Combined Use of D-dimer and NLR as a Prognostic Index in COVID-19

Objective: We aimed to investigate the combined use of D-dimer and neutrophil-to-lymphocyte ratio (NLR) as a prognostic index-coronavirus disease (PRI-COVID) in COVID-19 patients to predict mortality.
Material and Methods: We included 152 COVID-19 patients in our cross-sectional study. The cut-off value of D-dimer to predict mortality was 1.07 μg/mL with a sensitivity of 68% and specificity of 80% [area under curve (AUC) ± SE: 0.752±0.05; positive predictive value (PPV) 39.5%, and negative predictive value (NPV) 92.7%; p<0.001]. Meanwhile, at a cut-off value of 3.83, the sensitivity and specificity of NLR in predicting mortality were 92% and 48.8%, respectively (AUC ± SE: 0.730±0.05; PPV: 26.1%; NPV: 96.9%; p<0.001). We categorized patients as low, moderate, and high risk using the PRI-COVID model (low risk: <1.07 D-dimer and <3.83 NLR; moderate risk: >1.07 D-dimer or >3.83 NLR; high risk: >1.07 D-dimer and NLR >3.83). High-risk PRI-COVID was associated with 6.37 times increased risk of death compared with the low/moderate risk group.
Results: Combined use of coagulation and inflammation parameters might can be associated with mortality.
Conclusion: Our results suggest that PRI-COVID is easy to assess and useful in predicting both 30-day and overall survival in patients with COVID-19.