A novel combined index of D-dimer, fibrinogen, albumin, and platelet (FDAPR) as mortality predictor of COVID-19.

Background: In coronavirus disease 2019 (COVID-19) caused by SARSCoV2 viruses, coagulation abnormalities are strongly correlated between disease severity and mortality risk.

Aims: The aim was to search for new indices to determine mortality risk. Fibrinogen times D-dimer to albumin times platelet ratio calculated with the formula (FDAPR index: ((Fibrinogen × D-dimer)/(Albumin × Platelet)) investigated as a mortality marker in COVID-19 patients. The hospitalization data of 1124 patients were analyzed from the electronic archive system. Hemogram, coagulation, and inflammatory markers were investigated in the study group.

Materials And Methods: All statistical analyses like the student t-test, Mann-Whitney U, Kaplan-Meier, and Cox hazard ratio, were performed with the SPSS 22.0 program.

Results: Prothrombin time was prolonged significantly in patients (P < 0.05) compared to healthy subjects (n = 30). D-dimer and fibrinogen were high, and albumin and platelet counts were low in COVID-19 patients (all, P < 0.001). When the data of 224 non-survivors and 900 survived patients were compared, D-dimer and fibrinogen were higher, and albumin and platelet lower (all, P < 0.001) compared to mild and severe patients. At the cut-off value of 0.49, the FDAPR index was performed with 89.1% sensitivity and 88.6% specificity. FDAPR index had the highest mortality predictive power (P < 0.01; HR = 5.366; 95% CI; 1.729-16.654).

Conclusions: This study revealed that the FDAPR index could be used as a mortality marker of COVID-19 disease.