Antiphospholipid antibodies and vitamin D deficiency in COVID-19 infection with and without venous or arterial thrombosis: A pilot case-control study.

BACKGROUND: Coronavirus disease-2019 (COVID-19) is associated with thromboembolism. Antiphospholipid antibody (APLa) formation is one of the mechanisms. Vitamin D deficiency has been associated with thrombosis in antiphospholipid antibody syndrome. OBJECTIVE: Measure APLa and vitamin D in hospitalized COVID-19 patients with and without thrombosis to evaluate if thromboembolism is associated with concomitant APLa and vitamin D deficiency. METHODS: Case-control study. Hospitalized COVID-19 patients with a thromboembolic event (ischemic stroke, myocardial infarction, deep venous thrombosis/pulmonary embolism, Cases n = 20). Controls (n = 20): Age, sex-matched without thromboembolic events. Patients with autoimmune disorders, antiphospholipid antibody syndrome, thrombophilia, anticoagulation therapy, prior thromboembolism, chronic kidney disease 3b, 4, end-stage renal disease, and malignancy were excluded. Given the limited current literature on the role of concomitant antiphospholipid antibodies and vitamin D deficiency in causing venous and/or arterial thrombosis in hospitalized COVID-19 patients, we enrolled 20 patients in each arm. Anti-cardiolipin IgG/IgM, beta-2 glycoprotein-1 IgG/IgM, lupus anticoagulant and vitamin D levels were measured in both groups. RESULTS: Cases were 5.7 times more likely to be vitamin D deficient (OR:5.7, 95% CI:1.3-25.6) and 7.4 times more likely to have any one APLa (OR:7.4, 95% CI: 1.6-49.5) while accounting for the effects of sex. Patients with both APLa and vitamin D deficiency had significantly more thrombosis compared to patients who were antibody positive without vitamin D deficiency (100% vs 47.4%; p = 0.01). CONCLUSIONS: Thrombosis in COVID-19 was associated with concomitant APLa and vitamin D deficiency. Future studies in COVID-19 should assess the role of vitamin D in reducing thrombosis.

Anticoagulation Management and Outcomes in Patients With Covid-19 With Propensity Score Matching: A Multicenter Retrospective Cohort Study.

BACKGROUND: Therapeutic doses of anticoagulation have been administered to patients with coronavirus-19 disease (Covid-19) without thromboembolism, although there is a lack of robust evidence supporting this practice. STUDY QUESTION: To compare outcomes between patients admitted to the hospital for Covid-19 who received full-dose anticoagulation purely for the indication of Covid-19 and patients who received prophylactic doses of anticoagulation. STUDY DESIGN: This is a multicenter retrospective cohort study, including 7 community hospitals in Michigan. Patients were >18 years of age, confirmed positive for Covid-19 by polymerase chain reaction, and admitted to the hospital between March 10 and May 3, 2020. Exposed group: Patients receiving therapeutic dose anticoagulation for Covid-19 for any duration excluding clinically evident venous thromboembolism, atrial fibrillation, and myocardial infarction; control group: Patients receiving prophylactic anticoagulation. Propensity score matching was used to adjust for the nonrandomized nature of the study. MEASURES AND OUTCOMES: The primary endpoint: 30-day in-hospital mortality. Secondary endpoints: intubation, length of hospital stay, and readmissions in survivors. RESULTS: A total of 115 exposed and 115 control patients were analyzed. Rates of 30-day in-hospital mortality were similar (exposed: 33.0% vs. control: 28.7%). Controlling for institution, there was no significant association between treatment and 30-day in-hospital mortality (hazard ratio: 0.63; 95% confidence interval: 0.37-1.06). Survivors had statistically similar length of hospital stay and readmission rates. CONCLUSIONS: We found no difference in mortality in patients with Covid-19 without clinically evident venous thromboembolism, atrial fibrillation, and myocardial infarction who received therapeutic versus prophylactic doses of anticoagulation.