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

Abstract 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. Disclosures All Authors: No reported disclosures