Elevated D-Dimer Levels are Associated with Increased Risk of Mortality in COVID-19: A Systematic Review and Meta-Analysis

Abstract

AbstractIntroductionThe 2019 novel Coronavirus (2019-nCoV), now declared a pandemic has an overall case fatality of 2–3% but it is as high as 50% in critically ill patients. D-dimer is an important prognostic tool, often elevated in patients with severe COVID-19 infection and in those who suffered death. In this systematic review, we aimed to investigate the prognostic role of D-dimer in COVID-19 infected patients.MethodsWe searched PubMed, Medline, Embase, Ovid, and Cochrane for studies reporting admission D-dimer levels in COVID-19 patients and its effect on mortality.Results18 studies (16 retrospective and 2 prospective) with a total of 3,682 patients met the inclusion criteria. The pooled mean difference (MD) suggested significantly elevated D-dimer levels in patients who died versus those survived (MD 6.13 mg/L, 95% CI 4.16 − 8.11, p <0.001). Similarly, the pooled mean D-dimer levels were significantly elevated in patients with severe COVID-19 infection (MD 0.54 mg/L, 95% CI 0.28 − 0.8, p< 0.001). In addition, the risk of mortality was four-fold higher in patients with positive D-dimer vs negative D-dimer (RR 4.11, 95% CI 2.48 − 6.84, p< 0.001) and the risk of developing the severe disease was two-fold higher in patients with positive D-dimer levels vs negative D-dimer (RR 2.04, 95% CI 1.34 − 3.11, p < 0.001).ConclusionOur meta-analysis demonstrates that patients with COVID-19 presenting with elevated D-dimer levels have an increased risk of severe disease and mortality.