Factors related to viral clearance time in patients with critical COVID‑19

To evaluate the related factors to virus clearance time in patients with critical COVID-19. A total of 63 patients with critical COVID-19 who had viral clearance were enrolled from Feb 1 to Mar 20, 2020, in Renmin Hospital of Wuhan University. Univariate analyses were used to compare the related factors between groups with different viral clearance time(≤30 days viral clearance group versus >30 days viral clearance group). COX regression analysis was also used to evaluate the factors related to virus clearance time. A total of 63 critical patients with COVID-19 who had viral clearance were collected, including 35 male and 28 female. The mean age was(63. 65±14. 06) years, range from 29 to 89 years. The median viral clearance time was 27 days(IQR, 21～36 days). In univariate analysis, the following factors had significant differences between ≤30 days viral clearance group and >30 days viral clearance group(all P<0. 05) as: age>70 years old, COPD, WBC>9. 5×109/L, LYM<0. 6×109/L, CRP>50 mg/L, D-dimer>5 mg/L,CK>200 U/L, LDH>300 U/L, CD4+T-cell<250 cells/μL, CD8+T-cell<150 cells/μL, corticosteroid treatment and high flow oxygen therapy. Multivariate analysis confirmed that age>70 years old(HR: 0. 207, 95% CI: 0. 090-0. 479), LYM<0. 6×109/L(HR: 0. 276, 95%CI: 0. 116-0. 656),D-dimer>5 mg/L(HR: 0. 243, 95% CI: 0. 105-0. 563), and ALT>50 U/L(HR: 0. 483, 95%CI:0. 239-0. 973) were inconducive to the elimination of the virus. Critical COVID-19 patients have longer hospital stays and significantly different virus clearance time. There are many factors that affect viral clearance time. As adverse factors, age>70 years old, LYM<0. 6×109/L,D-dimer >5 mg/L and ALT>50 U/L may prolong the viral clearance time. Early detection of related factors and timely treatment are beneficial to shorten the time of viral clearance and improve the prognosis of the disease.