Efficacy and safety of direct oral anticoagulants and low molecular weight heparin for cancer-associated venous thromboembolism in patients with extremes in bodyweight

The purpose of this study is to describe the safety and efficacy of direct oral anticoagulants (DOACs) and low molecular weight heparin (LMWH) for the treatment of cancer-associated thrombosis in patients with extreme bodyweights. This was a single center, retrospective cohort study of adult patients on therapy for at least 6 months. The primary efficacy outcome of this study was to describe the time to first recurrent venous thromboembolism (VTE) within 6 months, compared between treatment and across weight cohorts. The primary safety objective was to describe the time to first major bleeding (MB) event within 6 months of starting therapy, between treatment types and among the weight groups. Secondary outcomes included incidence of recurrent VTE, MB, clinically relevant non-major bleeding (CRNMB) and the rate of VTE- or bleeding-related mortality. The time to recurrent VTE was comparable between all groups. In the BMI cohort, the time to first MB was 19.5 times longer for DOACs compared to LMWH in the overweight population (p = 0.007) and to first MB or CRNMB was 11.98 times longer (p = < 0.0001). In the weight cohort, the time to first MB or CRNMB was 14.63 times longer for DOACs compared to LMWH in the overweight population (p = 0.011) and 6.41 times longer in the normal weight population (p = 0.0009). There was an insufficient number of patients in the underweight group to perform statistical analysis. The results suggest that in overweight patients, DOACs have similar efficacy and fewer bleeding complications than LMWHs.