Detre K, Peduzzi P
Control Clin Trials. 1982 Dec;3(4):355-64. doi: 10.1016/0197-2456(82)90025-3.
In the VA Coronary Artery Surgery Study 84 of the 354 patients randomized to medical treatment had subsequent bypass surgery during a 6-year follow-up period. Of these, 18 had left main disease. The remaining 66 of 311 without left main disease crossed over to surgery at a constant rate of about 4% per year. The traditional assumption that patients who crossed over were at greater risk of dying than those who adhered was not substantiated by an analysis of known baseline risk factors. Crossover was not related to number of vessels diseased or other angiographic or noninvasive risk factors but was related to severity of angina which was not a risk factor in this study. These findings lend support to the validity of analyzing our survival data by the crossover method where nonadherers are counted as lost to follow-up at the time of treatment change.
在退伍军人事务部冠状动脉手术研究中，354名随机接受药物治疗的患者中有84人在6年随访期内接受了后续搭桥手术。其中，18人患有左主干疾病。在311名无左主干疾病的患者中，其余66人以每年约4%的恒定速率转而接受手术治疗。对已知基线风险因素的分析并未证实传统观点，即转而接受手术治疗的患者比坚持药物治疗的患者死亡风险更高。转而接受手术治疗与病变血管数量或其他血管造影或非侵入性风险因素无关，但与心绞痛严重程度有关，而心绞痛严重程度在本研究中并非风险因素。这些发现支持了通过交叉方法分析我们的生存数据的有效性，在这种方法中，不坚持治疗的患者在治疗改变时被视为失访。
