The effect and safety of the antithrombotic therapies in patients with atrial fibrillation and CHADS score 1.
BACKGROUND
The revised ACC/AHA/ESC 2006 guideline recommends either aspirin or warfarin for the prevention of ischemic stroke in patients with atrial fibrillation (AF) in CHADS(2) score 1. We hypothesized that warfarin is superior to aspirin therapy for the prevention of stroke without increasing bleeding complication in AF patients with CHADS(2) score 1.


RESULTS
Among 1,502 patients (mean 62.4 +/- 13.8 years old, male 65.4%) who were treated for nonvalvular AF without previous stroke, the number of patients with CHADS(2) score 1 was 422 (62.9 +/- 10.7 years old, male 290 [68.7%]) and their antithrombotic therapies were as follows: warfarin (n = 143), aspirin (n = 124), other antiplatelet (n = 45), and no antithrombosis (none: n = 110). We reviewed the incidences of ischemic stroke, mortality, and bleeding complications during the follow-up period. Results were: (1) during 22.3 +/- 17.8 months of follow-up, the incidence of ischemic stroke was significantly lower in warfarin (6 patients, 4.2%, mean international normalized ratio [INR] 2.0 +/- 0.5 IU) than in aspirin (16 patients, 12.9%, P = 0.008) than none (23 patients, 20.9%, P < 0.001) without differences in all-cause mortality. (2) The incidence of major bleeding (decrease in hemoglobin >or=2 g/dL, requiring hospitalization or red blood cell transfusion >or=2 pints) was not different between warfarin (2.1%) and aspirin (0.8%, P = NS), but minor bleeding was more common in warfarin (10.5%) than in aspirin (2.4%, P = 0.007).


CONCLUSIONS
In AF patients with CHADS(2) score 1, warfarin was better to prevent ischemic stroke than aspirin without increasing the incidence of major bleeding complications. However, the incidence of minor bleeding was higher in the warfarin group than the aspirin group.
Lee
Byung Ho
BH
Yonsei University Health System, Seoul, Republic of Korea.
Park
Jae Seok
JS
Park
Jae Hyung
JH
Park
Jong Seung
JS
Kwak
Jae Jin
JJ
Hwang
Eui Seock
ES
Kim
Sook Kyoung
SK
Choi
Dong Hoon
DH
Kim
Young-Hoon
YH
Pak
Hui-Nam
HN
D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects / Q000627:therapeutic use; D001241:Aspirin / Q000009:adverse effects / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology; D002545:Brain Ischemia / Q000150:complications / Q000453:epidemiology / Q000473:pathology; D005260:Female; D005343:Fibrinolytic Agents / Q000009:adverse effects* / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006470:Hemorrhage / Q000139:chemically induced / Q000453:epidemiology; D006801:Humans; D019934:International Normalized Ratio; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects / Q000627:therapeutic use; D016016:Proportional Hazards Models; D012044:Regression Analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D020521:Stroke / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D014859:Warfarin / Q000009:adverse effects / Q000627:therapeutic use
D000925:Anticoagulants; D005343:Fibrinolytic Agents; D010975:Platelet Aggregation Inhibitors; D014859:Warfarin; D001241:Aspirin