Go Alan S, Hylek Elaine M, Chang Yuchiao, Phillips Kathleen A, Henault Lori E, Capra Angela M, Jensvold Nancy G, Selby Joe V, Singer Daniel E
Division of Research, Kaiser Permanente of Northern California, Oakland, CA 94612, USA.
JAMA. 2003 Nov 26;290(20):2685-92. doi: 10.1001/jama.290.20.2685.
Warfarin has been shown to be highly efficacious for preventing thromboembolism in atrial fibrillation in randomized trials, but its effectiveness and safety in clinical practice is less clear.
To evaluate the effect of warfarin on risk of thromboembolism, hemorrhage, and death in atrial fibrillation within a usual care setting.
Cohort study assembled between July 1, 1996, and December 31, 1997, and followed up through August 31, 1999.
Large integrated health care system in Northern California.
Of 13,559 adults with nonvalvular atrial fibrillation, 11,526 were studied, 43% of whom were women, mean age 71 years, with no known contraindications to anticoagulation at baseline.
Ischemic stroke, peripheral embolism, hemorrhage, and death according to warfarin use and comorbidity status, as determined by automated databases, review of medical records, and state mortality files.
Among 11,526 patients, 397 incident thromboembolic events (372 ischemic strokes, 25 peripheral embolism) occurred during 25,341 person-years of follow-up, and warfarin therapy was associated with a 51% (95% confidence interval [CI], 39%-60%) lower risk of thromboembolism compared with no warfarin therapy (either no antithrombotic therapy or aspirin) after adjusting for potential confounders and likelihood of receiving warfarin. Warfarin was effective in reducing thromboembolic risk in the presence or absence of risk factors for stroke. A nested case-control analysis estimated a 64% reduction in odds of thromboembolism with warfarin compared with no antithrombotic therapy. Warfarin was also associated with a reduced risk of all-cause mortality (adjusted hazard ratio, 0.69; 95% CI, 0.61-0.77). Intracranial hemorrhage was uncommon, but the rate was moderately higher among those taking vs those not taking warfarin (0.46 vs 0.23 per 100 person-years, respectively; P =.003, adjusted hazard ratio, 1.97; 95% CI, 1.24-3.13). However, warfarin therapy was not associated with an increased adjusted risk of nonintracranial major hemorrhage. The effects of warfarin were similar when patients with contraindications at baseline were analyzed separately or combined with those without contraindications (total cohort of 13,559).
Warfarin is very effective for preventing ischemic stroke in patients with atrial fibrillation in clinical practice while the absolute increase in the risk of intracranial hemorrhage is small. Results of randomized trials of anticoagulation translate well into clinical care for patients with atrial fibrillation.
在随机试验中，华法林已被证明在预防心房颤动血栓栓塞方面具有高度有效性，但在临床实践中其有效性和安全性尚不清楚。
评估在常规护理环境下华法林对心房颤动患者血栓栓塞、出血和死亡风险的影响。
队列研究，于1996年7月1日至1997年12月31日期间组建，并随访至1999年8月31日。
北加利福尼亚州的大型综合医疗保健系统。
在13559例非瓣膜性心房颤动成人中，对11526例进行了研究，其中43%为女性，平均年龄71岁，基线时无已知抗凝禁忌证。
根据华法林使用情况和合并症状态，通过自动数据库、病历审查和州死亡档案确定缺血性卒中、外周栓塞、出血和死亡情况。
在11526例患者中，在25341人年的随访期间发生了397例血栓栓塞事件（372例缺血性卒中，25例外周栓塞），在调整潜在混杂因素和接受华法林的可能性后，与未使用华法林治疗（未进行抗栓治疗或使用阿司匹林）相比，华法林治疗使血栓栓塞风险降低了51%（95%置信区间[CI]，39%-60%）。无论有无卒中危险因素，华法林在降低血栓栓塞风险方面均有效。一项巢式病例对照分析估计，与未进行抗栓治疗相比，华法林使血栓栓塞的比值比降低了64%。华法林还与全因死亡率降低相关（调整后的风险比，0.69；95%CI，0.61-0.77）。颅内出血不常见，但服用华法林者的发生率略高于未服用者（分别为每100人年0.46例和0.23例；P=0.003，调整后的风险比，1.97；95%CI，1.24-3.13）。然而，华法林治疗与非颅内大出血的调整后风险增加无关。当分别分析或合并分析基线时有禁忌证的患者与无禁忌证的患者（共13559例）时，华法林的效果相似。
在临床实践中，华法林对预防心房颤动患者的缺血性卒中非常有效，而颅内出血风险的绝对增加很小。抗凝随机试验的结果很好地转化为心房颤动患者的临床护理。
