Elucidating the Correlation of D-Dimer Levels with COVID-19 Severity: A Scoping Review

Abstract

Aims. The review explores the findings of previous studies to elucidate the association between levels of D-dimer and COVID-19 severity and prognosis. In addition, we assessed the efficiency of anticoagulant therapies in reducing COVID-19 severity and improving the prognosis of the patients. Materials and Methods. A comprehensive literature review was conducted using MEDLINE/PubMed databases, Scopus, and Web of Science with the help of keywords “COVID-19,” “D-Dimer,” “Thrombosis,” “Fibrin network,” “Anticoagulant therapy,” “Inflammation,” and “disease severity.” Based on all these articles and clinical experience, a scoping review was constructed and the full texts of the articles that were retrieved were accessed. Results. A D-dimer is a complex protein molecule that is formed during plasmin-mediated degradation of the fibrin network. Thus, it serves as a marker of thrombotic activity. On the other hand, in addition to severe respiratory distress and reduction in pulmonary gas exchange, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) also triggers prothrombotic changes in the infected individuals. The levels of D-dimer have been postulated to be positively associated with the degree of disease severity among COVID-19 patients. Conclusions. It has been postulated that D-dimer could potentially be used as a biomarker to predict the prognosis and outcome of COVID-19 patients at the time of admission to hospitals and facilitate more personalized and efficient clinical management that could significantly reduce the mortality rate of such patients and allow more rapid recovery.

Discrepancy between biomarkers of lung injury and 1‐year mortality in COVID‐19

“…11 Several retrospective studies report that d-dimer levels are associated with the disease severity and mortality in COVID-19. 12 The hallmark of the lung damage in COVID19 is intraalveolar fibrin deposition. d-dimer is a protein degradation product of fibrin that is formed by plasmin during fibrinolysis.…”

“…Observational studies report that the lungs are the potential sources of d-dimer in COVID-19. [11][12][13] A retrospective study from Wuhan, China reports the COVID-19 outcome from 676 laboratory-confirmed cases. The study comes from the first wave of the pandemic.…”

“…Several retrospective studies report that d ‐dimer levels are associated with the disease severity and mortality in COVID‐19. 12 …”

“…d ‐dimer is a protein degradation product of fibrin that is formed by plasmin during fibrinolysis. 12 d ‐dimer serves as an indirect biomarker of thrombosis. Fibrinolysis and proteolytic breakdown of the fibrin in the capillary beds of the lung segments increase the d ‐dimer levels in the circulation.…”

“…Observational studies report that the lungs are the potential sources of d ‐dimer in COVID‐19. 11 , 12 , 13 …”