DETERMINANTS OF THE ONSET OF MYOCARDIAL INFARCTION

本研究的目的是增加对以下方面的了解： 急性心肌梗死的发生，反过来， 更有效的预防性治疗 研究的动力 申请人最近的文件表明， 梗塞在早上6点到中午比在其他时间更频繁。 一天的时间。 这一事实引发了人们对广泛持有的- - 但缺乏支持--认为心肌梗死的发生 梗塞是随机事件。 马萨诸塞州的22个冠心病监护单位已经形成了一项研究 组，以调查心肌梗死时间的决定因素 采用病例对照设计。 超过3.5年 在此期间，有关事件的详细信息， 心肌梗死的发作将从 约7,000名患者。 相关风险 将通过比较 观察到的暴露频率紧接在心肌 梗死，预期值来自暴露频率 在同一患者中，在一天中的其他时间， 病人在同一时间。 以下假设将被测试：1） 心肌梗死（在一天中的任何时间），如假设 他直立的姿势，强烈的体力活动，一顿大餐， 严重的情绪压力，将被确定。 2)早高峰 发病时间越长， 针对群体的可变唤醒时间进行调整。 3)的 β受体阻滞剂可降低早晨发病的相对风险 和/或阿司匹林的使用。 4)晨起梗死的相对风险 不会因性别、年龄或吸烟而改变。 当梗死发作与觉醒时间的关系是 澄清，和可能的沉淀物评估，增加 关于触发过程的信息将是可用的。 等 信息将有助于设计预防性治疗， 然后可以在随机试验中进行评估。

The objective of this study is to gain increased knowledge about the onset of acute myocardial infarction which, in turn, will lead to more effective preventive therapy. The impetus for the study is the recent documentation by the applicants that the onset of infarction is more frequent from 6 a.m. to noon than during other times of the day. This fact calls into questions the widely held- -but poorly supported--impression that the onset of myocardial infarction is a random event. Twenty-two coronary care units in Massachusetts have formed a study group to investigate the determinants of the timing of myocardial infarction onset using a case-control design. Over a 3.5 year period, detailed information about the events immediately prior to the onset of myocardial infarction will be collected from approximately 7,000 patients. Relative risks associated with hypothesized risk factors for onset will be estimated by comparing observed exposure frequencies immediately prior to myocardial infarction with expected values derived from exposure frequencies in the same patients at other times of the day and in other patients at the same time of the day. The following hypotheses will be tested: 1) Precipitants of myocardial infarction (at any time of day) such as assumption of he upright posture, intense physical activity, a large meal, and acute emotional stress, will be identified. 2) The morning peak in infarct incidence will be higher and narrower when onset-time is adjusted for the variable wake-times of the population. 3) The relative risk of morning onset will e reduced by beta-blockade and/or aspirin usage. 4) The relative risk of morning infarction will not be altered by gender, age or cigarette smoking. When the relationship of infarction onset to time of awakening is clarified, and possible precipitants evaluated, increased information about triggering processes will be available. Such information will assist in the design of preventive therapy which can then be evaluated in randomized trials.