (up to 10-year) all-cause mortality in a large hemodialysis cohort. Methods: This retrospective cohort study included adult patients undergoing maintenance hemodialysis between 2015 and 2025 at a tertiary nephrology center. Individuals with at least three months of stable dialysis and available baseline serum albumin measurements were included. Patients were categorized into two groups according to baseline serum albumin levels (<3.5 g/dL and ≥3.5 g/dL). The primary outcome was long-term (up to 10-year) all-cause mortality, while secondary outcomes included emergency department visits, hospital admissions, cardiovascular events, and infection-related hospitalizations. Survival was assessed using Kaplan–Meier analysis, and predictors of mortality were evaluated using Cox proportional hazards regression. The median follow-up duration was 54 months (interquartile range: 28–92), with a maximum follow-up of 10 years. Results: A total of 412 patients were analyzed, of whom 40.8% had serum albumin levels < 3.5 g/dL. During follow-up, 233 deaths occurred. Lower albumin levels were associated with significantly higher mortality (76.2% vs. 43.4%, p < 0.001), increased healthcare utilization, and a greater incidence of cardiovascular and infectious complications. In multivariate analysis, albumin < 3.5 g/dL remained an independent predictor of mortality (hazard ratio 1.84, 95% confidence interval 1.42–2.38; p < 0.001). Receiver operating characteristic analysis identified 3.4 g/dL as the optimal cutoff for mortality prediction (area under the curve 0.72). Conclusions: Baseline serum albumin is an independent predictor of long-term (up to 10-year) mortality and adverse clinical outcomes in patients receiving maintenance hemodialysis. Although albumin is not a causal determinant, its association with survival likely reflects underlying nutritional and inflammatory burden. Prospective multicenter studies are warranted to validate albumin-based risk stratification and to evaluate the prognostic value of longitudinal changes in serum albumin over time.