What is the clinical evidence from this study?

Study design: RCT. Population: Non-valvular atrial fibrillation (n=7332). Intervention: Anticoagulation (ximelagatran or warfarin) in women vs. Anticoagulation in men. Primary outcome: All stroke (ischaemic/haemorrhagic) and systemic embolic event (p=0.016).

June 14, 2006Open Access

Anticoagulation in women with non-valvular atrial fibrillation in the stroke prevention using an oral thrombin inhibitor (SPORTIF) trials

Key Result

Women with atrial fibrillation receiving anticoagulation had a higher rate of stroke and systemic embolic events compared to men (2.08%/year vs 1.44%/year; P=0.016).

Study Design

Type

RCT (n=7,332)

Blinding

Open-label and double-blind

Structured PICO

Does the efficacy and safety of anticoagulation with ximelagatran versus warfarin differ between women and men with atrial fibrillation?

Population

7,332 patients with atrial fibrillation and one or more stroke risk factors (including 2,257 women) from the SPORTIF III and V trials

Intervention

Ximelagatran 36 mg twice daily

Comparator

Warfarin (target INR 2.0-3.0)

Outcome

All stroke (ischaemic/haemorrhagic) and systemic embolic eventhard clinical

In patients with atrial fibrillation, women are older, have more stroke risk factors, and experience higher rates of thromboembolism and anticoagulant-related bleeding compared to men.

Main Result

Absolute Event Rate: 2.08% vs 1.44%

p-value: p=0.016

Abstract

AIMS: The risk of stroke is greater among women with atrial fibrillation (AF) than men. Warfarin protects against stroke, but treatment-related bleeding occurs more often in women than in men. METHODS AND RESULTS: SPORTIF III (open label, n=3410) and V (double-blind, n=3922) included 2257 women with AF and one or more stroke risk factors randomized to warfarin target international normalized ratio (INR) 2.0-3.0 or ximelagatran (36 mg twice daily). Primary outcomes were all stroke (ischaemic/haemorrhagic) and systemic embolic event. Women were older, on average, than men, 73.4+/-8.0 vs. 69.8+/-9.0 years (P75-years old and women had more risk factors than men had (P<0.0001). The INR on warfarin (mean 2.5+/-0.7) was within target range for 67% of follow-up regardless of gender. Women more often developed primary events [2.08%/year, 95% confidence interval (CI) 1.60-2.56%/year vs. 1.44%/year, 95% CI 1.18-1.71%/year in men; P=0.016). Major bleeding rates were similar (P=0.766) but women experienced more overall (major/minor) bleeding (P<0.001). Warfarin was associated with more overall bleeding in both genders and more major bleeding in women than in men (P=0.001). CONCLUSION: When compared with men with AF, women in these studies were older and had more stroke risk factors. Women were more prone to anticoagulant-related bleeding; the higher rate of thrombo-embolism among women was related to more frequent interruption of anticoagulant therapy.