ALCOHOL AND CORONARY HEART DISEASE 725 Does heavy alcohol consumption increase CHD risk ?

Medical and political discussions of the health effects of alcohol should give prominence to the individual and social damage caused by alcohol.1 In the interests of public health, it is right that any discussion should begin and end with these problems. In the middle, however, perhaps a small place may be reserved for continued exploration of why moderate drinkers appear to have a lower mortality risk, and particularly a lower incidence of coronary heart disease (CHD), than abstainers. Is the association causal? That is, do moderate amounts of alcohol exert a protective effect? As suggested recently, non-drinkers may include a number of ex-drinkers who gave up because of ill-health.2 Hence a high mortality would not be surprising. This is plausible, but other evidence suggests different reasons for the CHD advantage of moderate drinkers. I should like to consider the evidence on two questions: does heavy alcohol consumption increase the risk of CHD and does moderate consumption protect against it? A major problem concerns the varying definitions of ‘heavy’ and ‘moderate’. There is agreement that daily consumption of more than 80 g of ethanol is ‘heavy’.3 This is the amount of alcohol contained in five pints of beer, or a bottle of table wine, or one third of a bottle of spirits (Table 1). However, others would put the dividing line between moderate and heavy at a lower level than this.4 Presumably an appropriate way to define ‘heavy’ is the level above which alcohol-associated problems emerge; but this is a complex subject since alcohol is associated with a wide range of medical and social problems. The question considered here relates only to coronary heart disease. It is accepted that heavy alcohol consumption can have a direct toxic effect on the myocardium,5 resulting in alcoholic cardiomyopathy. This will not be considered further here. © International Epidemiological Association 1984 Printed in Great Britain

关于酒精对健康影响的医学和政治讨论应突出酒精造成的个人和社会损害。1为了公共健康，任何讨论都应以这些问题为出发点和落脚点，这是正确的。然而，在讨论过程中，或许可以留出一小部分空间，继续探究为什么适量饮酒者似乎比戒酒者死亡率更低，尤其是患冠心病（CHD）的几率更低。这种关联是因果关系吗？也就是说，适量的酒精是否具有保护作用？正如最近所提出的，不饮酒者可能包括一些因健康不佳而戒酒的人。2因此，较高的死亡率也就不足为奇了。这似乎合理，但其他证据表明适量饮酒者在冠心病方面具有优势的原因有所不同。我想就两个问题考虑相关证据：大量饮酒会增加患冠心病的风险吗？适量饮酒能预防冠心病吗？一个主要问题涉及“大量”和“适量”的不同定义。人们一致认为，每天摄入超过80克乙醇即为“大量”饮酒。3这相当于五品脱啤酒、一瓶餐酒或三分之一瓶烈酒所含的酒精量（表1）。然而，其他人会将适量和大量的分界线设定在比这更低的水平。4大概定义“大量”的一个合适方法是，超过这个水平就会出现与酒精相关的问题；但这是一个复杂的问题，因为酒精与多种医学和社会问题相关。这里所考虑的问题仅与冠心病有关。人们公认大量饮酒会对心肌产生直接的毒性作用，5导致酒精性心肌病。这里不再进一步讨论这个问题。©国际流行病学协会1984年 英国印刷