TR
EN
C-reactive protein to albumin ratio as a prognostic marker in community-acquired pneumonia mortality
Abstract
Aim: This study aimed to evaluate the prognostic value of the C-reactive protein-to-albumin ratio (CAR) in predicting 30-day mortality among patients diagnosed with community-acquired pneumonia (CAP) presenting to the emergency department (ED).
Material and Methods: A retrospective study was conducted on 312 patients diagnosed with CAP who presented to the ED of a tertiary care hospital between January 1, 2022, and January 1, 2024. Demographic, clinical, and laboratory data were collected, including C-reactive protein (CRP) and albumin levels. CAR was calculated by dividing CRP levels (mg/dL) by albumin levels (g/L). The primary outcome was 30-day mortality. The prognostic performance of CAR was evaluated using receiver operating characteristic (ROC) curve analysis.
Results: Of the 312 patients included, 87 (27.9%) died within 30 days. The deceased group had significantly higher CAR values compared to survivors (1.18 ± 0.62 vs. 0.52 ± 0.25, p < 0.001). CAR demonstrated excellent discriminatory power for predicting 30-day mortality, with an area under the curve (AUC) of 0.837 (95% CI: 0.791–0.876, p < 0.001). At a cut-off value of >0.77, CAR achieved a sensitivity of 75.9% and a specificity of 86.7%. Deceased patients also exhibited significantly lower systolic and diastolic blood pressures, oxygen saturation, and albumin levels, along with higher CRP levels and respiratory rates. Comorbidities such as stroke and congestive heart failure were more prevalent in the deceased group compared to survivors.
Conclusion: The C-reactive protein-to-albumin ratio is a reliable prognostic marker for predicting 30-day mortality in CAP patients presenting to the ED. Its ease of calculation and strong discriminatory power make CAR a valuable tool for risk stratification and clinical decision-making. Prospective studies are warranted to confirm these findings in diverse populations.
Keywords
References
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Details
Primary Language
English
Subjects
Emergency Medicine
Journal Section
Research Article
Publication Date
March 25, 2025
Submission Date
February 15, 2025
Acceptance Date
March 20, 2025
Published in Issue
Year 2025 Volume: 16 Number: 1
APA
Ustaalioğlu, İ., & Kibici, Ö. (2025). C-reactive protein to albumin ratio as a prognostic marker in community-acquired pneumonia mortality. Turkish Journal of Clinics and Laboratory, 16(1), 180-185. https://doi.org/10.18663/tjcl.1640626
AMA
1.Ustaalioğlu İ, Kibici Ö. C-reactive protein to albumin ratio as a prognostic marker in community-acquired pneumonia mortality. TJCL. 2025;16(1):180-185. doi:10.18663/tjcl.1640626
Chicago
Ustaalioğlu, İzzet, and Özge Kibici. 2025. “C-Reactive Protein to Albumin Ratio As a Prognostic Marker in Community-Acquired Pneumonia Mortality”. Turkish Journal of Clinics and Laboratory 16 (1): 180-85. https://doi.org/10.18663/tjcl.1640626.
EndNote
Ustaalioğlu İ, Kibici Ö (March 1, 2025) C-reactive protein to albumin ratio as a prognostic marker in community-acquired pneumonia mortality. Turkish Journal of Clinics and Laboratory 16 1 180–185.
IEEE
[1]İ. Ustaalioğlu and Ö. Kibici, “C-reactive protein to albumin ratio as a prognostic marker in community-acquired pneumonia mortality”, TJCL, vol. 16, no. 1, pp. 180–185, Mar. 2025, doi: 10.18663/tjcl.1640626.
ISNAD
Ustaalioğlu, İzzet - Kibici, Özge. “C-Reactive Protein to Albumin Ratio As a Prognostic Marker in Community-Acquired Pneumonia Mortality”. Turkish Journal of Clinics and Laboratory 16/1 (March 1, 2025): 180-185. https://doi.org/10.18663/tjcl.1640626.
JAMA
1.Ustaalioğlu İ, Kibici Ö. C-reactive protein to albumin ratio as a prognostic marker in community-acquired pneumonia mortality. TJCL. 2025;16:180–185.
MLA
Ustaalioğlu, İzzet, and Özge Kibici. “C-Reactive Protein to Albumin Ratio As a Prognostic Marker in Community-Acquired Pneumonia Mortality”. Turkish Journal of Clinics and Laboratory, vol. 16, no. 1, Mar. 2025, pp. 180-5, doi:10.18663/tjcl.1640626.
Vancouver
1.İzzet Ustaalioğlu, Özge Kibici. C-reactive protein to albumin ratio as a prognostic marker in community-acquired pneumonia mortality. TJCL. 2025 Mar. 1;16(1):180-5. doi:10.18663/tjcl.1640626