D-dimer daily continuous tendency predicts the short-term prognosis for COVID-19 independently: A retrospective study from Northeast China

BACKGROUND AND OBJECTIVE: To study whether D-dimer daily continuous tendency could predict the short-term prognosis of COVID-19. PATIENTS AND METHODES: According to the short-term prognosis, 81 COVID-19 patients were divided into two groups, one of worse prognosis (Group W) and the other of better prognosis (Group B). The slope of D-dimer linear regression during hospitalization (SLOPE) was calculated as an indicator of D-dimer daily continuous tendency. The SLOPE difference between Group W and Group B was compared. The difference between the discharge results and the 3-month follow-up results was also compared. COX regression analysis was used to analyze the relationship between SLOPE and short-term prognosis of COVID-19. RESULTS: There were 16 patients in Group W and 65 patients in Group B. Group W had more critical proportion (p < 0.0001), indicating that the symptoms of its patients were more severe during hospitalization. ARDS, the most visible cause of worse prognosis, accounted for up to 68.75%, and many symptoms merged and resulted in worse prognosis. The D-dimer levels of Group W not only were significantly higher (p < 0.0001), but also showed an increasing trend. In addition, the D-dimer levels at discharge were significantly higher than those at follow-up (p = 0.0261), and the mean difference was as high as 0.7474. SLOPE significantly correlated with the short-term prognosis of COVID-19 independently (RR: 1.687, 95%CI: 1.345-2.116, P < 0.0001). The worst prognosis occurred most likely during the first month after COVID-19 diagnosis. CONCLUSION: Our study found that D-dimer daily continuous tendency independently correlates with worse prognosis and can be used as an independent predictor of the short-term prognosis for COVID-19.