Mediterranean alcohol-drinking pattern, low to moderate alcohol intake and risk of atrial fibrillation in the PREDIMED study

Highlights

• Effect of moderate alcohol consumption on atrial fibrillation risk is unclear.

• Moderate red wine consumption could be beneficial in a population at high cardiovascular risk.

• In a high CV risk population, moderate red wine intake was not associated with AF.

Abstract

Background and aims

There is ongoing controversy about the effect of a low to moderate alcohol consumption on atrial fibrillation (AF). Our aim is to assess the association between adherence to a Mediterranean alcohol drinking pattern and AF incidence.

Methods and results

A total 6527 out of the 7447 participants in the PREDIMED trial met our inclusion criteria. A validated frequency food questionnaire was used to measure alcohol consumption. Participants were classified as non-drinkers, Mediterranean alcohol drinking pattern (MADP) (10–30 g/d in men and 5–15 g/day in women, preferably red wine consumption with low spirits consumption), low-moderate drinking (<30 g/day men y and < 15 g/day women), and heavy drinking. We performed multivariable Cox regression models to estimate hazard ratios (HR) with 95% confidence intervals (95% CI) of incident AF according to alcohol drinking patterns. After a mean follow up of 4.4 years, 241 new incident AF cases were confirmed. Alcohol consumption was not associated to AF incidence among low-moderate drinkers (HR: 0.96; 95%CI: 0.67–1.37), adherents to MADP (HR: 1.15 95%CI: 0.75–1.75), or heavy drinkers (HR: 0.92; 95%CI: 0.53–1.58), compared with non-drinkers.

Conclusions

In a high cardiovascular risk adult population, a Mediterranean alcohol consumption pattern (low to moderate red wine consumption) was not associated with an increased incidence of AF.

Clinical trials

URL: http://www.controlled-trials.com. Unique identifier: ISRCTN35739639.

Introduction

Alcohol consumption is considered a risk factor for atrial fibrillation (AF). It is well known that excessive drinking, including binge drinking and a daily high amount of alcohol consumption, increases the risk of AF [1], [2], [3], [4], [5] as well as the recurrences of AF after an ablation [5]. Three meta-analyses have suggested a linear dose-response relation between the amount of alcohol habitually consumed and AF [6], [7], [8]. However, several studies and a recent meta-analysis have found that moderate-to-low consumption of alcohol does not show any association with the risk of AF [4], [5], [9], [10], [11]. Moreover, a curvilinear instead of a linear association has been suggested in a recent cohort study [10].

The type of alcoholic beverages and drinking pattern could also be important factors, but studies assessing these aspects in detail are scarce. A prospective study found that consumption of liquor or wine but not beer was significantly associated with AF risk [8]. More recently, a cohort study found relevant differences in the association between AF and a moderate to high consumption of specific beverage types [10]. However, the influence of these factors and other aspects such us the alcohol drinking pattern and the regular consumption of small amounts of alcohol, preferably of non-distilled alcoholic beverages have been less well studied.

It is well-recognized that low-to-moderate alcohol consumption has cardiovascular benefits, specially based on an inverse association with ischaemic heart disease. The American Heart Association recommends to limit alcoholic beverages to no more than 2 drinks per day for men and 1 drink per day for women, ideally consumed within meals [12], in those with a regular consumption. This pattern is associated with lower levels of blood pressure and inverse associations with incident cardiovascular disease and it is sometimes recommended in cardiovascular prevention (only for subjects who already consume alcohol and are older than 40 years and have a high cardiovascular risk) [13], [14]. However, there is currently a debate regarding the limits for a moderate alcohol drinking and if there is a difference between specific types of alcoholic beverages. It can be also questionable whether a healthy alcohol consumption pattern exists and if alcohol itself can provide cardioprotective benefits [15].

As far as we know, no previous study has specifically assessed the association between AF and the pattern of alcohol consumption which captures diverse aspects of the characteristics of alcohol intake, including the amount and type of alcohol consumed in the context of a Mediterranean population. The aim of our study was to describe the association between AF and several alcohol consumption patterns including the Mediterranean alcohol-drinking pattern (MADP) [13], [14]. Our hypothesis is that the cardioprotective effect of a healthy alcohol-drinking pattern could be offset in the case of AF due to its potential proarrhythmogenic effect.