Predictive value of D-dimer in the clinical outcome of severe COVID19 patients: Are we giving it too much credit?

Background COVID-19 is a new form of acute respiratory failure leading to multiorgan failure and ICU admission. Gathered evidence suggests that a 3-fold rise in D-dimer concentrations may be linked to poor prognosis and higher mortality. Purpose To describe D-dimer admission profile in severe ICU COVID19 patients and its predictive role in outcomes and mortality. Methods Single-center retrospective cohort study. All adult patients admitted to ICU with COVID19 were divided into 3 groups: (1) Lower-values group (D-dimer levels < 3-fold normal range value [NRV] [500ng/mL]), Intermediate-values group (D-dimer >= 3-fold and <10-fold NRV) and Higher-value group (>= 10-fold NRV). Results 118 patients (mean age 63 years, 73% males) were included (N = 73 Lower-values group, N = 31 Intermediate-values group; N = 11 Higher-values group). Mortality was not different between groups (p = 0.51). Kaplan-Meier survival curves revealed no differences (p = 0.52) between groups, nor it was verified even when gender, age, ICU length of stay, and SOFA score were considered as covariables. Conclusions In severe COVID19 patients, the D-dimer profile does not retain a predictive value regarding patients' survivability and should not be used as a surrogate of disease severity.