Abstract 3500: Low Molecular Weight Heparin versus Unfractionated Heparin for Anticoagulation of All Cause Atrial Fibrillation: A Comparative Cost Analysis from the NADROPAF Trial
Background: The few studies that compared low molecular weight heparin (LWMH) to unfractionated heparin (UH) for the anticoagulation of new onset atrial fibrillation (AF) did not address the issue of cost between the two strategies.
Methods: The NADROPAF trial (Nadroparin for Atrial Fibrillation) is a prospective randomized open label multicenter study comparing Nadroparin versus unfractionated heparin (UH) in pts with all cause AF of more than 48 hours duration. Pts > 75 year-old, with a history of < 6 months systemic embolism, cerebral or gastro-intestinal hemorrhage, prosthetic valve, left atrial thrombus or renal failure were excluded. Pts with valvular AF were not excluded. Pts were given LMWH or UH at a body weight adjusted dose until adequate anticoagulation with warfarin was obtained. From October 2001 to June 2005, 540 pts were included: 270 pts in the LMWH group and 270 in the UH group. The demographic characteristics including age, sex, and distribution of AF etiology were similar between the 2 groups. Treatment duration was of 5.9 ± 2.7 days in the LMWH group versus 6.0 ± 2.6 days in the UH group (p: NS). In hospital clinical events (death, hemorrhagic or ischemic events) and the total cost (medication, monitoring and hospital stay) were compared between the 2 groups.
Results: There was only one death that occurred in the UH group most likely no treatment related. There was no major stroke in either group. Transient ischemic attack was observed in 2 pts in the UH group. There was one major hemorrhagic event in each group. Minor hemorrhage was observed in 2 pts of the LMWH group and in one pt of the UH group. Overall the composite endpoint was 1.1% versus 1.8% in the LMWH group and the UH group respectively (p=0.65). The total in hospital cost for one patient was 259.9±24 US$ in the LMWH group and 198.5±20 US$ in the UH group (p<0.001).
Conclusions: Anticoagulation of atrial fibrillation from all cause including valvular heart disease can be safely and effectively accomplished by LMWH. However this latter strategy is significantly more expensive than the conventional strategy using unfractionated heparin.