DeCarolis and colleagues1 are to be commended for their review of patients receiving an unadjusted dosage of enoxaparin sodium regardless of normal or moderate renal function and consequent bleeding episodes, demonstrating major bleeding in 5.7% of those with normal renal function compared with 22% of those with moderate renal function.
While the authors of this study and the corresponding Invited Commentary2 appropriately accentuate the need for revised recommendations that use lower doses or percentage dosage adjustments, there are certain features in this investigation that merit accentuation and additional explanation. First, the authors report that among those with active cancer, 18.1% of those with normal renal function and 13.6% of those with moderate renal function were transitioned to therapy with warfarin sodium. According to the CLOT (Randomized Comparison of Low-Molecular-Weight Heparin vs Oral Anticoagulant Therapy for the Prevention of Recurrent Venous Thromboembolism in Patients with Cancer) trial,3 dalteparin, a low-molecular-weight heparin, was more effective than warfarin in reducing the risk of recurrent thromboembolism without increasing bleeding risk. Activated factor X was measured in patients who developed clinically significant renal dysfunction. Therefore, it should be highlighted that patients with active cancer should not have been transitioned to warfarin therapy. In addition, as reports have demonstrated that dalteparin may have less bioaccumulation compared with enoxaparin, dalteparin may be a better option in patients with cancer with moderate renal impairment. Nevertheless, renal dosing recommendations for this low-molecular-weight heparin are also lacking.