Indian Journal of Respiratory Care

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VOLUME 11 , ISSUE 2 ( April-June, 2022 ) > List of Articles

Original Article

Risk Factors and a Novel Score (CARI-65) Predicting Mortality in COVID-19 Patients

Suhail Mantoo, Afshan Shabir, Umar Hafiz Khan, Tajamul Hussain Shah, Farhana Siraj, Nazia Mehfooz, Muzaffar Bindroo, Syed Mudasir Qadri, Ajaz Nabi Koul, Mushtaq Ahmad, Fayaz Ahmad Sofi, Sonaullah Shah, Rafi Ahmed Jan, Asma Shah, Faizan Wani

Keywords : Mortality in coronavirus disease 2019, mortality score in coronavirus disease 2019, predictors of mortality

Citation Information : Mantoo S, Shabir A, Khan UH, Shah TH, Siraj F, Mehfooz N, Bindroo M, Qadri SM, Koul AN, Ahmad M, Sofi FA, Shah S, Jan RA, Shah A, Wani F. Risk Factors and a Novel Score (CARI-65) Predicting Mortality in COVID-19 Patients. Indian J Respir Care 2022; 11 (2):154-161.

DOI: 10.4103/ijrc.ijrc_3_22

License: CC BY-NC-SA 4.0

Published Online: 06-12-2022

Copyright Statement:  Copyright © 2022; Indian Journal of Respiratory Care.


Purpose: The rapid spread of severe acute respiratory syndrome coronavirus-2 infection resulted in an exponential increase in hospitalizations and mortality. We aimed to explore the determinants of mortality and formulate a score that can predict mortality in patients hospitalized due to coronavirus disease 2019 (COVID-19). Materials and Methods: In this retrospective study, 1024 COVID-19 patients hospitalized between March 2020 and October 2020 were included. Patient demographics, underlying comorbid illnesses, clinical features, vital signs at admission, disease severity, and laboratory parameters, were collected from hospital medical records and analyzed to derive risk factors for in-hospital mortality and formulate a mortality prediction score. Results: The median age of the study population was 56 years (interquartile range [IQR], 45-65) and was significantly higher in nonsurvivors than in survivors (62 [IQR 55-70] vs. 52 [IQR 40-65]; P = 0.001). Hypertension and diabetes were the most common associated comorbid illnesses seen in 50.5% (n = 518) and 29.1% (n = 299) of patients, respectively. The presence of altered level of consciousness (C), azotemia with serum creatinine > 1.5 mg/dl (A), respiratory rate > 25/min (R), interleukin-6 > 25 pg/ml (I), and age <65 years were independent predictors of mortality. A six-point COVID-19 mortality prediction score, “CARI-65,” was developed using variables predicting mortality in multivariate regression analysis. The CARI-65 score <3 had a sensitivity and specificity of 87.1% and 57.3%, respectively, and positive and negative predictive values of 42.52% and 92.45%, respectively, in predicting mortality. Conclusion: This study demonstrated various demographic, clinical, and laboratory parameters that predict mortality in hospitalized COVID-19 patients. We also proposed a simple risk stratification score to predict mortality in hospitalized COVID-19 patients, so that effective triaging of patients can be done to utilize health-care resources efficiently.

  1. WHO Director-General's Opening Remarks at the Media Briefing on COVID-19. World Health Organization. Available from: opening-remarks-at-the-media-briefing-on-covid-19-11- March-2020. [Last accessed on 25 Dec 2021].
  2. WHO Coronavirus Disease (COVID-19) Dashboard. Available from: [Last accessed on 2021 Dec 24].
  3. Siddiqui SH, Sarfraz A, Rizvi A, Shaheen F, Yousafzai MT, Ali SA. Global variation of COVID-19 mortality rates in the initial phase. Osong Public Health Res Perspect 2021;12:64-72.
  4. COVID Tracking India. Available from: [Last accessed on 2021 Dec 24].
  5. Suresh S, Tiwari A, Mathew R, Bhaskararayuni J, Sahu AK, Aggarwal P, et al. Predictors of mortality and the need of mechanical ventilation in confirmed COVID-19 patients presenting to the emergency department in North India. J Family Med Prim Care 2021;10:542-9.
  6. Jain AC, Kansal S, Sardana R, Bali RK, Kar S, Chawla R. A retrospective observational study to determine the early predictors of in-hospital mortality at admission with COVID-19. Indian J Crit Care Med 2020;24:1174-9.
  7. Mahendra M, Nuchin A, Kumar R, Shreedhar S, Mahesh PA. Predictors of mortality in patients with severe COVID-19 pneumonia - A retrospective study. Adv Respir Med 2021;89:135-44.
  8. Clinical Management of COVID-19: Interim Guidance. World Health Organization. Available from: [Last accessed on 2020 May 27].
  9. Richardson S, Hirsch JS, Narasimhan M, Crawford JM, McGinn T, Davidson KW, et al. Presenting characteristics, comorbidities, and outcomes among 5700 patients hospitalized with COVID-19 in the New York City Area. JAMA 2020;323:2052-9.
  10. Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China. JAMA 2020;323:1061-9.
  11. Grasselli G, Greco M, Zanella A, Albano G, Antonelli M, Bellani G, et al. Risk factors associated with mortality among patients with COVID-19 in Intensive Care Units in Lombardy, Italy. JAMA Intern Med 2020;180:1345-55.
  12. Quah P, Li A, Phua J. Mortality rates of patients with COVID-19 in the Intensive Care Unit: A systematic review of the emerging literature. Crit Care 2020;24:285.
  13. Olivas-Martínez A, Cárdenas-Fragoso JL, Jiménez JV, Lozano-Cruz OA, Ortiz-Brizuela E, Tovar-Méndez VH, et al. In-hospital mortality from severe COVID-19 in a tertiary care center in Mexico City; causes of death, risk factors and the impact of hospital saturation. PLoS One 2021;16:e0245772.
  14. Wang Y, Lu X, Li Y, Chen H, Chen T, Su N, et al. Clinical course and outcomes of 344 intensive care patients with COVID-19. Am J Respir Crit Care Med 2020;201:1430-4.
  15. King CS, Sahjwani D, Brown AW, Feroz S, Cameron P, Osborn E, et al. Outcomes of mechanically ventilated patients with COVID-19 associated respiratory failure. PLoS One 2020;15:e0242651.
  16. Radovanovic D, Coppola S, Franceschi E, Gervasoni F, Duscio E, Chiumello DA, et al. Mortality and clinical outcomes in patients with COVID-19 pneumonia treated with non-invasive respiratory support: A rapid review. J Crit Care 2021;65:1-8.
  17. Parohan M, Yaghoubi S, Seraji A, Javanbakht MH, Sarraf P, Djalali M. Risk factors for mortality in patients with Coronavirus disease 2019 (COVID-19) infection: A systematic review and meta-analysis of observational studies. Aging Male 2020;23:1416-24.
  18. Ciceri F, Castagna A, Rovere-Querini P, De Cobelli F, Ruggeri A, Galli L, et al. Early predictors of clinical outcomes of COVID-19 outbreak in Milan, Italy. Clin Immunol 2020;217:108509.
  19. Santos MM, Lucena EE, Lima KC, Brito AA, Bay MB, Bonfada D. Survival and predictors of deaths of patients hospitalised due to COVID-19 from a retrospective and multicentre cohort study in Brazil. Epidemiol Infect 2020;148:e198.
  20. Acharya D, Lee K, Lee DS, Lee YS, Moon SS. Mortality rate and predictors of mortality in hospitalized COVID-19 patients with diabetes. Healthcare (Basel) 2020;8:338.
  21. Moledina SM, Maini AA, Gargan A, Harland W, Jenney H, Phillips G, et al. Clinical characteristics and predictors of mortality in patients with COVID-19 infection outside intensive care. Int J Gen Med 2020;13:1157-65.
  22. Chilimuri S, Sun H, Alemam A, Mantri N, Shehi E, Tejada J, et al. Predictors of mortality in adults admitted with COVID-19: Retrospective cohort study from New York City. West J Emerg Med 2020;21:779-84.
  23. Kenerly MJ, Shah P, Patel H, Racine R, Jani Y, Owens C, et al. Altered mental status is an independent predictor of mortality in hospitalized COVID-19 patients. Ir J Med Sci 2022;191:21-6.
  24. Khamis F, Memish Z, Bahrani MA, Dowaiki SA, Pandak N, Bolushi ZA, et al. Prevalence and predictors of in-hospital mortality of patients hospitalized with COVID-19 infection. J Infect Public Health 2021;14:759-65.
  25. Du RH, Liang LR, Yang CQ, Wang W, Cao TZ, Li M, et al. Predictors of mortality for patients with COVID-19 pneumonia caused by SARSCoV-2: A prospective cohort study. Eur Respir J 2020;55:2000524.
  26. Opal SM, Girard TD, Ely EW. The immunopathogenesis of sepsis in elderly patients. Clin Infect Dis 2005;41 Suppl 7:S504-12.
  27. Tian W, Jiang W, Yao J, Nicholson CJ, Li RH, Sigurslid HH, et al. Predictors of mortality in hospitalized COVID-19 patients: A systematic review and meta-analysis. J Med Virol 2020;92:1875-83.
  28. Mehraeen E, Karimi A, Barzegary A, Vahedi F, Afsahi AM, Dadras O, et al. Predictors of mortality in patients with COVID-19 - A systematic review. Eur J Integr Med 2020;40:101226.
  29. Rahim F, Amin S, Noor M, Bahadur S, Gul H, Mahmood A, et al. Mortality of patients with severe COVID-19 in the Intensive Care Unit: An observational study from a major COVID-19 receiving hospital. Cureus 2020;12:e10906.
  30. Mao L, Jin H, Wang M, Hu Y, Chen S, He Q, et al. Neurologic manifestations of hospitalized patients with coronavirus disease 2019 in Wuhan, China. JAMA Neurol 2020;77:683-90.
  31. Chachkhiani D, Soliman MY, Barua D, Isakadze M, Villemarette-Pittman NR, Devier DJ, et al. Neurological complications in a predominantly African American sample of COVID-19 predict worse outcomes during hospitalization. Clin Neurol Neurosurg 2020;197:106173.
  32. Lim WS, van der Eerden MM, Laing R, Boersma WG, Karalus N, Town GI, et al. Defining community acquired pneumonia severity on presentation to hospital: An international derivation and validation study. Thorax 2003;58:377-82.
  33. Fine MJ, Auble TE, Yealy DM, Hanusa BH, Weissfeld LA, Singer DE, et al. A prediction rule to identify low-risk patients with communityacquired pneumonia. N Engl J Med 1997;336:243-50.
  34. Chatterjee NA, Jensen PN, Harris AW, Nguyen DD, Huang HD, Cheng RK, et al. Admission respiratory status predicts mortality in COVID-19. Influenza Other Respir Viruses 2021;15:569-72.
  35. Aksel G, İslam MM, Algın A, Eroğlu SE, Yaşar GB, Ademoğlu E, et al. Early predictors of mortality for moderate to severely ill patients with Covid-19. Am J Emerg Med 2021;45:290-6.
  36. Mendes A, Serratrice C, Herrmann FR, Genton L, Périvier S, Scheffler M, et al. Predictors of in-hospital mortality in older patients with COVID-19: The COVIDAge Study. J Am Med Dir Assoc 2020;21:1546-54.e3.
  37. Rastad H, Karim H, Ejtahed HS, Tajbakhsh R, Noorisepehr M, Babaei M, et al. Risk and predictors of in-hospital mortality from COVID-19 in patients with diabetes and cardiovascular disease. Diabetol Metab Syndr 2020;12:57.
  38. Sun X, Wang T, Cai D, Hu Z, Chen J, Liao H, et al. Cytokine storm intervention in the early stages of COVID-19 pneumonia. Cytokine Growth Factor Rev 2020;53:38-42.
  39. Herold T, Jurinovic V, Arnreich C, Lipworth BJ, Hellmuth JC, von Bergwelt-Baildon M, et al. Elevated levels of IL-6 and CRP predict the need for mechanical ventilation in COVID-19. J Allergy Clin Immunol 2020;146:128-36.e4.
  40. Zeng F, Huang Y, Guo Y, Yin M, Chen X, Xiao L, et al. Association of inflammatory markers with the severity of COVID-19: A meta-analysis. Int J Infect Dis 2020;96:467-74.
  41. Hunter CA, Jones SA. IL-6 as a keystone cytokine in health and disease. Nat Immunol 2015;16:448-57.
  42. Guaraldi G, Meschiari M, Cozzi-Lepri A, Milic J, Tonelli R, Menozzi M, et al. Tocilizumab in patients with severe COVID-19: A retrospective cohort study. Lancet Rheumatol 2020;2:e474-84.
  43. Sabaka P, Koščálová A, Straka I, Hodosy J, Lipták R, Kmotorková B, et al. Role of interleukin 6 as a predictive factor for a severe course of Covid-19: Retrospective data analysis of patients from a long-term care facility during Covid-19 outbreak. BMC Infect Dis 2021;21:308.
  44. Velavan TP, Meyer CG. Mild versus severe COVID-19: Laboratory markers. Int J Infect Dis 2020;95:304-7.
  45. Liu T, Zhang J, Yang Y, Ma H, Li Z, Zhang J, et al. The role of interleukin-6 in monitoring severe case of coronavirus disease 2019. EMBO Mol Med 2020;12:e12421.
  46. Ulhaq ZS, Soraya GV. Interleukin-6 as a potential biomarker of COVID-19 progression. Med Mal Infect 2020;50:382-3.
  47. Aziz M, Fatima R, Assaly R. Elevated interleukin-6 and severe COVID-19: A meta-analysis. J Med Virol 2020;92:2283-5.
  48. Mandel M, Harari G, Gurevich M, Achiron A. Cytokine prediction of mortality in COVID19 patients. Cytokine 2020;134:155190.
  49. Giamarellos-Bourboulis EJ, Netea MG, Rovina N, Akinosoglou K, Antoniadou A, Antonakos N, et al. Complex immune dysregulation in COVID-19 patients with severe respiratory failure. Cell Host Microbe 2020;27:992-1000.e3.
  50. Magro G. SARS-CoV-2 and COVID-19: Is interleukin-6 (IL-6) the ‘culprit lesion’ of ARDS onset? What is there besides Tocilizumab? SGP130Fc. Cytokine X 2020;2:100029.
  51. Simadibrata DM, Calvin J, Wijaya AD, Ibrahim NA. Neutrophil-tolymphocyte ratio on admission to predict the severity and mortality of COVID-19 patients: A meta-analysis. Am J Emerg Med 2021;42:60-9.
  52. Chen HL, Yan WM, Chen G, Zhang XY, Zeng ZL, Wang XJ, et al. CAPRL scoring system for prediction of 30-day mortality in 949 patients with coronavirus disease 2019 in Wuhan, China: A retrospective, observational study. Infect Dis Immunity 2021;1:28-35.
  53. Gue YX, Tennyson M, Gao J, Ren S, Kanji R, Gorog DA. Development of a novel risk score to predict mortality in patients admitted to hospital with COVID-19. Sci Rep 2020;10:21379.
  54. Altschul DJ, Unda SR, Benton J, de la Garza Ramos R, Cezayirli P, Mehler M, et al. A novel severity score to predict inpatient mortality in COVID-19 patients. Sci Rep 2020;10:16726.
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