One drink per day may be enough to increase risk for AF
As little as one alcoholic drink per day may confer elevated risk for development of atrial fibrillation, regardless of age and other CV risk factors, according to a study published in the European Heart Journal.
“Alcohol, even at very low regular consumption, appears to increase arrhythmia risk for AF, no clear threshold was observed,” Renate B. Schnabel, MD, MSc, interventional cardiologist and professor of cardiology at the University Heart and Vascular Center in Hamburg-Eppendorf, Germany, told Healio. “This is in contrast to other cardiovascular diseases, eg MI or HF. We could show the latter in our article too. At low doses, regular alcohol consumption was negatively associated with incident HF. When counseling patients on prevention of AF, these findings could be considered, and the risks and benefits of alcohol consumption should be weighed.”
For the community-based cohort study, researchers included 107,845 individuals from Sweden, Norway, Finland, Denmark and Italy (median age, 48 years; 48% men) to assess the association between alcohol consumption and incident AF. Information on CV risk factors and incident HF was also evaluated in addition to N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin I biomarkers.
According to the study, participants were slightly overweight (median BMI, 25.7 kg/m2) and had a mean alcohol intake of 8.7 g per day.
During a median follow-up time of 13.9 years, there were 5,854 cases of incident AF.
Researchers observed a positive association between alcohol consumption and incident AF, with elevated risk evident at as little as one drink, or 12 g of alcohol, per day (HR = 1.16; 95% CI, 1.11-1.22; P < .001). Further adjustment for CV risk factors did not impact the association significantly (HR = 1.18; 95% CI, 1.12-1.25; P < .001).
According to the study, the cutoff for statistical significance was consumption of 2 g of alcohol per day and the association pattern was similar across various types of alcohol consumed.
Researchers did not observe any association between alcohol consumption and incident AF by sex (P for interaction = .07).
The risk for AF at one drink per day did not change significantly after the exclusion of participants older than 80 years (HR = 1.17; 95% CI 1.11-1.22; P < .001).
“Our study is observational and therefore cannot prove causality because so many factors are related to alcohol intake (general nutrition/diet, comorbidities, social environment, social expectancy in reporting alcohol consumption in a study environment),” Schnabel told Healio. “However, it will be difficult/not possible to perform a blinded, randomized study on alcohol consumption. Therefore, we must find other evidence for the observed findings. In particular, the mechanisms of alcohol intake on the arrhythmia need to be identified.”
Alcohol with AF and risk for HF
In an analysis of 69,084 participants for whom AF and HF data were available, the researchers found a J-shaped relationship between alcohol consumption and risk for HF (P < .001), with the lowest HR at 20 g, or 1.6 drinks, per day.
According to the study, the association between incident HF as a time-dependent covariate and alcohol consumption with incident AF as an outcome was not statistically significant (P for interaction = .07).
Researchers noted weak associations between NT-proBNP (r = –0.1) and high-sensitivity troponin I (r = 0.12) and alcohol intake; however, biomarker concentrations did not significantly modify the effect of alcohol consumption on incident AF.
Lowering intake for prevention, management of AF
“A significant relationship between alcohol and AF was identified, and even small quantities of alcohol were associated with an increased, albeit small, risk of incident AF,” Jorge Wong, MD, MPH, cardiologist and cardiac electrophysiologist at Hamilton Health Sciences in Ontario, Canada, and David Conen, MD, MPH, associate professor of medicine at McMaster University in Hamilton, Ontario, Canada, wrote in a related editorial. “Together with a recent randomized trial showing that a reduction in alcohol intake led to a reduction in AF recurrence, these data suggest that lowering alcohol consumption may be important for both prevention and management of AF. Importantly, any reduction in low to moderate alcohol consumption to potentially prevent AF needs to be balanced with the potentially beneficial association low amounts alcohol may have with respect to other cardiovascular outcomes.
“The net clinical benefit of consuming low amounts of alcohol requires further study, ideally in adequately powered randomized trials,” Wong and Conen wrote. “Until then, each individual has to make its own best educated decision as to whether consuming up to one alcoholic drink per day is worthwhile and safe.”
For more information:
Renate B. Schnabel, MD, MSc, can be reached at firstname.lastname@example.org.