Safety of intermediate dose of low molecular weight heparin in COVID-19 patients

Coagulopathy represents one of the most important determinants of morbidity and mortality in coronavirus disease-19 (COVID-19). Whether standard thromboprophylaxis is sufficient or higher doses are needed, especially in severe patients, is unknown. To evaluate the safety of intermediate dose regimens of low-weight molecular heparin (LWMH) in COVID-19 patients with pneumonia, particularly in older patients. We retrospectively evaluated 105 hospitalized patients (61 M, 44 F; mean age 73.7 years) treated with subcutaneous enoxaparin: 80 mg/day in normal weight and mild-to-moderate impair or normal renal function; 40 mg/day in severe chronic renal failure or low bodyweight (< 45 kg); 100 mg/day if bodyweight was higher than 100 kg. All the patients had radiologically confirmed pneumonia and 63.8% had severe COVID-19. None of the patients had fatal haemorrhage; two (1.9%) patients had a major bleeding event (one spontaneous hematoma and one gastrointestinal bleeding). Only 6.7% of patients needed transfusions of red blood cells. One thrombotic event (pulmonary embolism) was observed. When compared to younger patients, patients older than 85 years had a higher mortality (40% vs 13.3%), but not an increased risk of bleeding or need for blood transfusion. The use of an intermediate dose of LWMH appears to be feasible and data suggest safety in COVID-19 patients, although further studies are needed.