C‑Reactive Protein to Albumin Ratio Predicts Early Mortality in Hospitalized Older Patients, Independent of the Admission Diagnosis

Background: Malnutrition and systemic inflammation are prevalent among older hospitalized patients and are associated with increased morbidity and mortality. The C-reactive protein to albumin (CRP/Alb) ratio reflects both inflammatory and nutritional status and may serve as a useful prognostic biomarker. Objective: To evaluate the prognostic value of the CRP/Alb ratio in predicting early in-hospital mortality in a large cohort of elderly patients, independent of the admission diagnosis. Methods: This retrospective observational study analyzed data from 2780 patients aged ≥ 65 years admitted to the Internal Medicine and Aging Department of the “Policlinico Riuniti” University Hospital in Foggia, Italy, between 2019 and 2024. Serum CRP and albumin values were recorded at admission. ROC curve analysis, Cox regression, and Kaplan–Meier survival analyses were conducted to assess the predictive power of the CRP/Alb ratio for in-hospital mortality at 7 and 30 days. Results: In-hospital mortality occurred in 444 patients (16%). Deceased patients had significantly higher CRP/Alb ratios compared to survivors (p < 0.001). The CRP/Alb ratio showed a strong association with early mortality, particularly within the first 7 days (AUC = 0.888). A CRP/Alb ratio >8 was an independent predictor of 30-day mortality (HR = 3.82, 95% CI: 2.91–5.01) and 7-day mortality (HR = 10.17, 95% CI: 6.05–17.08). Similar results were observed among re-hospitalized patients. Conclusion: The CRP/Alb ratio is a significant and independent predictor of early in-hospital mortality in elderly patients, regardless of admission diagnosis. A threshold value > 8 identifies individuals at high risk, particularly within the first week of hospitalization. This simple, cost-effective biomarker may support early risk stratification and guide targeted interventions in geriatric care.