Abstract

Aims 

There is inconsistent evidence on the relation of alcohol intake with incident atrial fibrillation (AF), in particular at lower doses. We assessed the association between alcohol consumption, biomarkers, and incident AF across the spectrum of alcohol intake in European cohorts.

Methods and results 

In a community-based pooled cohort, we followed 107 845 individuals for the association between alcohol consumption, including types of alcohol and drinking patterns, and incident AF. We collected information on classical cardiovascular risk factors and incident heart failure (HF) and measured the biomarkers N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin I. The median age of individuals was 47.8 years, 48.3% were men. The median alcohol consumption was 3 g/day. N = 5854 individuals developed AF (median follow-up time: 13.9 years). In a sex- and cohort-stratified Cox regression analysis alcohol consumption was non-linearly and positively associated with incident AF. The hazard ratio for one drink (12 g) per day was 1.16, 95% CI 1.11–1.22, P < 0.001. Associations were similar across types of alcohol. In contrast, alcohol consumption at lower doses was associated with reduced risk of incident HF. The association between alcohol consumption and incident AF was neither fully explained by cardiac biomarker concentrations nor by the occurrence of HF.

Conclusions 

In contrast to other cardiovascular diseases such as HF, even modest habitual alcohol intake of 1.2 drinks/day was associated with an increased risk of AF, which needs to be considered in AF prevention.

Graphical Abstract

Hazard ratio for incident atrial fibrillation for alcohol consumption in gram per day by non-linear Cox regression plotted on the log-scale (N = 92 452). The model uses age as time scale and is sex and cohort stratified. The reference value is 0 g/day.

Introduction

Atrial fibrillation (AF) is an arrhythmia with a major impact on public health due to its increasing prevalence in ageing populations and its association with adverse outcomes, including stroke and heart failure (HF), with more than a doubling of mortality risk.1,2 The effect of alcohol on AF risk has remained ambiguous. For diseases predisposing to AF such as coronary artery disease3 or HF4,5 low to moderate alcohol consumption seems to be related to a lower incidence, while higher levels of consumption are associated with an increased risk.6 The reported associations with AF range from null associations at lower regular alcohol intake,5,7 rather linearly increasing in large meta-analyses8,9 to a more J-shaped relation in women.1 In particular, the association at low levels of alcohol consumption is less clear.

From a pathophysiological perspective, alcohol may exhibit direct effects on arrhythmogenesis as observed for the holiday heart syndrome.10–13 Acute alcohol consumption induces autonomic imbalance reflected by sinus tachycardia, predisposing to arrhythmia.10 Electrolyte disturbance and alterations of the acid-base balance are further pro-arrhythmic triggers. Chronic alcohol consumption is known to be correlated with changes in cardiac structure and function including cardiomyopathy.4,11–13

Habitual alcohol intake has been related to atrial remodelling as an intermediate AF phenotype in the community.12,13 At the same time, alcohol intake is also associated with the most prevalent risk factors of AF. Increased alcohol intake is accompanied by higher frequency of hypertension and obesity.14 In younger individuals with low-risk factor burden and heart disease, acute excessive alcohol consumption was not associated with higher AF burden.10 Furthermore, alcohol consumption is predictive of incident HF, which itself is a risk factor for new-onset AF4,6 and may help explain known associations.

Circulating cardiac biomarkers are quantitative measures which shed light on current cardiac pathophysiology. Troponin reflects myocardial injury, while N-terminal pro-B-type natriuretic peptide (NT-proBNP) indicates often chronic, subclinical wall stress.15 A recent study demonstrated that both biomarkers showed distinct patterns in relation to alcohol consumption.15 Whereas troponin concentrations decreased with higher alcohol consumption, NT-proBNP increased.15 Whether this pattern is related to AF risk remains to be shown.

A strong controversy remains for the relation of alcohol consumption with AF in individuals with low alcohol consumption. Therefore, we examined the association of alcohol consumption with incident AF while accounting for classical risk factors, HF and cardiac biomarkers across European cohorts.