Association of serum albumin levels with multidomain functional impairment (motor, balance, ADL, and cognitive impairment) in Chinese post-stroke patients: a multicenter cross-sectional study.

BACKGROUND

Malnutrition, frequently indicated by hypoalbuminemia, is prevalent post-stroke and associated with adverse functional outcomes. However, the independent role of serum albumin (ALB) in multidomain functional recovery-encompassing motor, balance, cognitive, and daily living domains-remains underexplored in Chinese populations. This multicenter study aimed to quantify the independent association between serum ALB levels and functional impairment in Chinese post-stroke patients.

METHODS

In this cross-sectional study, 1,741 patients from rehabilitation centers across China were enrolled. ALB levels were categorized into quartiles (Q1: <37.7 g/L; Q2: 37.7-40.0 g/L; Q3: 40.0-42.8 g/L; Q4: ≥42.8 g/L). Outcomes included motor function (Fugl-Meyer Assessment), activities of daily living (Modified Barthel Index), balance (Berg Balance Scale), and cognition (Montreal Cognitive Assessment). Multivariable linear regression models adjusted for demographics, comorbidities, lesion characteristics, and illness duration. Subgroup analyses tested interactions by age, sex, BMI, and lesion topography.

RESULTS

Each 1-g/L ALB increase independently predicted functional gains: FMA (β = 1.35, 95% CI: 0.99-1.72), ADL (β = 1.77, 1.44-2.10), BBS (β = 1.02, 0.78-1.26), MoCA (β = 0.30, 0.21-0.40) (all p < 0.001). Dose-dependent improvements were observed across quartiles (Q4 vs. Q1: FMA Δβ = 15.11 [11.09-19.12]; ADL Δβ = 19.35[15.76-22.93]; P trend < 0.001). Sex significantly modified ALB-FMA associations (P interaction = 0.017), with females showing stronger effects (β = 1.81 [1.12-2.51]) than males (β = 1.15 [0.72-1.58]). Cerebellar lesions demonstrated non-significant trend toward amplified associations (FMA: β = 2.16 [0.72-3.59]).

CONCLUSION

ALB levels are independently and dose-dependently associated with motor, ADL, balance, and cognitive function in post-stroke patients. Compared to lower quartiles, patients with ALB ≥42.8 g/L (highest quartile) exhibit superior functional outcomes. A sex-specific pattern is observed solely in motor function, where the correlation is more pronounced in females. ALB may serve as a biological indicator for risk stratification during stroke rehabilitation.