Evaluation of the ability of the C-reactive protein-to-albumin ratio to predict short-term mortality in patients with COVID-19

Serdar Özdemir 1 * , Abdullah Algin 1 2
More Detail
1 University of Health Sciences Turkey, Ümraniye Training and Research Hospital, Clinic of Emergency Medicine, İstanbul, Turkey
2 University of Health Sciences Turkey, Somalia Mogadishu Recep Tayyip Erdogan Faculty of Health Sciences, Mogadishu, Somalia
* Corresponding Author
J CLIN MED KAZ, Volume 18, Issue 6, pp. 35-39. https://doi.org/10.23950/jcmk/11324
Download Full Text (PDF)


This study aimed to determine the ability of the C-reactive protein (CRP)-to-albumin ratio (CAR) to predict short-term mortality in patients with COVID-19.
Material and methods
This retrospective, observational, cohort study included patients with COVID-19. The patients’ demographics, clinical characteristics, CRP, albumin, CAR, blood urea nitrogen, creatinine, Troponin I and all-cause mortality within 30 days after admission were noted. The receiver operating characteristic curve analysis was performed, and odds ratios were calculated to determine the discriminative ability of the parameters.
A total of 103 patients with a median of age of 57 (20-92) years were included in the study. The rate of 30-day mortality was 4.8% for the study cohort. According to the best Youden’s index, the cut-off value for CRP was determined as 7 (sensitivity: 80%, specificity: 78.6%), and the area under curve (AUC) value was 0.801 (95% confidence interval: 71.1-87.3). According to the best Youden’s index, the cut-off value for CAR was 0.18 (sensitivity: 80%, specificity: 78.6%), and the area under curve (AUC) value was 0.806 (95% confidence interval: 71.6-87.7). There was no statistically significant difference between the AUC values of CRP and CAR (DeLong equality test, p = 0.938). The odds ratios of CRP (>7 mg/L) and CAR (>0.18) for 30-day mortality were 14.667 (95% confidence interval: 1.555-138.299) and 13.818 (95% confidence interval: 1.468-130.076), respectively.
CAR was not useful in predicting 30-day mortality in patients with COVID-19. The calculation of CAR rather than CRP had no clinically significant contribution to the prediction of 30-day mortality in this patient group.


Özdemir S, Algin A. Evaluation of the ability of the C-reactive protein-to-albumin ratio to predict short-term mortality in patients with COVID-19. J CLIN MED KAZ. 2021;18(6):35-9. https://doi.org/10.23950/jcmk/11324


  • Eroglu SE, Aksel G, Altunok I, et al. Can Google® trends predict emergency department admissions in pandemic periods? Medicine Science. 2021;10(1):111-117. https://doi.org/10.5455/medscience.2020.08.162
  • Sert E, Mutlu H, Kokulu K, Sarıtaş A. Anxiety Levels and Associated Factors Among Emergency Department Personnel Fighting COVID-19. J Contemp Med. 2020; 10(4): 556-561. https://doi.org/10.16899/jcm.972664
  • Zhou B, Kojima S, Kawamoto A, et al. COVID-19 pathogenesis, prognostic factors, and treatment strategy: Urgent recommendations. J Med Virol. 2021;93(5):2694-2704. https://doi.org/10.1002/jmv.26754.
  • Gallo Marin B, Aghagoli G, Lavine K, et al. Predictors of COVID-19 severity: A literature review. Rev Med Virol. 2021;31(1):1-10. https://doi.org/10.1002/rmv.2146.
  • Özdemir S, Eroğlu SE, Algın A, et al. Analysis of laboratory parameters in patients with COVID-19: Experiences from a pandemic hospital. Ann Clin Anal Med. 2021;12 (Supp 4):518-523. https://doi.org/10.4328/ACAM.20678
  • Aksel G, İslam MM, Algın A, et al. Early predictors of mortality for moderate to severely ill patients with Covid-19. Am J Emerg Med. 2021;45:290-296. https://doi.org/10.1016/j.ajem.2020.08.076.
  • Seyit M, Avci E, Nar R, et al. Neutrophil to lymphocyte ratio, lymphocyte to monocyte ratio and platelet to lymphocyte ratio to predict the severity of COVID-19. Am J Emerg Med. 2021;40:110-114. https://doi.org/10.1016/j.ajem.2020.11.058
  • Avramovski P, Avramovska M, Sotiroski K, Sikole A. Acute-phase proteins as promoters of abdominal aortic calcification in chronic dialysis patients. Saudi J Kidney Dis Transpl. 2019;30(2):376-386. https://doi.org/10.4103/1319-2442.256845.
  • Hanley JA, McNeil BJ. The meaning and use of the area under a receiver operating characteristic (ROC) curve. Radiology. 1982;143(1):29-36. https://doi.org/10.1148/radiology.143.1.7063747.
  • Hanley JA, McNeil BJ. A method of comparing the areas under receiver operating characteristic curves derived from the same cases. Radiology. 1983;148(3):839-43. https://doi.org/10.1148/radiology.148.3.6878708.
  • Deeks JJ. Systematic reviews of evaluations of diagnostic and screening tests. Egger M Davey Smith G Altman DG eds. Systematic reviews in health care: meta-analysis in context. Systematic reviews, 2nd ed 2001:248-282 BMJ Books London.
  • Price CP, Newall RG, Boyd JC. Use of protein: creatinine ratio measurements on random urine samples for prediction of significant proteinuria: a systematic review. Clin Chem. 2005;51(9):1577-86. https://doi.org/10.1373/clinchem.2005.049742.
  • Fischer JE, Bachmann LM, Jaeschke R. A readers' guide to the interpretation of diagnostic test properties: clinical example of sepsis. Intensive Care Med. 2003;29(7):1043-51. https://doi.org/10.1007/s00134-003-1761-8.
  • Özdemir S, Akça HŞ, Algın A, et al. Can C-reactive protein-to-albumin ratio be a predictor of short-term mortality in community-acquired pneumonia? Ann Clin Anal Med. 2021;12(9):1043-1048. https://doi.org/ 10.4328/ACAM.20576.
  • Acet H, Güzel T, Aslan B, et al. Predictive Value of C-Reactive Protein to Albumin Ratio in ST-Segment Elevation Myocardial Infarction Patients Treated with Primary Percutaneous Coronary Intervention. Angiology. 2021;72(3):244-251. https://doi.org/10.1177/0003319720963697.
  • Karakoyun I, Colak A, Turken M, et al. Diagnostic utility of C-reactive protein to albumin ratio as an early warning sign in hospitalized severe COVID-19 patients. Int Immunopharmacol. 2021;91:107285. https://doi.org/10.1016/j.intimp.2020.107285.
  • Güney BÇ, Taştan YÖ, Doğantekin B, et al. Predictive Value of CAR for In-Hospital Mortality in Patients with COVID-19 Pneumonia: A Retrospective Cohort Study. Arch Med Res. 2021;52(5):554-560. https://doi.org/10.1016/j.arcmed.2021.02.006.
  • El-Shabrawy M, Alsadik M, El-Shafei M, et al. Interleukin-6 and C-reactive protein/albumin ratio as predictors of COVID-19 severity and mortality. The Egyptian Journal of Bronchology. 2021;15(1). https://doi.org/10.1186/s43168-021-00054-1
  • Paliogiannis P, Zinellu A, Scano V, et al. Laboratory test alterations in patients with COVID-19 and non-COVID-19 interstitial pneumonia: a preliminary report. J Infect Dev Ctries. 2020;14(7):685-690. https://doi.org/10.3855/jidc.12879.