Sarasin F P, Gaspoz J M, Bounameaux H
Department of Internal Medicine, Hôpital Cantonal, 24 rue Micheli du Crest, 1211 Geneva 14, Switzerland.
Arch Intern Med. 2000 Oct 9;160(18):2773-8. doi: 10.1001/archinte.160.18.2773.
Compared with aspirin alone, use of the new antiplatelet regimens, including aspirin combined with dipyridamole and clopidogrel bisulfate, has been found to further reduce the risk of stroke and other vascular events in patients who have experienced stroke or transient ischemic attack. However, their cost-effectiveness ratios relative to aspirin alone have not been estimated.
We developed a Markov model to measure the clinical benefits and the economic consequences of the following strategies to treat high-risk patients aged 65 years or older: (1) aspirin, 325 mg/d; (2) aspirin, 50 mg/d, and dipyridamole, 400 mg/d; and (3) clopidogrel bisulfate, 75 mg/d. Input data were obtained by literature review. Outcomes were expressed as US dollars per quality-adjusted life-year (QALY).
The use of aspirin combined with dipyridamole was more effective and less costly compared with the use of aspirin alone, providing a gain of 0.3 QALY for a 65-year-old patient. This regimen remained cost-effective despite wide sensitivity analyses. Clopidogrel was more effective and more costly compared with aspirin alone, yielding a gain of 0.2 QALY with a marginal cost-effectiveness ratio of $26,580 per each additional QALY (patient aged 65 years). Sensitivity analyses demonstrated that the efficacy of clopidogrel and its cost were key factors in determining its cost-effectiveness ratio compared with aspirin, which exceeded $50,000 when its efficacy decreased by half or its cost doubled.
To prevent stroke in high-risk patients, dipyridamole combined with aspirin was more effective and less costly than aspirin alone, and clopidogrel was cost-effective compared with current standards of medical practice, except in extreme scenarios.
与单独使用阿司匹林相比，新的抗血小板治疗方案，包括阿司匹林联合双嘧达莫以及硫酸氢氯吡格雷，已被发现可进一步降低经历过中风或短暂性脑缺血发作的患者发生中风及其他血管事件的风险。然而，相对于单独使用阿司匹林，它们的成本效益比尚未得到评估。
我们构建了一个马尔可夫模型，以衡量以下治疗65岁及以上高危患者策略的临床益处和经济后果：（1）阿司匹林，325毫克/天；（2）阿司匹林，50毫克/天，以及双嘧达莫，400毫克/天；（3）硫酸氢氯吡格雷，75毫克/天。输入数据通过文献综述获得。结果以每质量调整生命年（QALY）的美元数表示。
与单独使用阿司匹林相比，阿司匹林联合双嘧达莫的使用更有效且成本更低，为一名65岁患者带来了0.3个QALY的收益。尽管进行了广泛的敏感性分析，该方案仍具有成本效益。与单独使用阿司匹林相比，氯吡格雷更有效但成本更高，每增加一个QALY（65岁患者）可带来0.2个QALY的收益，边际成本效益比为26,580美元。敏感性分析表明，氯吡格雷的疗效及其成本是决定其与阿司匹林相比成本效益比的关键因素，当其疗效降低一半或成本翻倍时，成本效益比超过50,000美元。
为预防高危患者中风，双嘧达莫联合阿司匹林比单独使用阿司匹林更有效且成本更低，与当前医疗实践标准相比，氯吡格雷具有成本效益，极端情况除外。
