75 - Systemic Anticoagulation Use Is Independently Associated with Lower Mortality in Hospitalized COVID-19 Patients with D-dimer Level Higher Than 5 Mcg/ml

Background: Elevated D-dimer level is frequently seen in patients with COVID-19 and is associated with worse clinical outcomes. The potential benefit of systemic anticoagulation in COVID-19 has been suggested, but data lack on when to initiate anticoagulation. We aimed to identify a cut-off value of D-dimer at which anticoagulation may provide mortality benefit in COVID-19.

Methods: A retrospective review was conducted for a cohort of patients hospitalized with COVID-19 at a 262-bed community hospital in a Washington D.C. suburb. Patients hospitalized between April 1, 2020, and April 30, 2020, with laboratory-confirmed COVID-19 were included if d-dimer levels were checked during hospitalization. Demographics, laboratory results, and hospital courses were reviewed. Logistic regression was used to examine the association between anticoagulation and in-hospital mortality, controlling for the d-dimer value. The association was examined in subgroups with different d-dimer cut-offs. Multivariable logistic regression models were developed to assess if the association between anticoagulation and mortality remains after adjusting for other mortality risk factors.

Results: 101 patients were included in the study and 32 (31.7%) died during hospitalization. The average age was 61.2 ± 14.8 years old and 50.5% were males. Older age, male sex, hypertension, and peak d-dimer level were associated with mortality in univariable analysis (p< 0.05). For patients with peak d-dimer level >3mcg/mL, anticoagulation use was associated with lower mortality after controlling for the d-dimer level (OR 0.25, 95% CI 0.06-0.97 p=0.045). This association weakened after adjusting for age, sex, and hypertension. (OR 0.33, 95% CI 0.07-1.46, p=0.143). For patients with peak d-dimer level >5 mcg/mL, anticoagulation use was associated with lower mortality after controlling for the d-dimer level (OR 0.11, 95% CI 0.02-0.68, p=0.017) and this association remained significant after adjusting for age, sex, and hypertension (OR 0.11, 95% CI 0.01-0.86, p=0.035).

Conclusion: In hospitalized COVID-19 patients with a d-dimer level higher than 5 mcg/mL, anticoagulation use was independently associated with lower mortality.