While many epidemiologic studies have demonstrated an increase in the risk of AF for consumers of alcoholic beverages, there remains a question as to whether or not there is a threshold amount that would increase the risk. The present study concludes that “less than two alcohol units/day significantly increased the risk of incident AF, however, in men only. Reduction of even a moderate alcohol intake may thus reduce the risk of AF at the population level.”
While this may be the case, Forum members had a number of concerns about using the results of the present study to determine whether or not there is a threshold amount of alcohol necessary to increase the risk of AF. The methods used to judge alcohol consumption did not report the type of beverage or have a good estimate of the pattern of drinking, both of which factors are known to modify the health effects of alcohol. Further, the authors stated that there was evidence of considerable under-reporting of alcohol in their cohort, as the level of HDL noted in their “light” drinkers was above the level expected. This suggested to them that subjects in their lowest category of alcohol may actually have consumed more than they reported (probably about twice the reported amount of alcohol). This makes it difficult to determine if truly “light” drinking is associated with an increased risk of AF.
Overall, scientific data continue to show that light-to-moderate alcohol intake, especially when the pattern of drinking is found to be regular moderate consumption with food and without binge drinking, is associated with a lower risk of ischemic stroke and death. For the effects of alcohol intake on the risk of AF, the situation remains unclear. Unfortunately, the present study cannot answer the question as to whether there is, or is not, a clear threshold effect of alcohol intake on the risk of developing AF.
Reference: Ariansen I, Degerud E, Gjesdal K, Tell GS, Næss O. Examining the lower range of the association between alcohol intake and risk of incident hospitalization with atrial fibrillation. IJC Heart & Vasculature 2020;31:100679.