Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Sep;56(3):106110.
doi: 10.1016/j.ijantimicag.2020.106110. Epub 2020 Jul 23.

Diagnostic performance of initial blood urea nitrogen combined with D-dimer levels for predicting in-hospital mortality in COVID-19 patients

Anying Cheng  1 , Liu Hu  2 , Yiru Wang  1 , Luyan Huang  3 , Lingxi Zhao  2 , Congcong Zhang  2 , Xiyue Liu  2 , Ranran Xu  1 , Feng Liu  4 , Jinping Li  5 , Dawei Ye  6 , Tao Wang  7 , Yongman Lv  8 , Qingquan Liu  9
Affiliations

Diagnostic performance of initial blood urea nitrogen combined with D-dimer levels for predicting in-hospital mortality in COVID-19 patients

Anying Cheng et al. Int J Antimicrob Agents. 2020 Sep.

Abstract

The crude mortality rate in critical pneumonia cases with coronavirus disease 2019 (COVID-19) reaches 49%. This study aimed to test whether levels of blood urea nitrogen (BUN) in combination with D-dimer were predictors of in-hospital mortality in COVID-19 patients. The clinical characteristics of 305 COVID-19 patients were analysed and were compared between the survivor and non-survivor groups. Of the 305 patients, 85 (27.9%) died and 220 (72.1%) were discharged from hospital. Compared with discharged cases, non-survivor cases were older and their BUN and D-dimer levels were significantly higher (P < 0.0001). Least absolute shrinkage and selection operator (LASSO) and multivariable Cox regression analyses identified BUN and D-dimer levels as independent risk factors for poor prognosis. Kaplan-Meier analysis showed that elevated levels of BUN and D-dimer were associated with increased mortality (log-rank, P < 0.0001). The area under the curve for BUN combined with D-dimer was 0.94 (95% CI 0.90-0.97), with a sensitivity of 85% and specificity of 91%. Based on BUN and D-dimer levels on admission, a nomogram model was developed that showed good discrimination, with a concordance index of 0.94. Together, initial BUN and D-dimer levels were associated with mortality in COVID-19 patients. The combination of BUN ≥ 4.6 mmol/L and D-dimer ≥ 0.845 μg/mL appears to identify patients at high risk of in-hospital mortality, therefore it may prove to be a powerful risk assessment tool for severe COVID-19 patients.

Keywords: Blood urea nitrogen; COVID-19; D-dimer; Viral pneumonia.

PubMed Disclaimer

Figures

Fig 1
Fig. 1
The prognostic factors of blood urea nitrogen (BUN) and D-dimer were selected by least absolute shrinkage and selection operator (LASSO) regression analyses. (A) LASSO coefficient profiles of the non-zero variables of COVID-19. A coefficient profile plot was produced against the log (λ) sequence. A vertical line was drawn at the value selected using 10-fold cross-validation, where optimal λ resulted in three non-zero coefficients. (B) Mean-squared error plot of the lowest point of the red curve, which corresponds to a three-variable model. Tuning parameter (λ) selection in the LASSO model used 10-fold cross-validation via minimum criteria. The mean-squared error was plotted versus log (λ). Dotted vertical lines were drawn at the optimal values by using the minimum criteria and the 1 standard error (SE) of the minimum criteria (the 1-SE criteria). A λ value of 0.114, with log (λ) –2.172 was chosen (1-SE criteria) according to 10-fold cross-validation.
Fig 2
Fig. 2
Kaplan–Meier survival estimates according to blood urea nitrogen (BUN) and D-dimer levels. (A) Risk group stratification with the median of BUN concentration (4.6 mmol/L). (B) Risk group stratification with the median of D-dimer concentration (0.845 μg/mL). (C) Stratification with BUN and D-dimer.
Fig 3
Fig. 3
Receiver operating characteristic curves for in-hospital mortality. The AUC increased significantly when BUN and D-dimer levels were combined. CI, confidence interval.
Fig 4
Fig. 4
(A) Nomogram predicting mortality of patients with COVID-19. (B) Calibration plot of the nomogram for patients with COVID-19.
See this image and copyright information in PMC

References

    1. Phelan AL, Katz R, Gostin LO. The novel coronavirus originating in Wuhan, China: challenges for global health governance. JAMA. 2020 Jan 30 doi: 10.1001/jama.2020.1097. [Epub ahead of print] - DOI - PubMed
    1. Wang LS, Wang YR, Ye DW, Liu QQ. Review of the 2019 novel coronavirus (SARS-CoV-2) based on current evidence. Int J Antimicrob Agents. 2020;55 doi: 10.1016/j.ijantimicag.2020.105948. - DOI - PMC - PubMed
    1. Wu Z, McGoogan JM. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: summary of a report of 72 314 cases from the Chinese Center for Disease Control and Prevention. JAMA. 2020 Feb 24 doi: 10.1001/jama.2020.2648. [Epub ahead of print] - DOI - PubMed
    1. Kazory A. Emergence of blood urea nitrogen as a biomarker of neurohormonal activation in heart failure. Am J Cardiol. 2010;106:694–700. - PubMed
    1. Yang CJ, Chen J, Phillips AR, Windsor JA, Petrov MS. Predictors of severe and critical acute pancreatitis: a systematic review. Dig Liver Dis. 2014;46:446–451. - PubMed

MeSH terms