Platelet-Lymphocyte Ratio Dynamics and Severity Correlation in COVID-19: Insights from Platelet Count Variations
DOI:
https://doi.org/10.52206/jsmc.2025.15.1.1000Abstract
Background: COVID-19, driven by the novel β-Coronavirus, significantly affects hematological parameters. Platelet count, Platelet-Lymphocyte and Neutrophil-Lymphocyte Ratios have been recommended as potential signs of disease severity. This study aimed to evaluate the relationship between platelet count, PLR, and the severity of COVID-19 in hospitalized patients.
Objective: To assess the association of Platelet-Lymphocyte Ratios, platelet count, and disease severity in hospitalized COVID-19 patients and determine their potential as prognostic markers.
Materials and Methods: In this prospective study, 66 hospitalized COVID-19 patients were included. Diagnosis was confirmed through PCR or high-resolution CT scans. Exclusion criteria included bacterial or other viral infections. Hematological parameters, including platelet count, PLR, NLR, and absolute lymphocyte count, were measured at admission and during hospitalization. Data analysis was conducted using SPSS version 20, employing descriptive statistics, chi-square tests, ROC curve analysis, and Cox regression as well.
Results: The study population consisted of 41 males (62%) and 25 females (38%), with an average age of 60 years.The mean platelet count was 273.85 ± 108.53 x 10^9/L, and the mean PLR was 318.90 ± 162.64. ROC curve analysis showed that platelet count and PLR predicted favorable outcomes (AUC 0.661 and 0.574), while NLR and lymphocyte count predicted poor outcomes (AUC 0.821 and 0.506). Cox regression revealed a significant association between NLR and mortality (HR 1.052, p < 0.05).
Conclusion: Platelet count and PLR serve as valuable indicators for predicting COVID-19 consequences using lower platelet counts and higher PLR indicating more severe disease. NLR shows a strong correlation with deaths and may serve as a crucial predictor of severe COVID-19 cases.
Keywords: COVID-19, Cytokine storm, Lymphocytes, Platelets, Severity.
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