Response to Letter Regarding Article, “To Drink or Not to Drink? That Is the Question”
We thank Dr Stranges and associates for their interest in our article.1 We agree that there are limitations in many articles in the literature on the subject of alcohol and heart disease, and we did describe some of these in our article, including our statement that, “When we reviewed the literature, it became very evident that definitions describing how much alcohol is in a drink may vary remarkably by article and country, and terms such as light, moderate, and heavy drinking are variably defined” (p 1306). We also stated, “Few studies were conducted to test whether a sex difference is associated with drinking alcohol and the incidence of coronary artery disease” (p 1309).
Other limitations of published studies were also listed in our article, including “unreliable self-reporting of alcohol use, failure to always take into account the effects of alcohol on non-cardiovascular morbidity and mortality, lack of cost/benefit analysis, changes in alcohol use over time (ie, some patients who may initially drink a supposed safe dose of alcohol [≤one drink per day] from a cardiovascular viewpoint may increase their dose over time), failure to take into account lifelong risk, and differences in ethnicity or culture”(p 1313).
Although it is true that not all studies took into account drinking patterns, some did, and we raised the issue of drinking patterns in our article. “Neither the type of drink nor its relations to meals had significant impact of reducing the risk of nonfatal infarction or total coronary heart disease. Of note, although in general, studies in Europe have often shown a cardiovascular advantage of wine, most studies in the United States have not shown much difference according to the type of alcohol. Perhaps this finding is related to the confounding variable of differences in patterns of drinking. In the United States it is more common for little or no drinking to occur during the week, with heavy drinking on the weekend” (p 1310).
Monthly, weekly, and daily alcohol consumption were compared in 1 study. “Binge drinking was associated with higher blood pressure than regular constant drinking” (p 1312). Other aspects regarding binge drinking were also discussed on that page.
Therefore, we certainly agree with Dr Stranges et al that there are methodological limitations to these studies and that the pattern of drinking is important. Most clinicians are well aware of the dangers of binge drinking. The literature in this field is vast, and although we would like to have included more references and studies on these important topics, we were already at the length limit for that article.
Regarding our suggestions for a randomized trial, the pattern of drinking in such a trial would obviously need to exclude binge drinking, and we specifically suggested that the treated group receive either 1 or a half drink per day. We do not think that waiting for additional epidemiological research to be performed is necessary before clinical trials are undertaken. In fact, given the limitations of the various epidemiological studies pointed out by both Stranges et al and us, only a large, prospective, randomized trial will definitely answer the question of whether moderate alcohol intake can ever be considered as a preventative therapy for cardiovascular disease.