Long term, low intensity warfarin helps against deep vein thrombosis

Small doses of warfarin given long term can protect patients from recurrent deep vein thrombosis. A trial to discover whether low intensity warfarin was a useful preventive measure was stopped early after researchers decided that its efficacy was proved.

Because warfarin can cause unwanted and potentially dangerous bleeding, including stroke, doctors have been reluctant to give it indefinitely.

The new study, led by Paul Ridker of Brigham and Women's Hospital in Boston, Massachusetts, …