Admission-measured C-reactive Protein-to-albumin Ratio as a Predictive Marker for Hospital-acquired Infections in Patients with Spontaneous Intracerebral Hemorrhage

Spontaneous Intracerebral Hemorrhage (ICH) is associated with a high risk of Hospital-Acquired Infections (HAIs), contributing to poor neurological outcomes and increased healthcare burden. Early identification of patients at elevated risk is critical, and the C-reactive protein-to-albumin ratio (CAR) has emerged as an integrative biomarker reflecting inflammatory and nutritional status.

A multicenter retrospective cohort study was conducted at three tertiary hospitals, including 2,355 adult patients with spontaneous ICH admitted within 72 hours of symptom onset. Admission CAR values were calculated from CRP and albumin measurements and analyzed for associations with subsequent HAIs using multivariable logistic regression, restricted cubic spline modeling, and weighted receiver operating characteristic curves.

Overall, 68.2% of patients developed HAIs, and higher admission CAR was independently associated with increased infection risk in a non-linear L-shaped pattern. CAR demonstrated moderate discrimination accuracy for overall HAIs (adjusted AUC 0.717) and was particularly effective for intracranial and bloodstream infections, with a threshold of 0.477 stratifying risk from 57.9% to 78.4% incidence.

The findings suggest that admission CAR is a practical biomarker for early HAI risk stratification in ICH patients, integrating inflammatory and nutritional parameters. The non-linear association and distinct contributions of CRP and albumin highlight the need for threshold-based risk categorization in clinical practice.

Admission CAR is a feasible and moderately accurate predictor of HAIs in spontaneous ICH. Its non-linear association, along with the distinct contributions of CRP and albumin, supports the use of threshold-based risk categorization to guide early surveillance and targeted preventive strategies.