Identifying critically ill patients at risk of death from coronavirus disease

doi:10.5847/wjem.j.1920-8642.2021.01.003

Abstract

Abstract:

BACKGROUND: A pandemic of coronavirus disease (COVID-19) has been declared by the World Health Organization (WHO) and caring for critically ill patients is expected to be at the core of battling this disease. However, little is known regarding an early detection of patients at high risk of fatality.

METHODS: This retrospective cohort study recruited consecutive adult patients admitted between February 8 and February 29, 2020, to the three intensive care units (ICUs) in a designated hospital for treating COVID-19 in Wuhan. The detailed clinical information and laboratory results for each patient were obtained. The primary outcome was in-hospital mortality. Potential predictors were analyzed for possible association with outcomes, and the predictive performance of indicators was assessed from the receiver operating characteristic (ROC) curve.

RESULTS: A total of 121 critically ill patients were included in the study, and 28.9% (35/121) of them died in the hospital. The non-survivors were older and more likely to develop acute organ dysfunction, and had higher Sequential Organ Failure Assessment (SOFA) and quick SOFA (qSOFA) scores. Among the laboratory variables on admission, we identified 12 useful biomarkers for the prediction of in-hospital mortality, as suggested by area under the curve (AUC) above 0.80. The AUCs for three markers neutrophil-to-lymphocyte ratio (NLR), thyroid hormones free triiodothyronine (FT3), and ferritin were 0.857, 0.863, and 0.827, respectively. The combination of two easily accessed variables NLR and ferritin had comparable AUC with SOFA score for the prediction of in-hospital mortality (0.901 vs. 0.955, P=0.085).

CONCLUSIONS: Acute organ dysfunction combined with older age is associated with fatal outcomes in COVID-19 patients. Circulating biomarkers could be used as powerful predictors for the in-hospital mortality.

Key words: Coronavirus disease, Neutrophil-to-lymphocyte ratio, Mortality, Predictor

Wei Guo, Lin-yu Ran, Ji-hong Zhu, Qing-gang Ge, Zhe Du, Fei-long Wang, Wei-bo Gao, Tian-bing Wang. Identifying critically ill patients at risk of death from coronavirus disease[J]. World Journal of Emergency Medicine, 2021, 12(1): 18-23.

Figures/Tables 2

Table 1

Performance of variables for predicting in-hospital mortality in COVID-19 patients*

Variables	AUC	95% CI	Cut-off value	Sensitivity (%)	Specificity (%)	P
SOFA	0.960	0.908-0.987	2	94.29	93.02	<0.001
Free triiodothyronine	0.863	0.761-0.932	3.25 pmol/L	94.44	75.93	<0.001
Neutrophil-to-lymphocyte ratio	0.857	0.782-0.914	8.48	85.71	79.07	<0.001
Procalcitonin	0.850	0.771-0.910	0.38 ng/mL	84.85	76.54	<0.001
Neutrophil count	0.842	0.764-0.902	5.71×10⁹/L	82.86	77.91	<0.001
Prothrombin time	0.828	0.748-0.891	15.2 seconds	71.43	85.88	<0.001
White blood cell count	0.827	0.747-0.889	7.04×10⁹/L	85.71	70.93	<0.001
Ferritin	0.827	0.744-0.892	862.7 μg/L	94.12	58.44	<0.001
Direct bilirubin	0.826	0.746-0.889	5.2 μmol/L	80.00	74.12	<0.001
High sensitive C-reactive protein	0.824	0.742-0.889	131.1 mg/L	68.57	85.00	<0.001
Albumin	0.811	0.730-0.877	31.9 g/L	94.29	61.63	<0.001
High sensitive troponin I	0.808	0.722-0.877	33.4 ng/mL	73.53	86.84	<0.001
Total bilirubin	0.794	0.711-0.862	10.1 μmol/L	85.71	61.63	<0.001
Lactate dehydrogenase	0.794	0.710-0.862	425 U/L	77.14	76.74	<0.001
NT-proBNP	0.793	0.704-0.864	247 pg/mL	96.97	56.58	<0.001
Creatine kinase muscle brain isoenzyme	0.793	0.695-0.870	2.2 ng/mL	70.37	87.69	<0.001
Fibrin degradation products	0.792	0.701-0.866	8.9 μg/mL	81.25	69.01	<0.001
D-dimer	0.786	0.702-0.856	2.21 μg/mL	80.00	68.24	<0.001
Aspartate aminotransferase	0.763	0.677-0.836	33 U/L	88.57	60.47	<0.001
Blood urea nitrogen	0.761	0.675-0.834	5.2 μmol/L	91.43	56.98	<0.001
Lymphocyte count	0.734	0.646-0.811	0.65×10⁹/L	68.57	74.42	<0.001
qSOFA	0.734	0.646-0.810	0	97.14	32.56	<0.001
Myohemoglobin	0.726	0.622-0.814	87 ng/mL	77.78	60.94	<0.001
Interleukin-2 receptor	0.720	0.627-0.802	1,215 U/mL	73.53	64.47	<0.001
Glucose	0.717	0.626-0.797	6.39 mmol/L	77.14	65.43	<0.001
AT3	0.710	0.611-0.796	78%	45.16	87.14	<0.001
Free thyroxine	0.693	0.573-0.796	19.35 pmol/L	83.33	55.56	0.003
Alanine aminotransferase	0.677	0.586-0.759	50 U/L	42.86	88.37	0.001
Creatine kinase	0.664	0.569-0.750	207 U/L	53.57	84.88	0.012
Platelet count	0.650	0.558-0.734	239×10⁹/L	85.71	44.19	0.008
Age	0.626	0.534-0.712	56	88.57	31.40	0.021

Table 1

Figure 1.

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