Equal effectiveness of very-low-intensity anticoagulation and standard low-intensity anticoagulation: a pilot study.
We compared the efficacy of very-low-intensity oral anticoagulation (OA) with that of the recommended standard low-intensity oral anticoagulation, using international normalized ratios (INRs). We enrolled 101 patients into a pilot study--51 patients in the very-low-intensity anticoagulation arm (INR 1.4 to 2.0) and 50 in the standard low-intensity anticoagulation arm (INR 2.0 to 3.0). They were monitored for thrombotic/embolic and hemorrhagic complications for an average follow-up of 1.5 years. Two thrombotic/embolic events occurred in the very-low-intensity group; no thrombotic/embolic events occurred in the standard low-intensity group. No major bleeding occurred in the very-low-intensity group; one major hemorrhagic event occurred in the standard low-intensity group. These findings did not achieve a statistically significant difference in major complications between the two groups. It appears that very-low-intensity OA (INR 1.4 to 2.0) is as effective in preventing thromboses as standard low-intensity OA (INR 2.0 to 3.0).
D000284:Administration, Oral; D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000517:prevention & control; D002561:Cerebrovascular Disorders / Q000517:prevention & control; D016903:Drug Monitoring; D004617:Embolism / Q000517:prevention & control; D005260:Female; D005500:Follow-Up Studies; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D002546:Ischemic Attack, Transient / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D010865:Pilot Projects; D011655:Pulmonary Embolism / Q000517:prevention & control; D012008:Recurrence; D013924:Thrombophlebitis / Q000517:prevention & control; D013927:Thrombosis / Q000517:prevention & control; D014859:Warfarin / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
D000925:Anticoagulants; D014859:Warfarin