Retrospective Study of Thrombosis in Hospitalized Patients with COVID-19 in Rural North Carolina

Some patients with COVID-19 develop life-threatening thrombotic complications including myocardial infarction, deep vein thrombosis, pulmonary embolism, disseminated intravascular coagulation, and ischemic stroke. These inflammatory and hypercoagulable states have been well documented in patient cohorts from metropolitan areas, but not in more rural populations, nor has a data-driven treatment plan been developed for thrombotic COVID-19 patients.

We undertook a retrospective case-control study of COVID-19-positive patients to analyze the impact of thrombosis on various clinical endpoints including terminal diagnosis and disease severity. Prevalence and impact of thrombosis were determined using medical records from 2237 COVID-19-positive patients hospitalized in Cumberland County, North Carolina. Odds ratios for terminal diagnosis, death, ICU admission, and ventilation were calculated based on thrombosis status, D-dimer level, or type of antithrombotic treatment.

Terminal diagnosis [OR 1.81; 95% CI (1.10, 2.98)], ICU admission [2.25; (1.33, 3.81)], and ventilation [2.46; (1.45, 4.18)] were all more likely in thrombotic patients (N = 97) compared to nonthrombotic patients (N = 2140) after adjusting for age. D-dimer levels were associated with death overall, but not among thrombotic patients. Treatments that combined antiplatelet and anticoagulant drugs appeared to be more efficacious than anticoagulants alone in preventing death and severe disease.

Patient medical history prior to hospitalization was not evaluated.

In this cohort, those with thrombosis are at increased risk for adverse outcomes including death and severe disease. Antithrombotic therapy that includes antiplatelet drugs provides improved outcomes. Higher-powered prospective trials will be necessary to confirm any potential merits of antiplatelet therapy.