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Simple Parameters from Complete Blood Count Predict In-Hospital Mortality in COVID-19
Mattia Bellan1,2, Danila Azzolina1, Eyal Hayden1,2
1Università del Piemonte Orientale UPO, Novara, Italy.
Insights
Complete blood count parameters like red cell distribution width (RDW) and neutrophil-to-lymphocyte (NL) ratio can predict COVID-19 mortality. Higher RDW and NL ratio indicate increased risk, while higher platelet count suggests a protective effect.
Area of Science:
- Hematology
- Infectious Diseases
- Clinical Pathology
Background:
- Coronavirus Disease 2019 (COVID-19) presents a wide spectrum of clinical severity.
- Identifying predictors of poor prognosis is crucial for effective patient management and therapeutic strategies.
- Complete blood count (CBC) is a readily available laboratory tool.
Purpose of the Study:
- To evaluate the prognostic value of CBC parameters in hospitalized COVID-19 patients.
- To identify specific CBC markers that predict in-hospital mortality.
Main Methods:
- Retrospective analysis of 664 patients hospitalized with COVID-19.
- Collection of demographic data and complete blood cell counts.
- Recording of in-hospital outcomes (mortality or discharge).
Main Results:
- Red cell distribution width (RDW), neutrophil-to-lymphocyte (NL) ratio, and platelet count significantly predicted in-hospital mortality.
- Age and gender were also strong predictors of mortality.
- Specific cut-offs identified: NL ratio > 4.68 (OR 3.40), RDW > 13.7% (OR 4.09), and platelet count > 166,000/μL (OR 0.45, protective).
Conclusions:
- Simple laboratory parameters from CBC can stratify COVID-19 severity.
- These findings support the use of CBC for guiding clinical decisions in COVID-19 patient monitoring and treatment.
- RDW, NL ratio, and platelet count offer valuable prognostic information.
Introduction:
The clinical course of Coronavirus Disease 2019 (COVID-19) is highly heterogenous, ranging from asymptomatic to fatal forms. The identification of clinical and laboratory predictors of poor prognosis may assist clinicians in monitoring strategies and therapeutic decisions.
Materials And Methods:
In this study, we retrospectively assessed the prognostic value of a simple tool, the complete blood count, on a cohort of 664 patients (F 260; 39%, median age 70 (56-81) years) hospitalized for COVID-19 in Northern Italy. We collected demographic data along with complete blood cell count; moreover, the outcome of the hospital in-stay was recorded.
Results:
At data cut-off, 221/664 patients (33.3%) had died and 453/664 (66.7%) had been discharged. Red cell distribution width (RDW) (χ 2 10.4; p < 0.001), neutrophil-to-lymphocyte (NL) ratio (χ 2 7.6; p = 0.006), and platelet count (χ 2 5.39; p = 0.02), along with age (χ 2 87.6; p < 0.001) and gender (χ 2 17.3; p < 0.001), accurately predicted in-hospital mortality. Hemoglobin levels were not associated with mortality. We also identified the best cut-off for mortality prediction: a NL ratio > 4.68 was characterized by an odds ratio for in-hospital mortality (OR) = 3.40 (2.40-4.82), while the OR for a RDW > 13.7% was 4.09 (2.87-5.83); a platelet count > 166,000/μL was, conversely, protective (OR: 0.45 (0.32-0.63)).
Conclusion:
Our findings arise the opportunity of stratifying COVID-19 severity according to simple lab parameters, which may drive clinical decisions about monitoring and treatment.
