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Value of the Neutrophil-Lymphocyte Ratio in Predicting COVID-19 Severity: A Meta-analysis
Ying Wang1, Jingyi Zhao2, Lan Yang3
1Department of Pharmacy, The Affiliated Hospital of Chengde Medical College, Chengde 067000, China.
Insights
The neutrophil-lymphocyte ratio (NLR) can accurately indicate the severity of Coronavirus disease 2019 (COVID-19). This finding aids in identifying severe COVID-19 cases for better clinical decisions.
Area of Science:
- Infectious Diseases
- Hematology
- Medical Diagnostics
Background:
- Coronavirus disease 2019 (COVID-19) is a highly contagious and rapidly spreading illness.
- Current laboratory techniques for determining COVID-19 severity are limited in simplicity and timeliness.
- The neutrophil-lymphocyte ratio (NLR) is investigated as a potential severity indicator.
Purpose of the Study:
- To assess the diagnostic performance of the neutrophil-lymphocyte ratio (NLR) in distinguishing severe from non-severe COVID-19 cases.
- To evaluate the NLR's potential as a simple and timely laboratory marker for COVID-19 severity.
Main Methods:
- A systematic meta-analysis was conducted on 30 studies comprising 5570 patients.
- Studies published between January 1, 2020, and July 1, 2021, were sourced from PubMed, EMBASE, and Cochrane Library.
- Statistical analyses included pooled sensitivity, specificity, likelihood ratios, diagnostic odds ratio (DOR), and area under the curve (AUC).
Main Results:
- The analysis included 1603 severe and 3967 non-severe COVID-19 cases.
- Overall sensitivity was 0.82 (95% CI, 0.77-0.87) and specificity was 0.77 (95% CI, 0.70-0.83).
- The diagnostic odds ratio (DOR) was 16 (95% CI, 10-24) and the area under the curve (AUC) was 0.87 (95% CI, 0.84-0.90).
Conclusions:
- The neutrophil-lymphocyte ratio (NLR) demonstrates significant accuracy in determining COVID-19 severity.
- NLR can serve as a valuable tool for identifying patients with severe COVID-19.
- This indicator can assist clinicians in making informed treatment decisions.
Background:
Coronavirus disease 2019 (COVID-19) is highly contagious and continues to spread rapidly. However, there are no simple and timely laboratory techniques to determine the severity of COVID-19. In this meta-analysis, we assessed the potential of the neutrophil-lymphocyte ratio (NLR) as an indicator of severe versus nonsevere COVID-19 cases.
Methods:
A search for studies on the NLR in severe and nonsevere COVID-19 cases published from January 1, 2020, to July 1, 2021, was conducted on the PubMed, EMBASE, and Cochrane Library databases. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR), and area under the curve (AUC) analyses were done on Stata 14.0 and Meta-disc 1.4 to assess the performance of the NLR.
Results:
Thirty studies, including 5570 patients, were analyzed. Of these, 1603 and 3967 patients had severe and nonsevere COVID-19, respectively. The overall sensitivity and specificity were 0.82 (95% confidence interval (CI), 0.77-0.87) and 0.77 (95% CI, 0.70-0.83), respectively; positive and negative correlation ratios were 3.6 (95% CI, 2.7-4.7) and 0.23 (95% CI, 0.17-0.30), respectively; DOR was 16 (95% CI, 10-24), and the AUC was 0.87 (95% CI, 0.84-0.90).
Conclusion:
The NLR could accurately determine the severity of COVID-19 and can be used to identify patients with severe disease to guide clinical decision-making.
